sii: personal feedback · web viewthe drag coefficient is calculated at the specific reynolds...

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ME 223 RESOURCE BOOK

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TABLE OF CONTENTS

ME 223 GLOSSARY........................................................................................................1

ACTION ITEMS...............................................................................................................4

AERODYNAMIC DRAG.................................................................................................5

BRAINSTORMING..........................................................................................................6

CONCEPT SKETCHES....................................................................................................8

DECISION-MAKING.....................................................................................................10

DESIGN ASSESSMENT................................................................................................12

DESIGN-BUILD-TEST CYCLE....................................................................................14

ENGINEERING ECONOMICS......................................................................................15

EXPERIMENT PROCESS..............................................................................................17

GOAL STATEMENT CREATION................................................................................19

INDIVIDUAL FEEDBACK...........................................................................................21

MATRIX INVERSION...................................................................................................24

LOGBOOKS....................................................................................................................27

MATH MODELING.......................................................................................................29

NEWTON’S LAWS........................................................................................................31

PRODUCT SPECIFICATION CREATION...................................................................32

PROFESSIONAL DECISION MAKING (PDM) PROCESS........................................34

PROJECT NOTEBOOKS...............................................................................................37

PROJECT TIMELINE CREATION...............................................................................38

PROTOTYPE TESTING.................................................................................................40

PROTOTYPING SKETCHES........................................................................................42

STATISTICS...................................................................................................................43


iiiTEAM FEEDBACK........................................................................................................46

TEAM LIFECYCLE.......................................................................................................48

TEAM MEETING PROCESS.........................................................................................50

Tutorials...........................................................................................................................52


1ME 223 Glossary

Action Item: A task that is to be completed by a specific date by a specific person. Something agreed to be done as a result of a discussion at a meeting and usually recorded in the minutes of that meeting.

Agenda: A short schedule of the meeting topics, which will be followed in order to run a meeting in a logical, flowing order and cover all important items. (See resource . . .)

Assessment: (Design assessment) A determination of the quality of a design compared to a standard goal criteria. An assessment is aimed at improving the quality of the design.(Performance assessment) A determination of how well an engineer or engineering team is performing. The performance assessment is aimed at improving the performance of the engineer or engineering team.

Brainstorming: A processed used by engineering teams to generate as many ideas or solution alternatives as possible. Suggestions, however outlandish, are encouraged and pursued during a creativity session. From this, many ideas, some entirely new, are brought forward for evaluation and ranking.

Concept Design: Design that shows major components and how they work together. It is used for assessing overall design before the large of effort of detail design is started. Concept sketch: A hand drawing that is aimed at communicating an idea for a product or part of a product. It should have labels and explanations of how the product/prototype works.

Decomposition: Literally, decomposition means to take something apart into smaller pieces. Engineers will decompose design problems so that they are solving several smaller (and hence easier) problems rather than one big problem. Engineers will also decompose tasks so that the smaller tasks can be more easily completed and/or divided among team members.

Design Review: A formal, documented, comprehensive and systematic examination of a design to assess the capability of the design to meet the design requirements. This process usually identifies problems and proposes solutions.

Design Show: An event intended to present the engineering final products to the client and peers.

Detail Design: Design that works out all details and dimensions. It defines all the specific parts, dimensions, materials, fabrication, and assembly of parts before building the prototype.

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http://www.pmforum.org/library/glossary/PMG_C12.htm#Creativity

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2Detail View: Larger scale view of small parts or features in a drawing to show the detail.

Evaluation: Determination of the quality of a product by careful appraisal and study aimed at assigning a value (grade) to the product. Evaluation is a final step with no intent to improve the quality of the product.

Experiment process:A set method to plan, conduct, and report product/prototype performance data.

Goal Statement:A statement created in order to clearly and specifically define what needs to be accomplished. Goal statements should include an overall goal, as well as a list of constraints and criteria with their measurable outcomes.For Example: A project goal statement should align with the client’s needs and wants.

A math model goal statement should lay out what needs to be predicted, how it will be predicted, and the acceptable accuracy of the prediction.A product goal statement should list the specifications and their quantified values (see product specification).

Individual Feedback: Verbal communication of strengths, insights, and areas for improvement aimed at improving an individual’s performance.

Integration: The process of combining small pieces into a larger whole. This is the opposite of decomposition. Engineers will integrate people into teams, activities into plans, and parts of products into whole products.

Lock on: Continuing to use (and trying to improve) a design idea after it has been proven not able to meet the product specifications. Not considering alternative designs or design modifications.

Logbook: A record of performance, events, or day-to-day activities that contains all information related to the topic. Engineering logbooks are simply engineering thinking put on paper. For an ME 223 logbook, all notes, handouts, and engineering work should be documented in it.

Math Model: A mathematical description which will predict how an engineering product or part of the product will work. The math model uses idealizations to describe the physical world. The model may be purely mathematical or a combination of math with data.

Milestone: A clearly identified project deliverable with a specific due date.

Paper Design:A design made on paper but no prototype is actually built. The intent is to investigate a design idea without sinking a lot of effort or money into the prototypes.Phenomenon:/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

http://www.pmforum.org/library/glossary/PMG_P05.htm#Process

3An observable fact or event of scientific interest which can be investigated described and explained in scientific terms.

Process:Intentional steps that an individual or a team follows to achieve a goal. Engineers follow routine processes to improve the quality and thoroughness of their work and also decrease the time to finish the task. Engineering teams will follow processes for the same reasons and also to coordinate the efforts of all the team members. (This course emphasizes the following processes: SII, PDM, etc).

Product Specification:A specific type of goal statement that clearly and specifically lists all the necessary requirements of a product as well as the specific performance acceptability of each requirement. It should be made in table form.

Process check:Stopping a process somewhere in the middle in order to make sure the process is being followed and the focus stays on the goal.

Project Notebook: A notebook intended to be presented at a design show or design review to illustrate the documentation of engineering results and processes of a team project.

Project Timeline: A schedule line showing milestones, smaller tasks, and planNed events in a project.

Prototyping sketch: A hand drawing that is intended to be used to fabricate a prototype.

Safety Factor: The ratio of the maximum load (stress, force, pressure, etc.) that a part can withstand just before failing relative to the estimated maximum load in ordinary use.

Team Feedback:Verbal communication of strengths, insights, and areas for improvement given to the entire team in order to improve the team’s performance. The feedback is focused on how well the team worked together, rather than on how well one individual team member performed. (Team feedback is analogous to how well a sport’s team “runs plays”).

Team Meeting:Structured meeting of teammates to organize, do, and/or review the project, which follows an agenda and is recorded in the “meeting minutes” of the project notebook.


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4Action Items

Overview: “Action Items” are tasks that are to be completed by a specific date by a specific person. Something agreed to be done as a result of a discussion at a meeting and usually recorded in the minutes of that meeting. Engineers use action items at team meetings to delegate tasks and responsibilities for a large team project.

Purpose:Action items help speed up progress on team projects by making sure all team members accomplish specific tasks between meetings. By reviewing action items, teams can keep better track of their progress on a project, and how much time different tasks take. They are also a good method to delegate work evenly. Action items along with documentation of completion in logbooks are an easy and effective way to hold teammates accountable for their share of the work.

Who: Every member of the team should have their major tasks specified by action items set by the team.

When:Action items should be assigned at the end of every team meeting. They should be reviewed at the beginning of every team meeting.

Why should I bother using action items?1. You have access to a simple list of “your jobs.”2. There won’t be any confusion about who was supposed to have done what. You and your

teammates can just review the action items to clear up any disagreement.3. It’s an easy method to check progress in case a teammate is falling behind.

How are Action Items used?Questions to guide you through using action items:

1. What work do we want to get done by next meeting?2. Who wants to do which task? Did everyone make a list of their action items?3. Are the tasks split up evenly? Will everyone spend about the same amount of time?4. Is each action item SMART? Review each action item to meet the criteria below.5. Are the action items recorded in the project notebook?----------------------------time to complete action items--------------------------------------------------6. Did everyone report their completion of their action items?7. Was the deliverable for each action item added to the notebook?

If you can’t finish on schedule on an action item, alert the team and have the team make a back-up plan or action item.

EXAMPLE: “Steve’s AI: Complete and debug the input module for the velocity math model by 9/22.”

Assessment CriteriaYes/No checklist Each Action Item should be:

Specific. Each Action Item should list a specific task and have a single owner. Measurable. Each task should have a concrete deliverable upon its completion. Attainable. The task is scoped so the owner can complete it in time. Results oriented. The task should work toward completing the team goals. Time bound. The task must have a specific completion date.



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5Aerodynamic DragOverview: The drag force on a body moving through a fluid is expressed in terms of two non-dimensional terms: Reynolds Number (Re) and Drag Coefficient (CD).

Fluid Mechanics NomenclatureThe following are the abbreviations that are commonly used fluid mechanics:

ρ = Density of fluidD = Diameter, or other characteristic sizeCD = Drag CoefficientFD = Drag ForceA = Projected area of deviceRe = Reynolds numberμ = Dynamic Viscosity of fluidv = Velocity of fluidSTP = Standard Temperature and Pressure

Aerodynamic Drag Equations

Equation Assumptions1. The flow is steady. There is no pulsating or grossly unsteady flow.2. The drag coefficient is calculated at the specific Reynolds number. There is no guarantee that

drag coefficient is constant.3. For the drag coefficient equation, the object is a sphere with Re between 101 and 103.

Useful InformationDensity of air at STP = 1.229kg/m2 Viscosity of air at STP =1.73 *10-5Nּs/m2 Graph of CD vs Re:


6Brainstorming

Overview: Brainstorming is a process used by teams to generate as many ideas or solution alternatives as possible. Suggestions, however outlandish, are encouraged and pursued during a creativity session. From this, many ideas, some entirely new, are brought forward for evaluation and ranking.

Purpose:Brainstorming in a group of people produces lots of extremely creative ideas really fast. Brainstorming encourages team members to feed off of each others creative ideas to come up with better and more innovative ideas.

Who: Teams who need several “seed ideas” to begin looking at alternative solution paths to a problem use brainstorming.

When:Brainstorm whenever you want to generate lots of ideas and/or creative ideas. You can brainstorm an idea about anything: a process to run a meeting, a method to remember important information, a design solution, and analysis method, project risks, etc. Brainstorming is most useful when first starting a project or when present alternatives are not adequate.

Why should we bother brainstorming?1. A group of people brainstorming come up with more ideas, better ideas, and more creative

ideas faster than a single person can.2. It is important to come up with alternative solutions to a problem, in case the solution path you

start to follow leads to a dead end.3. Brainstorming helps prevent you from getting “locked on” to a solution that won’t work.4. Brainstorming is fun!

How is a brainstorming session run?Rules:

1. NO EVALUATING: Never comment about why or why not an idea will work. Evaluation and/or assessment come later. All ideas are accepted as being equally valid until the brainstorming session is ended.

2. Be loud and flashy: Present and explain your ideas somehow so the entire team can see them and hear you. Drawing on paper and presenting it on a wall is a good method to do this (and it will help you organize your evaluation later).

3. Document: Record all your ideas for your project notebook. A team member can take notes, you can take a picture of the board as long as it’s clear, you can collect the paper you drew on and add it to your project notebook.

Guidelines:1. Time: Keep sessions going as long as the ideas keep flowing. They usually run 3-10 minutes. 2. "Piggy-backing" allowed: Take someone else’s good idea and add to it or modify it.

Quantity Wanted: Generate as many ideas as fast as you can. Express them even if they don’t seem like a very good idea. If only 1 in 10 ideas is good, it makes sense that the more ideas on the table, the greater the odds of having several first-rate ideas to choose from. Hint: more enthusiasm equals more ideas.


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73. Wild Hairs: Encourage and work off of crazy ideas. Sometimes the craziest ideas will create a

new view of the situation and although they may not directly provide a solution to the goal, they often redirect thinking in a path that would never have been discovered without the "wild hair."

What comes next?After the brainstorming session is finished, you can evaluate and assess the ideas. Often times, teams decide on a few ideas or groups of ideas to develop further. Refer to the “Design Assessment” Resource for how to assess your ideas and the “Decision-making” Resource on how to make engineering decisions. Sometimes the goal of a brainstorm is to create a list. In this case, evaluation may not need to be done, or it simply consists of the team agreeing to drop a few items that don’t fit in the list. There are several possible next steps:

1. Combine the best ideas to come up with one or more new ideas that incorporate the best aspects of the brainstormed ideas.

2. Team vote on best idea(s) to design in more detail.3. Team discussion and consensus of best idea(s) to design in more detail.4. If the goal of the brainstorm were to come up with a list, drop the ideas that don’t fit the list.


8Concept Sketches

Overview: “Concept Sketches” are hand drawings that are aimed at communicating an idea for a product or part of a product. It should have labels and explanations of how the product/prototype works.

Purpose:Creating a concept sketch is an important step in communicating and assessing ideas before pursuing detail design. Drawing a concept on paper is a great method to communicate ideas to your teammates, clients, and boss. Engineers need to be able to visualize a concept spatially in order to fully understand it.

Who: Engineers and engineering teams use sketches to work out a concept design before spending time creating the detail design.

When:A concept sketch can be made every time you want to communicate an idea for a physical design. They can be used during a brainstorm, to develop a preliminary idea further, to combine ideas into a new one, and when you want to communicate an idea for a prototype improvement.

Why should I bother creating a concept sketch?1. Communicating ideas is difficult. Most people understand better and faster if they have a

picture to look at.2. It saves time!3. Design bugs are discovered sooner.4. They help plan how to create a prototyping sketch.5. They are an excellent way to document your design process.6. They are an easy way to keep track of improvements made in the product along the way.

How are excellent Concept Sketches created?1. Draw what your idea looks like.2. Write out how the idea works.3. Label all the parts.4. Write how each part works with the whole.5. Show it to your teammates.

Assessment CriteriaYes/No checklist Each concept sketch should:

Have labeled parts. Visually represent the idea well enough for someone unfamiliar with the design to know what a

prototype would look like. Explain the idea well enough for someone unfamiliar with the design to understand how the

prototype would work by looking at the sketch. Be drawn large enough to distinguish important features. Show all important features.

*Refer to the example on the next page for some more guidance.


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InsertConcept sketch example

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10Decision-making

Overview: Engineering decision making is an important process that often gets overlooked. Deciding which ideas are worth pursuing is an extremely difficult and significant part of the design process. There are several methods for engineering decision making; three are presented below: Individual decisions, team voting, and team consensus.

Purpose:Design decisions are often made without documenting or understanding the reasoning behind them. However, clients and bosses are usually most interested in how and why design decisions were made. Using a set process to make engineering decisions promotes well documented, high quality decisions.

Who: Every good engineer and engineering team uses the right decision-making process for each situation.

When:There are three major points in a project when design decisions need to be made:

1. After a brainstorm to decide the best ideas or set of ideas to pursue as “concept designs.”2. After the concept designs are developed to decide the best one to pursue as a “detailed design.”3. During design assessments to decide how to improve the prototype or what ideas the next

iteration should incorporate.Other instances of team decisions on:

1. When to meet.2. When to build a prototype.3. When to review deliverables.4. Who does what role.

Why should I bother using a set decision-making process?1. Your boss will want to know why you did what you did. Having your decision making process

documented and well laid out will not only satisfy but impress him or her.2. Making a fair team decision is always difficult unless you have a process to follow.3. Using a set process will help you or your team make a better decision than you could do

without a process.4. Using good decision making processes strengthens a team, whereas poor decision making

processes can divide a team.5. You can prevent making bad or arbitrary decisions.

How do I make an excellent engineering decision?No matter which method below you use, it is always important to base your decision on design assessment and solid reasons based on the product specifications and/or goal criteria, and not on opinions. Refer to the “Design Assessment” Resource for guidance on assessing designs, ideas, and concepts.

Individual DecisionsIndividual decisions are quick and painless, but they are the easiest ones to forget to document. When making individual decisions, remember to base them on solid assessment. Record how and why you make every decision in your logbook.


11Team votingThis process is most valuable following a brainstorm. This is the step when you evaluate the brainstorming ideas by voting for the ideas you think were the best. There are a few different ways to go about team voting, but the important thing to remember is to compare the ideas to the product specifications and/or criteria set out in the goal statement. Sometimes it’s best to vote directly after the brainstorm, sometimes it’s better to combine, discuss, and explain the ideas before voting. A good method for voting is to have each team member vote for 2-4 ideas and then the ideas with the highest number of votes win. The results of team votes should always be documented in the project notebook.

Team Consensus Team consensus is an important method to use when a decision affects all the team members, particularly when choosing a concept design for the entire team to move into detail design of. It usually involves lots of discussion of strengths and weaknesses of the options(usually concepts). Consensus is “win-win” or “no-deal.” The decision must work for every team member.


Method Strengths Weaknesses When to use

Individual DecisionsQuick Limited to

knowledge of individual.

For individual work.When results are “low stakes.”

Team voting“Fair” and quick Win-lose. Some

ideas/people may get “railroaded.”

Many meeting processes.Following a brainstorm.

Team ConsensusBuilds team. Higher quality decision.Everyone has buy-in to design.

Takes the most time and effort.

“High stakes” choices.When all team members are affected.

12Design Assessment

Overview: “Design Assessment” is a determination of the quality of a design compared to a standard set of product specifications and/or goal criteria. An assessment is aimed at improving the quality of the design.

Purpose:Design assessment is used determine the quality of a design or design idea. It can be aimed at improving an existing design or helping decide the best ideas to pursue as concept designs or detail designs.

Who: Engineers and engineering teams use design assessments to ensure a high quality design is produced at the end of their project.

When:There are four major points when design assessments needs to be done:

1. After a brainstorm to assess the ideas or sets of ideas to choose which to pursue as “concept designs.”

2. During and after a paper design to improve the design.3. After the concept designs are developed in order to choose which to pursue as a “detailed

design.”4. When prototypes are finished to determine how to improve the design, which aspects of the

design are good, and which need improvement or to be “thrown out.”

Why do design assessment?1. It saves time! If you do design assessments early you can catch design bugs sooner.2. Get a great product! Constantly comparing your design to high quality product specifications

and/or goal criteria will help you improve the quality of your final product.

How is design assessment done?The most important thing to keep in mind when doing a design assessment is to compare the design to the product specifications and/or goal criteria. There are several methods to assess designs. A few are listed and explained below:

INDIVIDUAL REVIEWIndividual review is most useful after a brainstorm. It is probably the fastest way to assess a design. The method is simple: qualitatively think about how well each design idea will meet the product specifications and/or goal criteria. This assessment is usually coupled with a team vote or with a small individual decision or design. Sometimes creating a prioritized list of ideas helps the decision or next design iteration.

TEAM REVIEWTeam review is most useful after a brainstorm or during a decision about concept designs. The method is similar to individual comparing except the team discusses and reaches a consensus about how well the design will meet the product specifications and/or goal criteria. Sometimes creating a prioritized list of ideas helps the decision or next design iteration.


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13PROTOTYPE TESTINGPrototype testing is usually the easiest and most thorough way to assess how well the design meets the product specifications if a working prototype has been created. The process is described in the “Prototype Testing” Resource.

THE ENGINEERING DECISION MATRIXThis process is most valuable after the concept designs have been developed. It takes more time than individual or team reviewing, but produces a more thoroughly thought-out decision. The steps are as follows:

4. Create your matrix: List your decision factors down the left side of the matrix, and the concept ideas across the top. The concept ideas should be labeled as short descriptions of the idea, not “concept 1.” The decision factors can usually come directly from your product specifications and/or goal criteria. Some examples of decision factors are: weight, cost, time to build, performance, etc.

5. Weight each factor: Rate how important each factor is to the team on a scale of 1 to 10. In the example below, the time it takes to build was the most important so it receives a weight of 10, whereas the cost of the product doesn’t matter very much so it receives a weight of 3.

6. Fill in the matrix: Score each concept for each criterion on a scale of 1 to 10 (the columns under the concept heading).

7. Compare scores: Total the score of each concept by multiplying the weight of the factor by the score the concept received for each cell (column to the right of each concept), sum (total score row), and average(weighted average row). This step sounds complicated but it’s not. In the example, concept 1, “Mouse Trap” scored 3, 8, and 4 on factors weighted 5, 10 and 3. Its summed score is 6*5 + 8*10 + 4*3=122 divided by the total of the weights of 18 equals the weighted average of 6.78. Each concept will receive a weighted average that you will compare. The highest weighted average will be the best concept. In the example below, this was “Mouse Trap” whose score is in bold.

EXAMPLE:


14Design-Build-Test CycleOverview: Design is probably the single most important professional development outcome of this class. Teaming, math modeling, and project management are all tools to help you design a great product. The “D-B-T cycle” is the tool to walk you through the steps of design. The key to this process is repetitively improving your design through assessment and iteration.

Purpose:The goal of the D-B-T cycle is to organize each prototype iteration into a process.

Who: Engineers use the design, build test cycle to increase efficiency, results, and thoroughness.

When:Use the D-B-T cycle for each prototype iteration, after you create your product specification for each iteration.

Why follow a D-B-T cycle?1. It saves time by increasing the quality of each iteration.2. You’ll end up with a higher quality product.

How is the D-B-T cycle done?There is an iterative design process to follow with these steps:

Design Concept

→ Assess Concept

→Design Detail

→ Assess Detail

→ Redesign → Build → Test

1. Design Concept: There are several methods to create concept designs, but the important thing to remember is that you need to come up with several alternatives. “Lock on” is one of the biggest threats to creating an excellent design. Refer to the “Concept Sketches” Resource for more guidance.

2. Assess Concept: Most of the time it will work to assess the design on paper, but sometimes you may want to build quick prototypes of the concepts in order to test them. Always remember to compare the design idea to the product specification while assessing. Refer to the “Design Assessment” Resource for more guidance. Come up with a “new and improved” concept on which to base the next step.

3. Design Detail: This is the stage where all the details of the best concept design (or combination of designs) are worked out. You should create a prototyping sketch for this step that shows all the dimensions and materials. You should create a plan for how to build the prototype and a test plan for the finished prototype.

4. Assess Detail Design: This step is incredibly important to the design process. The goal of the assessment is to find errors in details before building it. Sometimes design flaws will also be discovered at the detail design review.

5. Redesign: This step is based on your detail design assessment. Incorporate the improvements you thought of in the assessment into a new or refined design. This step incorporates the last small improvements before building. You must should create a new prototyping sketch during this step and update your building plan.

You may want to repeat steps 4 and 5 if design flaws are discovered6. Build: This step is self explanatory, however, it is important to follow your prototyping sketch

and building plan.7. Test: This step is often done without much methodology, but it is important to follow a

process and record your quantitative results. Refer to the “Prototype Testing Process” Resource for more guidance.


15Engineering Economics

Overview: Engineering economics is an important skill to learn because, as in most things, money ends up being a major deciding factor when making engineering decisions.

Engineering Economics NomenclatureThe following are the abbreviations that are commonly used in engineering economics:

P = Present value (measured in dollars today)A = (Annual) Uniform periodic payments or income (like a monthly car payment)F = Future value (measured in dollars on a future day)n = number of time periods (e.g. having 48 monthly car payments)i = interest rate (simple compounding at time intervals corresponding to n) (e.g. 10% =0.10)

Example: Suppose you took a $1000 loan today and had to pay it back in one lump sum of $1100 in 1 year. The present value is $1000. The future value (measured in dollars one year from now) is $1100. The interest is 10%. The number of time periods is 1. The $1000 present worth is considered to be equivalent to the $1100 future worth with the parameters given (10% interest and 1 year time period).

Cash Flow Diagram: A useful Economic Tool: The timeline is a useful tool for visualizing the problem. The timeline is sometimes also called the cash flow diagram.Procedures and Conventions:

1. The costs or disbursements are pointing down and proportional in size to the $ value.2. Incomes are pointing up.3. The incomes and disbursements are additive.4. All incomes and expenses are shown at the end of the year in which they occur. This

simplification is used whether the income/expense happens on day 1 or day 350 of the year.

Example: A heating system for a multi-family dwelling has an initial cost of $20,000. The yearly operation and maintenance charges are $1,000. Increased rent (to help pay for the better heating system) results in an extra $5,000 per year of income. The heating system has a life of 10 years, at which time it can be sold for $7,000.

Assuming that the costs and income happen at the end of the year (just to make life easier at the moment) then the timeline for this system is:


16Engineering Economics Equations

Equation UseTo determine how much a sum of money invested now (P) will be worth in a few years (F).To reverse the process above and calculate how much something in the future (F) would be worth today (P).To determine how large the periodic payment (A) would be for a loan or investment made now (P). For example, the cost of payments on a car loan.

To reverse the process above and determine how large a loan or investment made now (P) would be for a known periodic payment (A). For instance, to find out how expensive a car you can buy if you know how much money you’ll have for monthly car payments.To determine how large the periodic payment (A) would be for a loan or investment made sometime in the future (F). For example, how much you would have to save every month if you know you want to buy a motorcycle in 5 years.To reverse the process above and determine how large a loan or investment made in the future (F) would be for a known periodic payment (A). For instance, to find out how expensive a car you can buy if you know how much money you can save up each month.

Equation Assumptions1. All costs and credits take place at the end of the year.2. There is no inflation.3. The effective interest rate used in the problem will be constant during the lifetime of the

project.4. Excess funds continue to earn interest at the rate used in the analysis.

Example 1: Suppose you put $1000 (P) in a bank at 10% interest compounded yearly. How much would it be worth in 5 years (n)?

Solution:

Example 2: Suppose you want to find out how much you have to save each year (A) to afford a $10,000 (F) car in 5 years (n). Your savings interest rate is 6%. How much do you need to deposit in your savings account each year?

Solution:


17Experiment Process

Overview: An “experiment process” is a set method to plan, conduct, and report data.

Purpose:Using a set experiment process to collect data will ensure your data is complete, objective, and consistent throughout the project. A quick experiment is often the best way to determine the physical information for a math model or to verify a math model prediction.

Who: All good Engineers us a testing process in order to get high quality experiment data.

When:Follow this process any time you are running an experiment or testing a prototype.

Why should we follow an experiment process?1. It saves time. You could omit an important step like recording your data and have to redo it.2. It ensures the data is valid. It’s important the data you collect and report is correct.

How is a high quality experiment run?Rules:

1. Document: ALWAYS document your experiment in your logbooks.a. Include an experiment sketch.b. Record your data as you collect it in a clearly labeled and organized table.

2. Plan: Plan your experiment before you start.a. What information are you looking for? b. What are the dependant and independent variables?c. Plan to take enough data to ensure you know what the numbers mean. d. Write up a test procedure listing the steps to take the measurements.

3. Collect objectively: Make sure your results aren’t skewed by your expectations. a. If you have to, ask a friend or teammate to take the data while you record it.b. It’s also important to stay consistent in how the data is collected.

4. Analyze: Analyze the data.a. Usually the data should be entered in a spreadsheet and mathematical/graphical

operations performed.b. Make sure the numbers you end up with have the corresponding significant digits to the

instruments you used to measure the data. 5. Interpret: Interpret the data in a report.

a. Scope the report to fit the importance of the experiment. It can be 1-10 pages.b. What does the data mean? How does it compare to the calculated predictions.c. Format the report to fit the criteria below.

Format:1. Goal2. Equipment3. Methods4. Results5. Conclusions


18

Report Assessment CriteriaYes/No checklist Each experiment report should have:

1. Descriptive title line of the experiment.2. Experiment description section: Brief description of how the data was collected. List your

procedure and paste in your sketch (if applicable).3. Data analysis section: Create histograms, calculate means, create best-fit lines, etc.4. Mathematical Prediction section: Briefly describe the process you used to predict (if

applicable).5. Results summary: Brief summary comparing the predictions to the measured data.6. Appendix Attachments: Single page attachments. One attachment per data set. Each

attachment should be clearly titled and easy to read. All graphs should be well labeled.

Logbook Documentation Assessment CriteriaYes/No checklist Logbook documentation should have:

1. Descriptive title line of the experiment with date.2. Experiment sketch: Detailed sketch of the experiment including labels of all apparatuses.3. Procedure: Each step and any modifications are listed in your logbook.4. Data Collection Table: Make sure the table has a title, clearly labeled rows and columns, units,

and the correct resolution on measurements.


19Goal Statement Creation

Overview: Goal statements clearly and specifically define what needs to be accomplished. Goal statements should include an overall goal, as well as a list of constraints and criteria with their measurable outcomes.

Purpose:The purpose of creating a goal statement is to clearly define the end goals of a project or problem. The goal statement is a written document of what both the engineers and the clients expect to be delivered at the end of a project.

Who: While most engineering projects begin with a starting point such as a project assignment, the engineer needs to create an appropriate goal. That is, a goal that will solve the real problem if it is achieved.

When:Goal statements should be created when starting a project or problem. Creating goal statements for projects is an iterative process that involves assessment by your client and/or boss. For goal statements for a product, refer to the “Product Specification Creation” Resource. For goal statements for math models, refer to the “Math Modeling” Resource.

Why bother creating a goal statement?1. It saves time! Creating a goal statement will keep you focused on your deliverables.2. Get alignment with your boss and client early. Everyone knows what is expected of you or

your engineering team. There won’t be any “curve balls” part way through the project. There’s nothing worse than thinking you completed a project to find out you didn’t actually do what your boss or client wanted.

3. Goal statement criteria (outcomes, objectives) provide easy reference for measuring the performance of your results.

How is a goal statement created?Steps:

1. Find the Problem: Identify the most important problems and constraints associated with the project.

2. Draft the Statement: Each criterion (objective) should be a direct response to the issues identified in problem finding. Each criterion should be measurable. Each metric should be simple, valid, and reliable. Constraints should consider issues such as cost, codes and standards, fabrication, manufacturing, safety, and client interests that must be met. Keep the entire statement to less than one page.

3. Assess: Meet with the client, team members, users, and other stakeholders to present the goal statement. Ask for honest and detailed feedback. Ask many questions: Will these results satisfy everyone? Are they attainable? Are the metrics thoughtful and clear?

4. Iterate: Repeat steps 1 to 3 (usually 2-3 iterations are best). Keep each iteration simple and think of adding quality with each iteration.

5. Design Review: Present the final goal statement to all relevant stakeholders. Present evidence that the goal statement is high quality. Obtain agreement not to change the goal statement, fixing it in place so that the design team is not trying to hit a moving target. Present a plan to ensure that the goal is used to drive the rest of the design process.


20

Tips:1. Avoid “goal creation hell”. When the process gets too complex or overwhelming, this is a

signal to reduce the level of detail. Some ideas are to (a) focus on the top 2-3 criteria, and (b) to avoid perfectionism by focusing on completing a series of draft statements.

2. Avoid “goal triteness”. When the process seems obvious or trite, this is a signal to dive deeper into the task. Goal creation requires deep thinking and iteration.

3. Measure connection. The quality of a goal statement can be quickly tested by the response of people such as team members, users, and the client. When the goal statement is beginning to possess quality, then people who hear and understand the goal statement will respond in highly positive ways. For example, team members and clients will be excited to move forward with the project and will be unified in this interest. Users will ask when they can buy the product.

4. Problem finding. The quality of a goal statement is directly related to the real problems and opportunities that are connected with the project. It is a means, not an end in itself.

5. List the problems/criteria in order to identify the most important.

Assessment CriteriaMuch like action items, goal statements need to be SMARTYes/No checklist for a goal statement:

Specific: The goal statement is specific enough that everyone knows what the deliverables will be. The language is clear and concise.

Measurable: The goal criteria are measurable Attainable: The goal is attainable Results oriented: The goal is a result, not a method Time-bound: The goal statement specifies a clear deliverable date.


21Individual Feedback

Overview: Individual Feedback means to give another teammate your insights into his or her performance. The individual feedback is given face-to-face so that the recipient may ask you to clarify any statements. Care must be taken when giving a teammate individual feedback.

Purpose:Feedback is always given with the intent of helping your teammate to improve his or her future performance. The feedback is not about the past—what he or she did or failed to do—but rather about what they can do in the future.

What type feedback should be given?You should give your teammates feedback on their strengths, their areas for improvement, and insights into their performance that they would probably not notice themselves. Feedback about their strengths should be given more frequently than feedback about weaknesses and other insights.

Who: Every good engineer gives feedback to their teammates and seeks feedback from their teammates.

When:Feedback should be given routinely, rather than being “saved up.” Common times to give feedback are at the completion of tasks, at the end of every meeting, and at regularly scheduled checkpoints.

Why should I take the risk of giving feedback?1. You can prevent small problems from growing into HUGE problems by resolving concerns as

they arise.2. You can improve team dynamics for high team performance early and throughout project.3. You can grow team performance by identifying individual strengths (assign experts to strength

areas).4. You and your teammates will improve your performance, increasing overall team performance.

How is excellent feedback constructed?Take care to make sure your feedback is:

1. Well Balanced: You should always give more strengths than areas for improvement. When a team first starts giving individual feedback, the ratio should be 3 to 1. As individual feedback skills improve, you can decrease the ratio as low as 3 to 2. Always start feedback with Strengths.

2. Specific: Phrase your feedback so it describes a specific action or process performance, so the receiver has a clear context to understand. Also explain how the improvement will help the team.

3. Focused on observation: It is easy to jump from observable performance to inferring why the receiver was performing the way they were. Assuming what someone’s motivation or intentions are alienates the person. It is dangerous to assume we know why someone performs the way they do or what they were “really” trying to do. It can lead to a climate of resentment and distrust and does not lead to improvement.

4. Focused on behavior: Focus your feedback on what a person does rather than what you may think the person is.


225. Accounting for needs of receiver: Make sure your feedback is focusing on helping the

receiver improve, rather than your needs to vent frustration.6. Forward focused: Direct your feedback on behavior receiver the receiver can do something

about. It is extremely frustrating to be reminded of shortcomings over which the receiver has no control. Make sure to phrase your feedback in context of the future.

7. Solicited: Feedback is most useful when the receiver actively seeks feedback. Never give unplanned feedback without asking if it is wanted first.

8. Objective: Make sure the insights you give share information rather than give advice.9. Well-timed: Immediate feedback is usually most useful. Excellent feedback given at the

wrong time may do more harm than good.10. Well scoped: Make sure the amount of information you give allows the receiver to use it

effectively. Too much information can overload the receiver into inaction.

What does an excellent engineer do when receiving feedback?1. Solicit feedback often, especially if you are uncertain of the quality of your performance.2. Rephrase feedback to ensure clear communication.3. Take good notes in their logbooks.4. Decide what is true, what is partially true, what is not true.5. Decide how to improve future performance based on the feedback.

Assessment Criteria-3: Detrimental to team1: Beginning level Engineer 3: Working level Engineer 5: “Expert” level Engineer

Attribute -3 1 2 3 4 5Behavior Focused

Feedback focuses on who a person is.

Feedback focuses on what the person does.

Specific Feedback is vague or general

Feedback clearly states specific actions

Feedback clearly notes specific details of the action

Forward Focused

Feedback is phrased negatively and blames the receiver.

Feedback does not mention how to improve.

Feedback gives vague ideas of how to improve

Feedback has a clear improvement plan.

Rationale (not motive)

Feedback guesses at the receiver’s motivation for an action.

Feedback does not mention why the action helped/impaired.

Feedback hints at why the action helped or impaired performance.

Feedback clearly states why the action helped or impaired performance.

Balance The feedback was more improvements than strengths.

The feedback has about the same amount of strengths as improvements.

The feedback has more strengths than improvements.

The feedback has the most effective ratio of strengths to improvements.

Distribution One team member dominates the discussion.

Some team members do not give feedback.

All team members give some feedback.

All team members give equal amount of feedback.

ScopeThe receiver is overwhelmed at the amount of improvement he/she needs to make.

The receiver has too little information to take significant action to improve.

The receiver can use the amount of information to improve.

The receiver can effectively use the amount of information to improve.

Checked for Clarity

The receiver misunderstands the feedback.

The receiver generally understands the feedback without checking.

The receiver checks to generally understand the feedback.

The receiver ensures they understand the feedback by clearly rephrasing.


23EXAMPLE: Strengths:

1. “Steve, your work on the Matlab code last week really helped the project progress. It was high quality, fast, and you printed out a great-looking version for the project notebook.

2. You have done a great job with documenting other work in your logbook and the project notebook as well, like your solution to the aerodynamic math modeling problem.

3. You also have been communicating well via e-mail on updates of your work.”Improvements:

1. “An improvement you could make would be to attend the team meetings on time, so the team can update and assign action items more effectively. Last time you were late, which slowed down our meeting progress.”


24Matrix Inversion

Consider the following three linear equations:

2x1 + 2x2 + 3x3 = y1 5x1 + 2x2 + 7x3 = y1 0x1 + 1x2 + 2x3 = y1

These equations could be written in matrix form as:

2 2 3 x1 y1

5 2 7 x2 = y2

0 1 2 x3 y3

Or the equations could be written as:

Ax = y

Where A is the square matrix with the coefficients, and x & y are the column vectors.

Usually the values in A and y are known, and the values in x are to be found. To find the values in x, consider the following steps:

I*Ax = I*y Multiply both sides by the identity matrix

Ax = Iy Simplify both sides

Remembering that these matrices really represent a group of linear equations, we can manipulate the equations just as we would in algebra. For example, we can multiply both sides of any equation by a number. Comparing the matrix form to equation form the rules we will use are:

Equation rules Matrix equivalent rules

Multiply both sides of an equation by a number

Multiply all the numbers in the same row in A and I by the same number. (Note: as soon as we multiply a row in an identity matrix, it is no longer an identity matrix and we should use a different letter to represent it.)

Subtract one equation from another Subtract the numbers in one row of A and I by the corresponding numbers in another row of A and I. (Again, the matrix would be better named something other than I once it is no longer and identity matrix.)

With the above two rules in place, we now want to manipulate the expression…

Ax = Iy/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

25

…until A is converted into an identity matrix. When this is completed, the matrix I will no longer be an identity matrix, so it will be called A-1. The equation will then become:

Ix = A-1y simplifying yields…

x = A-1y

Note now that A-1 is the inverse matrix of A.

Now let’s turn the discussion above into a standard procedure for inverting a matrix. I’ll demonstrate this using the original matrix as an example.

Step 1: Create an identity matrix the same size as the matrix to invert. If you are doing this by hand, set the two matrices side by side.

2 2 3 1 0 05 2 7 0 1 00 1 2 0 0 1

Step 2: Use the value in the upper left corner of the first matrix (in this case 2) to turn the numbers below it (in this case 5 and 0) into zeros. We will call the “2” the pivot. Let’s start by doing this to the second row.

Step 2a: Multiply every number in the second row in both matrices by 2/5. This yields:

2 2 3 1 0 02 0.8 2.8 0 .4 00 1 2 0 0 1

Step 2b: Note that the identity matrix is no longer an identity matrix. Now subtract the second row from the first and put the resulting differences into the second row. This yields:

2 2 3 1 0 00 1.2 .2 1 -0.4 00 1 2 0 0 1

Step 2c: Note how the first number in the second row is now zero. Also note how the identity matrix has a non-zero term that is off the diagonal. We now need to get turn the first number of the third row into a zero using the same pivot as before. However, this number is already a zero, so we can skip this step.

Step 3: We now take the 2nd number in the 2nd row (1.2) and make it our new pivot. Using this pivot, we turn all the numbers below it in the 2nd column into zeros. We use the same procedure as in step 2 and get:

2 2 3 1 0 0/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

260 1.2 .2 1 -0.4 00 0 -2.2 1 -0.4 -1.2

Step 4: We continue doing the same procedure using the numbers on the diagonal for successive pivots until the matrix is “upper-triangular”, that is, all the numbers below the diagonal are zero.

Step 5: We now want to turn the numbers in the last column, above the diagonal (in this case .2 and 3) into zeros. Using the 3rd number in the 3rd row as a pivot and working upward we turn the 3rd number in the 2nd row into a zero. This gives us:

2 2 3 1 0 00 13.2 0 12 -4.8 -1.20 0 -2.2 1 -0.4 -1.2

Doing the same trick again to turn the 3rd number in the 1st row to zero (still using the -2.2 as a pivot) gives:

1.467 1.467 0 1.733 -0.4 -1.20 13.2 0 12 -4.8 -1.20 0 -2.2 1 -0.4 -1.2

Note that the zeros below the diagonal on the original matrix are still zero. This is important because we want to turn the original matrix into an identity matrix with zeros every place except on the diagonal.

Step 6: Use the 13.2 as the pivot to turn the 1.467 into a zero. This gives:

-13.2 0 0 -3.6 -1.2 9.60 13.2 0 12 -4.8 -1.20 0 -2.2 1 -0.4 -1.2

Step 7: We are almost done. The matrix on the left is now “diagonal”, that is there are zeros in every place not on the diagonal. The final step is to turn the matrix on the left into an identity matrix. We do this by dividing every element in each row by the value of the pivot on that specific row. So on the 1st row we divide every element by -13.2, on the 2nd row we divide every element by 13.2, and on the 3rd row we divide every element by -2.2. When we do this we get:

1 0 0 .273 .091 -.7270 1 0 .909 -.364 -.0910 0 1 -.455 .182 .545

The matrix on the right is now the inverse of the original matrix.

Logbooks


27Overview: “Logbooks” are a record of performance, events, or day-to-day activities that contain all information related to the topic. Engineering logbooks are simply engineering thinking put on paper. For an ME 223 logbook, all notes, handouts, and engineering work should be documented in it.

Purpose:Logbooks are used by engineers to document their engineering ideas, designs, research, meeting notes, analysis, etc. Writing regularly in a logbook improves engineering performance by promoting self-assessment, following processes (like PDM), process checks, and time management. Logbooks are important for engineers to be able to review their past work and notes for reference.

Who: High performing individuals in all professions are similar in that they monitor and control where they invest their time, they learn and apply the best practices their profession, and they regularly take time to learn from their successes and failures. When:Logbooks should be used constantly:

1. Log personal activity, communications, and team activity.2. Document research and engineering analysis.3. Take class and meeting notes.4. Organize class work, handouts, and resources.5. Reflect on individual/team/product performance.

Why should I bother keeping a logbook?Logbooks are an excellent tool to:

4. record ideas5. improve ideas6. communicate ideas7. keep yourself on track.8. manage your time.9. organize all of your documents.10. prove how much work you have done on a project.

How do I keep an excellent Logbook?8. Document EVERYTHING in your logbook.9. Use a heading for each new topic with a consistent format

For example: 9/1/04 Class Notes: PDM process

10. Leave enough white space in your notes so that they are easy to read.11. Start each activity or task by quickly writing out the goal, time allotment, and a plan to reach

the goal in your logbook.12. Document your work on the activity in your logbook.13. Review your goal, time spent, and plan when you finish the activity (possibly at intermediate

steps for process checks) to check if you followed it and met your time management goals.


28Assessment CriteriaYes/No checklist Your ME 223 Logbook should have:

A table of contents. Labeled sections (Class handouts, class notes, meeting notes, independent work log, etc.). Headings with: consistent format, date, topic. A record of everything you worked on, read, or received for this class. Entries with details of design, analysis, and design assessment. Charts, data, and/or sketches that meet the assessment criteria in the “Experiment Procedure,”

“Prototyping Sketches,” and “Concept Sketches” Resources. Documentation of all design decisions. Organization and white space that make it easy to read.

Assessment RubricEntry Type Characteristic “Low” “Medium” “High”

General Qualities

Writing Sloppy, hard to read

Mostly legible Read with ease

Layout Random, disorganized

Clear layout Layout helps understanding

Headings & Dates

No headings or dates

Some heading and dates

Heading and dates stand out

Sketches and Diagrams

Neatness Sloppy, smudged Clear Very clearDetails Few details Most important

detailsAll important details

Labels Unlabeled Most items labeled Everything labeledCharts and Graphs

Neatness Sloppy, smudged Clear Very clearAxes labels Unlabeled Labeled Labeled with units

Written Notes Content Confusing, too brief

Clear but some missing information

Clear, contain all relevant information

CalculationsComment No reference to

picture or problemReferenced to picture or problem

Part of a larger explanation.

Units No unit analysis Some unit analysis Units carried throughoutSteps Big jump from

equation to answerMost steps are shown

All steps are shown

Team Logistics

Action Items Minimal entry Nearly complete entry

Specific deliverable, with due date

Project Timeline

Little detail or way too much detail

Most important activities are tracked

All important activities are shown with deadlines

Experiments Background Little information Most information Contains goal, equipment, data, conclusions

Reflections Frequency Never Occasional RoutineContent Superficial Describes actions Describes insights


29Math Modeling

Overview: A math model is a tool that Engineers use to verify that their designs will work reliably and safely. The basic model looks like this:Physical world Conceptual world Mathematical world Calculation tool Interpret numerical results

Purpose:The main goal of a math model is to predict the performance of an engineering system using math.

Who: Engineers use math modeling in design.

When:Math models are used from the initial design phases all the way through the final product testing. The steps below are excellent guides to completing a math model but do not necessarily have to be done sequentially. For example, your boss or client may already know the important physical phenomena and the relevant physical information associated with them, so you would log this information as the first step and fill in the appropriate information when you get to steps 3 and 6.

Why should I bother creating a math model?1. It saves time! If you use a math model to make predictions and design decisions, you’ll spend a

lot less time building and testing, because your test results will reflect your math model rather than guessing.

2. Math Models are often the most valid basis for design decisions, like how large to make the water chamber in a rocket, or the parachute in the re-entry device.

3. If you don’t create math models when appropriate, you are not doing engineering.

How is a high quality math model created?Step 1—Write a goal statement for the math model

Clearly identify what you need to mathematically predict and why you need to predict it. Clearly identify how the prediction will be used. Clearly identify the lowest acceptable prediction accuracy for the model.

Step 2—Create a sketch Sketch the entire device showing all parts. Partition the system into simple pieces with identified boundaries between them as necessary. Sketch to scale. Is this necessary? Not all modeling needs a high quality sketch.

Step 3—Identify and prioritize significant physical phenomenon list of physical phenomena

List important physical phenomenon (based on your intuition) in order from biggest effect to smallest effect.

Label the phenomenon on the drawing, showing sign conventions (use arrows).

Step 4—Identify equations and the underlying assumptions that model the physical phenomenon


30 List modeling equations and corresponding assumptions together. Label the coordinate systems, origins, and directions on the sketch.

Step 5—Verify the underlying assumptions for each modeling equation. Verify that the equation assumptions match the assumptions in your sketch. (For example: how

often have you seen in a physics problem “assume a frictionless surface” when in real life you knew friction was a big part of the physics?)

Step 6—Find the relevant physical information Physical properties of materials are found. Simple measurements (size, mass, spring rates, etc.) are made of device being modeled.

Step 7—Plan and implement an analytic or numeric solution to the equations Carry and cancel units. Make sure they balance. Check your numerical accuracy.

Step 8—Verify that the prediction makes sense. Examine the predicted value to see if it appears reasonable in value. Try the model on a simple case to make sure it works.


31Newton’s Law

Overview: Newton’s Law relates position, velocity, acceleration, time, and force. NOTE: These are not energy method equations.

NomenclatureThe following are the abbreviations that are commonly used for Newton’s Law:

F = Forcea = Accelerationm = Massv = Velocity (speed with direction)x = Distanced = Infinitesimally small “change in”Δ = “Change in” or time step

Equations of Newton’s Law Equation Use

1. Always true at every moment. HOWEVER, must know the true forces.

2. This equation is a definition. Therefore, it is always true. Differential equation.

3. This equation is a good estimate if the change in time is “short enough.”

4. Always true. This equation is just the first equation with the second equation substituted in for a. Differential equation.

5. Always true. This equation is a variation of equation 4 solved for dv. Differential equation.

6. True if F and m are nearly constant during the change in time. Truly equal if F and m are actually constant. (HINT: So pick short Δt’s for good accuracy in numeric modeling.

7. Will be as accurate as Δv is.



10. True if v is nearly constant during the change in time. Truly equal if v is actually constant. (HINT: So pick short Δt’s for good accuracy in numeric modeling.

11. Will be as accurate as Δx is.

Equation AssumptionsAll approximation equations (3, 6, 7, 10, and 11) are only good estimators if the Δt is short enough so that the Δv and Δx do not change appreciably during the Δt..


32Product Specification Creation

Overview: The product specification describes all the necessary requirements of a product as well as the specific performance acceptability of each requirement. It is a specific type of goal statement that clearly and specifically lists the requirements. It should be made in table form.

Purpose:The purpose of creating a product specification is to clearly define the requirements of a final product. Both the engineers and the clients use the product specification to reach agreement about product expectations.

Who: While most engineering product designs begin with a starting point, the engineer needs to create an appropriate product specification. That is, a list of specifications that will create a high quality product.

When:Product specifications should be created when starting a product design. Creating a product specification is an iterative process that involves assessment by your client and/or boss. Product specifications are updated as understanding of the product grows or changes.

Why bother creating a product specification?1. It saves time! Creating a goal statement will keep you focused on your deliverables.2. Get alignment with your boss and client early. Everyone knows what is expected of the

product. There’s nothing worse than thinking you completed a product to find out you designed the wrong product.

3. A product specification provides the foundation for the prototype test plan.

How is a product specification created?Steps:

1. Create the Specification Table: a. Label column one “General Requirements.”b. Label column two “Specific Requirements.”c. Label column three “Acceptable Performance”

2. Fill out the Table: d. List the general requirementse. List the specific requirements for each general one.f. Assign a numeric value and unit of measure to each specific requirement for the product

to be acceptable.

Assessment CriteriaMuch like action items, product specifications need to be SMAR(T)Yes/No checklist for a product specification t:

Specific: The product specification is specific enough that everyone knows what the deliverables will be. The language is clear and concise.

Measurable: Each specific requirement has a measurable acceptable performance. Attainable: The product specifications are attainable. Results oriented: The product specification is a result, not a method.

*Example on next page Product Specification for a mouse death-trap:/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

33General Requirements Specific Requirements Acceptable PerformanceKill the mouse Mouse dies instantly Death<0.005 sec

Mouse is left in one piece One piece, no blood

Trigger

Trap must reliably trigger with a mouse

Trigger force < 5 grams

Trap must not trip if gently placed or slid

Trigger force> .05 grams

Usable

Trap may be set by a person with weak hands

< 150 gram required force on any moving parts

Bait must be common household item

Works with cheese or peanut butter

Dead mouse must be easy to remove

Place to release trap no matter where mouse is situated

Low-cost ManufacturingPiece part cost must be low <$.15Assembly cost must be low <$.10Packaging for sale must be low <$.03


34Professional Decision Making (PDM) Process

Overview: The PDM process is a proven strategy for solving a problem or completing a task. The PDM process is general enough to be used for any task, yet specific enough to guide you through the most difficult problems. There are 6 steps in the process: Define the Situation, Define the Goal, Generate Ideas, Create a Plan, Take Action, and Review.

Purpose:Most problems and tasks require the same steps to complete. Rather than try to figure out a different process to solve each new problem, professionals recognized that they could generate a general process they follow every time, no matter what the task. The PDM process steps through a solution path for any problem. Following it helps engineers get started, stay on the right track, get though obstacles, document the solution, and completely finish the problem.

Who: Individuals or entire teams can use the PDM for any problem.

When:The PDM process can be used for solving any problem or completing any task. It is more useful the more complicated the task, especially open ended problems. It can be used for: homework problems, engineering design, engineering analysis, long-term team project, product testing, even small tasks like purchasing a gasket, etc.

Why should I bother following the PDM process?1. Some problems are too complicated to solve without a process.2. Practicing the process on simple problems will make it easier to use for larger, more

complicated problems that you wouldn’t be able to solve without it.3. Following the PDM process prevents “hitting a wall.” If you have a process to follow you

won’t find yourself staring blankly at your paper.4. You can make the process work for you. You don’t always have to follow it exactly.

How do we implement the PDM process?Step 1: Define the Situation. Make a list of everything important to the problem.

1. What additional knowledge can you find? Ask questions, look up information, interview others, research background information.

2. Is there a conceptual representation of this situation? The important thing to do in this step is transfer the physical world problem into the conceptual world. This usually involves making assumptions about the real-world situation, so that an engineering math model represents the situation.

3. Can you draw a sketch that represents the situation? Drawing the situation usually helps to conceptualize the problem.

4. How is the present task related to other relevant factors? Consider factors such as people, the overall project, the organization.


35Step 2: Define the Goals. Make a clear statement of what problem(s) the solution should solve.

1. What are the real problems you need to solve? Consider all the problems and focus on the ones you need to solve. It is important to scope the goal so it is attainable in the time you have. Make sure you are listing goals not methods.

2. What will be your end results? Create a goal that clearly describes what your concrete deliverable will be when you are all finished.

3. What are the criteria? For longer projects, the goal should have a set of measurable criteria that your finished deliverable will meet. These should be challenging, but still attainable. Sometimes they are split up into “needs” and “wants.” The needs must be met and the wants should be met.

4. Is your goal SMART? Goals should meet the criteria for action items (see pg #): be Specific, Measurable, Attainable, Results oriented (not a method), and Time bound.

Step 3: Generate Ideas. You need lots of ideas on how to solve the problem. 1. What problems do you need to solve to reach your goal? Identify and prioritize the problems

that might prevent you from reaching your goal.2. What are alternative ways to solve the problems you now face? Write down many alternatives

for reaching the goal. There are many methods to come up with alternatives: Brainstorming (see “Brainstorming”), talking to others, researching previous solutions to similar problems.

3. What is the best way to reach your goal? Assess solution ideas and select the best idea or combination of ideas. There are many methods to make your decision (see “Decision-Making”): Engineering decision matrix, DFMA (Design failure mode analysis), team voting, etc.

Step 4: Plan a solution. Make a brief step-by-step outline of how you will get the solution. Don’t do the solution yet, but rather plan the solution.

1. What problems will you run into while your using the idea you chose? Identify and prioritize the problems that might prevent you from implementing your idea.

2. What steps will you take to overcome the problems you face? Write down the steps needed to reach your goal. Your documentation should be as short as possible to present all the essential details. Often the steps can be processes you already know. The GENI process (see pg #) is a simple way to plan a by-hand math modeling solution.

3. Have you thought of all the relevant details? Check your plan for missing details.4. Does the plan follow a logical order? Make sure your steps flow in order to use your time

most efficiently.

Step 5: Do the solution. OK, now that you know what you to do, do it!1. Are you following the plan? Make sure you are following the plan you made. Do process

checks at natural stopping points or when you think you are getting off track.2. Are you documenting your solution? Make sure you record your solution, so you don’t have to

do it again. Document any changes you make to your plan.

Step 6: Reflect on the solution. What can you learn from this solution to help you in the future?1. Was your goal reached? Make sure you reached your goal.2. How can you improve your future performance? Give yourself and/or ask for feedback:

Identify strengths, areas for improvement, and insights about your performance. Plan for improving your future performance.

Assessment CriteriaYes/No checklist PDM Documentation should have:/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

36 A specific title. All six steps, clearly labeled. Complete steps:

1. Situation: Concise list of all information provided, implied information, researched information, conceptual representation of real-world situation.

2. Goal: Primary goal, sub-goals, criteria (specifications and requirements).3. Ideas: Appropriate sized list of alternative ideas, best idea decision and rational.4. Plan: List of all the steps that were taken during the “Action” step, no missing details,

logical/efficient order.5. Action: Documentation of implementing the plan. Notes of insights, changes, and time

management of taking the action.6. Review: Design assessment (if the goal was reached and how to improve the results

next time), process feedback (how to improve performance). Clear and concise documentation. Organization and white space that makes it easy to read.


37 Project Notebooks

Overview: A project notebook is made by a team to present their results and processes. It usually contains copies of logbook pages, project timelines, goal statements, printouts of math models, research summaries, reports, etc.

Purpose:A project notebook is made by a team to present at a design show or design review to illustrate their progress or results on a long-term team project. It depicts the documentation of engineering results and processes of the project.

Who: Engineering teams keep project notebooks with contributions from all members.

When:A project notebook is started at the beginning of a project and is updated as the project progresses. Finalized documents should be added to the team notebook upon completion. Other documentation like logbook copies can be added at regular increments, after task completion, and shortly before design reviews or shows.

Why should we bother keeping a project notebook?1. A project notebook allows all the resources and results of a team to be easily accessible to all

team members at all times.2. Your client or boss will be able to easily view and understand the work you have done.3. A project notebook encourages producing presentable concrete deliverables at intermediate

stages of a project, so the team isn’t working extra hard at the end.

How is an excellent project notebook created?1. Buy a large enough 3-ring binder to fit all your documentation (oversizing is always better—

3”).2. Create sections with dividers for all your documentation: Timeline, team information, meeting

notes, research, design reports, progress reports, concept design, detail design, analysis, tests, manufacturing sketches, feedback, assessments, etc.

3. Add to it as you complete tasks. An action item is not complete until it is added to the project notebook. If you put off creating your project notebook until the last minute, you’ll be overwhelmed and rush too much.

4. Include all your significant documentation. Each project requires different content in the project notebook. Make sure all the information that the client or boss may want to see is readily available.

5. Make sure your notebook is well organized and easy to read. Remember that info your boss wanted needs to be readily available; that means he/she needs to be able to find it.

6. Create summaries, charts, and pictures—presentations and/or reviews are usually short. Consider these to be the “site map” for the notebook. You need to be able to explain what you have accomplished in as little time as possible. Sometimes the project notebook is handed off to your boss or someone else to continue the project. Nobody wants to wade through your entire notebook to understand what you accomplished and how you did it.


38Project Timeline Creation

Overview: A “project timeline” is a schedule line showing milestones, smaller tasks, and planned events in a project.

Purpose:A project timeline is a vital tool for planning and organizing a project, as well as keeping the project progressing. It breaks the project up into manageable pieces. It provides the specific dates to deliver concrete results at milestones.

Who: Engineering teams use project timelines for all long-term (more than 1 week) projects.

When:Project timelines are created at the very beginning of a project, and are revised as the project progresses. Usually major timeline revision and detail addition occurs after the team creates the goal statement/product specification. On large projects the goal statement may become part of the timeline.

Why create a project timeline?1. It saves time! Project timelines help the team focus time and efforts in the right places at the

right time, reducing time and effort by minimizing inefficient work.2. Keep the project on the right track. It is easy to get behind on long-term projects, but not if you

have a timeline to hold you accountable for completing deliverables.3. You can quickly see that everything in the plan will get done.

How is a project timeline created?1. There are several different software tools like Microsoft Project, excel, etc. which come in

handy for creating gantt charts, but it doesn’t really matter what you use—pen and paper work fine too (as long as you can read it).

2. Break the project into a few major phases. Each phase should conclude with a major deliverable (milestone), for example: “Proto 1 is complete” or “Final testing is complete.”

a. The following is an example of a general project outline:Goal Creation →

Product SpecPlan → Iteration 1 → Iteration 2 . . . → Report & Deliver

Results

Timelinecreation

→ Timeline Revision & Detail

Design → Build → Test →

Assess Redesign→ B, . . .

b. You can use this general outline as a guide to customize the timeline for your project. 3. Anchor the end of each phase with a date. No deadlines=no plan!4. Break each major phase into smaller tasks as necessary. Attach deadlines and owners (who

will do the work).5. Continue breaking the work down until it is clear who will do each part of the project by when.

Assign action items.6. Make sure the whole plan adds up to completing the project on time. (HINT: It’s usually a

good idea to “pad the schedule” by planning on completing the project ahead of time.


http://www.pmforum.org/library/glossary/PMG_E03.htm#Event

http://www.pmforum.org/library/glossary/PMG_P02.htm#Plan

http://www.pmforum.org/library/glossary/PMG_L02.htm#Line

39Timelines are frequently shown as Gant Charts:

Phase Task Owner 8/3 8/7 8/10 8/14 8/17 8/20

FinalizeConcept Design

Paper Concept Designs

AZ & BB

Assess Concepts AZ & BB

Peer Review of Concepts

Team

Team Design decision

Team

Detail Design

Detail Design CC

Assessment CriteriaYes/No checklist for a project timeline:

Phases will build to reach the goal. Phases have deadlines attached. Phases are further broken into smaller tasks as necessary. Plan is written down. Pieces of plan that can be done concurrently are shown concurrent and not one after the other.


40Prototype Testing ProcessOverview: A “prototype testing process” is a set method to plan, conduct, and report a test aimed at measuring how well your prototype performs compared to a set of product specifications.

Purpose:Testing prototypes is often the best way to assess a design. Too often qualitative tests are performed on a prototype from which design decisions are made, but no documentation or proof gets recorded for the design change. Following a process and planning a quantitative test to hold up against the product specifications, will result in clear, objective evidence to support design improvements and changes.

Who: All good Engineers use a testing process in order to measure the performance of a working prototype.

When:Follow this process after every completion of a working prototype.

Why should we follow a prototype testing process?1. It makes your testing plan and results obvious and clear to understand for your boss or clients.2. It provides objective numbers as reasoning for design decisions.3. It saves time. You could omit an important step like recording your data and have to redo it.

How is a high quality prototype test run?Rules:

1. Plan: Create a test plan before you start.a. Create the table below and fill out the first 3 columns based on the “product

specification” you created during the first phase of your project.b. Plan to take enough data to make sure that you are not drawing conclusions from results

that may be a measurement error.c. Create a procedure that lists the detailed steps for each measurement plan. Some may

be as simple as 4 steps. For example:Weight Measurement Procedure:

i. Turn on and tare digital scale.ii. Place prototype on scale, making sure there is no contact with anything nearby.

iii. Record the number with units.iv. If #’s are within .01 lbs, add the three recordings and divide by three.

Otherwise, repeat procedure until they are. On the other hand, they may be as complicated as 25 steps, especially for something as complex as an integrated launch test.

Product Specification

Acceptable Performance (#)

Measurement plan Result

Light-Weight Less than 2 lbs Three members take separate measurements. Take mean as long as the #’s are within 0.01 pounds.

2.4 lbs

Launch height 150 feet Launch rocket 3 times. Measure with tripods. Take lowest number as long as #’s are within 8 feet.

94 feet

etc.2. Document: ALWAYS document your test in your logbooks.

a. Include an experiment sketch.b. Record your data as you collect it in a clearly labeled and organized table (refer to the

criteria below)./tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

413. Collect objectively: Make sure your results aren’t skewed by your expectations.

a. If you have to, ask a friend or teammate to take the data while you record it.b. It’s also important to stay consistent in how the data is collected.c. Follow your test plan procedure and record any revisions during testing.

4. Analyze: Analyze the data.a. Usually the data should be entered in a spreadsheet and mathematical/graphical

operations performed.5. Interpret: Interpret the data in a report.

a. Scope the report to fit the importance of the test. It can be a half page to 10 pages.b. What does the data mean? How does it compare to the expectations (product

specifications)?c. Format the report to fit the criteria below.

Report Assessment CriteriaYes/No checklist Each experiment report should have:

1. Descriptive title of the test and the date.2. Test Plan and Results: Include the table you created in the test plan with the results column

filled out. Also include the procedure plan and any modifications made to it.3. Test description section: Brief description of how the data was collected. Include the test

sketch from a logbook as necessary.4. Analysis: Briefly describe the process you used to analyze the data and/or predict results (as

applicable). Attach appendices of calculations as necessary.5. Conclusions/Recommendations: Interpret what the data means and (if applicable) compare

the test results to mathematical predictions. For instance, in the example table above the weight was larger than the specification—Conclusion: Must reduce weight by more than 0.4 pounds.

Logbook Documentation Assessment CriteriaYes/No checklist Logbook documentation should have:

1. Descriptive title line of the test with date.2. Test sketch: Detailed sketch of the test including labels of all apparatuses.3. Test Plan: You should have the test plan table and procedure in front of you in your logbook

while you conduct the test.4. Data Collection Table: Make sure the table has a title, clearly labeled rows and columns, units,

and the correct resolution on measurements.


42Prototyping Sketches

Overview: “Prototyping Sketches” are simply hand drawings that engineers create to show parts in enough detail to fabricate them.

Purpose:It is important to sketch and dimension parts before building. Prototyping sketches are the fabrication plan. It is also important to have documentation of what you built (it’s size, shape, material), which a prototyping sketch provides. The documentation is used in case the prototype is lost or broken beyond repair, or if someone else wants to replicate your prototype, or if your boss/client wants to see a paper copy of what you built.

Who: Every good engineer defines the parts (visually with dimension) before spending time building them.

When:A prototyping sketch should be made every time before building a working prototype.

Why should I bother creating such a detailed sketch before I build?1. It saves time!2. Design bugs are discovered sooner.3. They help you plan your how to build your prototype.4. They are an excellent way to document your design process5. They are an easy way to keep track of improvements made in the product along the way.6. Prototyping sketches can be used to rebuild, build multiple identical models, contract someone

else to build for you.

How are excellent Prototyping Sketches created?1. Start by getting the design hashed out roughly with concept sketches.2. Create a list of requirements of the product, and list of how parts will work/fit together. 3. Use engineering paper, straight edges, and a good pen/pencil to draw exactly what you plan to

build. 4. Follow the criteria below.

Assessment CriteriaYes/No checklist For each prototyping sketch, you should:

Draw to scale. Show multiple views if necessary. Show small features in a (larger scale) detail view if necessary. Dimension all features. Call out tolerances. Call out materials. Someone unfamiliar with the design can explain the part to you from only looking at the

sketch.


43Statistics Overview: Engineers use statistics to analyze the data from experiments or design experiments. The following is an overview of statistics for the ordinary engineer.

Statistics NomenclatureThe following are the abbreviations that are commonly used statistics:

= Sample Mean (Measures the central tendency. Known as the “average” in layman’s terms)S2 = Sample Variance (Measures the “Dispersion”)S = Standard Deviation (Measures the “Dispersion”)m = Slope

Histogram = Visual representation of data distribution. Graph of frequency versus data range.Single Point Calibration = Linear model of behavior using only one data point.Linear Regression = Linear model of behavior by minimizing data point distance from a “best fit” line.

Statistics Equations

HistogramTo create a histogram, simply count the number of data points in each range. To decide what the ranges should be, divide the total range into 5-10 smaller ranges (usually takes some trial and error to figure out).Example:The following table shows the data values for a 40 trial test with a constant independent variable:

1.25 2.25 5.0 3.75 4.25 4.0 3.0 6.25 5.25 5.54.75 7.75 2.75 3.0 0.5 3.5 4.25 2.5 3.75 5.03.5 0.75 4.0 5.5 2.0 5.5 3.25 4.5 1.5 3.252.5 5.5 6.75 7.0 5.0 4.75 7.25 5.75 7.75 6.0

Each bar shows the number of times data points in that range appear. The distribution above is not a bell curve, nor does it seem to have any peaks.


44Other examples that do show patterns:

Single Point Calibration

Equations: Use:

When you want to find the slope of the line

When you wish to find the value of ya at a point xa.

Example:The following graph shows the single point calibration for a spring.


45 Finding the slope: Estimating ya when xa = 3:

This calibration shows the calculation of the slope, m to be 1.5. The point where the line crosses the x axis (where the force is zero) is the neutral (un-stretched) length of the spring. It assumes that the spring is linear. This can be put into the common spring equation:F(x)=k*Δx where the spring constant is k is the slope of the line, so for this spring k=1.5 N/cm. The force of the spring when its length is 3 cm was calculated to be 3 Newtons.

Linear RegressionLinear regression can be done by hand, but it is slow and easy to make a mistake. Engineers typically use EXCEL or another software tool to do them now.Assumptions:

1. x is accurate or reliable2. Variability is in y

Example:The following graph shows the linear regression for a spring performed in excel.

A polynomial trend line of order 1 is a linear regression.The R2 value is an indication of the variability of the data points from the best fit line (how well the line represents the data). The closer to 1 the R2 value is, the closer the trendline is to the data.In order to increase the significant digits for a trendline equation, double click on the equation and change the number of decimal places under the number tab.


46Team Feedback

Overview: “Team feedback” refers to how well the team “runs plays”. Engineering teams use processes for all of their work. The processes are essentially the same as “plays” on the sports field. So when we give team feedback we assess how well we ran the play. Did we use the right process? Did we spend the right amount of time on the process? Etc.

Purpose:Feedback is always given with the intent of helping the team to improve its future performance. The feedback is not about the past—what the team did or failed to do—but rather about what they can do in the future.

What type feedback should be given?You should give your team feedback on its strengths, its areas for improvement, and insights into its performance using processes that the team would probably not notice without taking time to think about it. Feedback about strengths should be given more frequently than feedback about weaknesses and other insights, so the morale of team stays positive.

Who: Every good engineer participates in team feedback with their team and seeks feedback from outside observers.

When:Team feedback should be given routinely, rather than being “saved up.” Common times to give feedback are at the completion of tasks, at the end of every meeting, and at regularly scheduled checkpoints.

Why should I take the risk of giving feedback?1. You can prevent small problems from growing into HUGE problems by resolving performance

issues as they arise.2. You can improve team processes and how well you use them for high team performance early

and throughout project.3. You can grow team performance by identifying process strengths.

How is excellent team feedback constructed?Questions to guide you through team performance feedback:

1. Did we use a process? Was it the best choice?2. How well did we use the process? Did we skip a step or get off track?3. How well did everyone understand the process being used? Were there various ideas of what

the process was?4. How well did everyone buy into the process? Was the process used by consensus?5. How well did the various roles people adopted work together? Were they synergistic or out-of-

sync? What does an excellent engineering team do with feedback?

1. Take good notes in their logbooks.2. Make a specific plans of how to improve their performance based on the feedback.

Assessment Criteria-3: Detrimental to team/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

471: Beginning level Engineer 3: Working level Engineer 5: “Expert” level Engineer

Attribute -3 1 2 3 4 5Team

Process Focused

Feedback blames specific people for poor performance.

Feedback does not mention which process was used.

Feedback mentions which process but not how well it worked.

Feedback focuses on processes the entire team used.

Addressed Teamwork

Feedback points out an individual for not “working well with others”

Feedback only mentions teamwork or consensus, not both.

Feedback only briefly mentions teamwork or consensus.

Feedback states how well the team worked together and weather there was consensus.

Team needs/goals

Focused

The feedback does not focus on something the team can improve to better meet its goals.

The feedback is only aimed at helping the team meet its secondary goals.

The feedback is aimed at helping the team meet its primary (and secondary) goals.

SpecificFeedback is vague or general

Feedback clearly states specific actions

Feedback notes specific details of action

Forward Focused

Feedback is negative.

Feedback does not mention how to improve

Feedback gives vague ideas of how to improve

Feedback has a clear improvement plan

Rationale Feedback gives rationale that is wrong or blaming.

Feedback does not mention why the action helped or impaired team performance

Feedback hints at why the action helped or impaired team performance

Feedback clearly states why the process helped or impaired team performance

Distribution One or two team member(s) dominate the discussion

Some team members do not give feedback.

All team members give some feedback.

All team members give equal amount of feedback.

ScopeThere was too little or too much information to take the team to the next step.

The team can use the amount of information presented.

The team can most efficiently use the amount of information presented.


48Team Lifecycle

Overview: High performance teams have gone through the following phases of team formation:

Forming

→

Storming

→ Norming

→ Performing

The number 1 cause for low team performance is failure to move though Storming to Norming.

Who: Most teams go through a team lifecycle, although some do not reach all the stages.

When:The a team can move through the steps of the team lifecycle as fast as a few weeks and as long as never reaching the “performing” stage. Team formation is not necessarily linear. Often times, teams start to reach the storming stage and avoid conflicts by going back to the forming stage rather than surfacing conflicts and working through them.

What do these stages mean?Forming:In the Forming stage team members are just getting involved in the new experience of working together as a team. Typically they may experience the following feelings:

1. Suspicion, fear and anxiety about being part of a new team and any potential time and work commitments that may come out of it

2. Confusion about the reasons for the team and expectations 3. Excitement about being part of a new team 4. Pride in being a part of a new team

Storming:After getting over the initial feelings of being part of a new team the storming begins. This can be a difficult stage in team development that may include arguing among members, defensiveness, competition, the development of factions in the team, chasing the task at hand, disunity, mistrust, jealousy, and political infighting. Typically team members may experience the following feelings:

1. Dramatic ups and downs in attitude and expectations for the team 2. Resistance to the methods used by the team 3. Resentment over the selection of tasks and roles


494. Confusion over how to progress, and how to work with each other 5. Frustration over individual weaknesses

Norming:After the storming has begun to settle down, the team enters a period where they begin to reconcile the roles and expectations. Ground rules emerge and are adhered to. Some progress may become apparent. Typically the feelings team members experience through this norming stage of team development include:

1. The development of a common set of goals and interests 2. Acceptance of other team members and each person’s role 3. A sense of relief that perhaps the team may achieve success 4. Team spirit, an attachment to the group develops


50Performing:The norming process leads to the final stage of a team’s development, performing. At this stage team members are open to constructive self-evaluation and change. The ability to constructively work through issues and group problems quickly is achieved. Communication, trust, and the willingness to rely on other team members have been developed. Typically team members may experience the following feelings when the team reaches the performing stage:

1. Comfort working with the team 2. Satisfaction with the team process and progress 3. An understanding and appreciation of the other team members strengths and weaknesses 4. Loyalty to the team 5. Use of individual strengths

Once a team reaches the performing stage the results can be phenomenal. A good coach and good facilitation of team activities combined with training can help speed the team through development to the performing stage.

How can we help the team reach the “performing” stage faster?Tips:

1. Get to know each other: Take an interest in your teammates’ welfare.2. Use feedback early and often in order to surface concerns and team dynamic problems before

they grow into major problems.3. Bring conflicts and frustrations to the team in a professional manner at appropriate times

(feedback sessions).4. Make solving the conflict and frustrations the team’s problem—not merely the individual’s

problem.5. Focus on utilizing each members’ strength’s in meaningful ways on the tasks.6. Playing favorites is obviously counterproductive.


51Team Meeting Process

Overview: A “Team Meeting Process” is a simple process all teams can follow to run an efficient meeting. The main goal of team meetings is to move the project to the next steps. This is done by team members updating progress and planning the next steps using action items.

Purpose:The goal of team meetings is to update the team on the project progress and make team decisions. Following a meeting process helps them run more efficiently. Team meetings are an important part of all team projects, but if you don’t have an efficient process to follow, they can “suck up” too much time.

Who: Engineering teams use a team meeting process to keep their meetings effective, efficient, and thorough.

When:Team meetings are scheduled at time intervals long enough to match the time it takes for the team to complete their action items or make enough progress that they need team feedback on the direction they should go next. They also have to be scheduled at short enough intervals that all the team members are aware of what the others are doing.

Why should we bother using a meeting process?1. It saves time!2. Unstructured meetings can take 2-3 times longer than a structured meeting and get less done.3. Regular meetings help speed up the progress of the project.

How do you run an excellent team meeting?Rules:

1. One team member records meeting minutes for the project notebook.2. All team members record meeting notes in their logbooks, especially their action item list.3. Create and follow the Agenda.

a. Do process checks (as necessary) to redirect the team to the agenda item or move on if you go over time on an item.

4. Always do at least one feedback session at the end of the meeting (it doesn’t have to be long).

* Steps on next page.


52Steps:

1. Create and/or review the meeting agenda. It’s a good idea to write the agenda on a large board or for everyone to have a paper copy.

a. Example: Item Goal 1. AI Update (10 min) Everyone aware of progress.2. Decide best concept (25 min) All participate and agree on best concept design 3. Assign AI’s (10min) Move project to next steps, all have tasks.4. Individual Feedback (10min) Improve ind. perf. on project, all get feedback5. Meeting Feedback (5 min) Improve meeting efficiency and facilitation

2. Report on progress of each team member’s action items.3. Do other agenda topics.4. Discuss progress on the project based on where you are in your project timeline and what work

the team needs to get done by next meeting. 5. Create action items to get there. 6. Give individual or team feedback (focused on project performance).7. Give meeting feedback (focused on this meeting).

b. Meeting feedback can be much shorter than performance-based feedback.c. It can simply be, “Does anyone have any feedback on the meeting?” “Sarah, what do

you think a strength of this meeting was?” “Jim, how do you think the meeting could be run more efficiently next time?”

*Refer to the “Action Items” Resource for how to use action items.


53 TutorialsLinear Algebra-by hand Tutorial 1

For this tutorial use the following matrixes:Be sure to show all work, do not use Matlab.

Skill 1—Matrix addition/subtraction with other matrixesIn order to add (or subtract) two matrixes together, they must be the same size (same number of rows and columns). To add B to A you add the number in the first row, first column of B ( B11 ) to the number in A11, B12 + A12, and so on.Example 1.1

1. Write c+d in the space below.

Skill 2—Matrix multiplication with scalarsTo multiply a matrix by a scalar, multiply the scalar by each space in the matrix.Example 2.1

1. Write 2*e in the space below. Skill 3—Matrix multiplication with matrixesIn order to multiply two matrixes together they must be compatible. If you are multiplying matrix P(pr,pc) and matrix Q(qr,qc) then pc=qr in order for the two matrixes to be compatible. The resulting matrix will have the form of R(pr,qc). To multiply A by e, multiply A11 by e11, then add that product to the product (A12*e21), then add the sum of the products to another product (A13*e31). That sum will be the value in the first row of the resulting vector. If that is confusing, don’t worry, refer to the example. Note: You can not divide a matrix by a matrix, but you can divide a matrix by a scalar using matrix multiplication rules.Example 3.1

1. Write e*c in the space below.

2. Write c*e in the space below.


54

Skill 4—Identifying an identity matrixAn identity matrix is the algebra equivalent to 1. An Identity matrix consists of a square matrix with a diagonal of ones and the rest of the matrix filled with zeros. Ni j=1 when i=j, Ni j=0 in all other cases.

Example 4.1

1. Write a 3x3 identity matrix in the space below.

2. Multiply your identity matrix by A in the space below.

Skill 5—Identifying symmetry in matrixes

In order for a matrix to be symmetric Ni,j=Nj,i , for i is not equal to j.Example 5.1

Symmetric :

Not Symmetric:

1. Write a 2 by 2 matrix that is symmetric in the space below.

Skill 6—Transposing a matrixTo transpose a matrix Fi,j Gj,i (rows become columns, columns become rows for every space in matrix)

Example 6.1

fT=

1. Write the transpose of e in the space below.

Skill 7—Converting a system of equations to matrix form (linear algebra form)Engineers use linear algebra to solve high order systems of equations by converting equations to matrixes and using linear algebra to solve. Use what you have learned about matrix multiplication to multiply A by a variable matrix X in the space below. Then set the product equal to the e vector.

1. Multiply A by X in the space below.


55

A*X =

2. Convert the following systems of equations to matrix form in the space below.

Ax+By+Cz=QDx+Ey+Fz=RGx+Hy+Iz=S

3. Take a minute to check your answer from the last problem. Check to see if figure 7.1 matches the solution that you came up with (if it doesn’t try to figure out what is going on).

Figure 7.1

4. Write the system of equations (not matrixes) that resulted from problem 1 (in Skill 6) below:

5. Write the following system of equations in linear algebra form (matrix form) in the space below.

2a+4b+6c=4a+b+c=14a+2b-8c=9

Skill 8—Calculating determinantsIn order to take calculate a determinant you must have a square matrix. The I I symbol is used to indicates a determinant. It is easier to show you how to calculate a determinant through example than to try to explain it.

Example 8.1

Example 8.2


56

1. Calculate the determinant of B in the space below (be sure to show all work).

Skill 9—Using forward elimination, backward substitution to solve a system of equationsUsing forward elimination and backward substitution is the way in which you can solve a system of equations without a calculator or a computer. In the end you want your system of equations to look something like this:

Notice the bottom half of the matrix is filled with zeros

In order to get a system of equations into this form you simply use algebra to cancel variables until you solve for one. Then you substitute the known variable back into one of your other equations until you find all of the variables you are looking for.

Example 9.1

(1) a+b+c=3(2) 2a-b+c=4(3) –a+2b+2c=2

get rid of variable a

(1) a+ b + c = 3(3) –a+2b+2c = 2 (4) 3b+3c = 5

-2*(1) -2a-2b-2c=-6(2) 2a -b +c= 4 (5) -3b-c= -2

get rid of variable b (4) 3b+3c = 5(6) -3b- c = -2 (7) 2c = 3

Now we can write equations (1) , (4), and (7) in linear algebra form.

Notice the bottom half of the matrix is filled with zeros


57Now we solve for c

2c=3 ; c= 3/2

Now substitute c into (4) to get b

3b+3(3/2) = 5 ; b=1/6

Now substitute c and b into (1) to get a

a+(1/6)+(3/2)=3 ; a=4/3

1. Solve the following systems of equations using forward elimination, backward substitution. Show the matrix form with the lower half equal to zero and then solve for the variables in the space below.

a – b = 1-a + 3b = 3

Note: You should be able to solve up to a 3rd order system of equations by hand using forward elimination, backward substitution.

Excel: Professionally formatting the output Tutorial 2

Skill 1—Reasons for professionally formatting the outputExcel can be a great tool for both students and engineers. It allows the user to record data, make calculations and put the data into graphics such as charts and tables that are easy to understand and interpret. However, it is just as easy to misuse spreadsheets by making them sloppy and confusing. Skill 2—Recording data and making calculations/tt/file_convert/5acca81f7f8b9a875a8cdfcd/document.doc

581. Label the columns with simple names so that when you are recording you don’t get confused

about things like which column was the x-axis and which was the y-axis.2. When you are first recording the data and making calculations, don’t worry about the way the

spreadsheet looks. Most likely you will make a lot of changes and if you are altering the appearance every time you move a column or chart, you will waste some time.

Skill 3—Making the output look professionalOnce you get done entering the data and making calculations you can then start to think about how you are going to present the data. For this class most of the time (not all of the time) we will be using a scatter plot with a trendline, but this is not the only thing that excel can do, try looking at the other types of graphs and think of when they might be useful. Note: I am assuming that most of you have used excel in the past and know how to create simple graphs and format tables. If you need help ask a classmate or try using the help tab in excel.

1. Download the spreadsheet for tutorial 2 from________________________.2. Look at the document in both normal view (the view you see when you open the document)

and print preview. List 3-5 things about the spreadsheet that looks confusing or sloppy. ____________________________________________________________________________

3. Fix the spreadsheet the best you can so that the graph and table look professional. Look at the print preview to make sure it will also look good when printed. Hint: I haven’t given you any information about what the data is, so just make up titles. Don’t worry if it makes sense.

4. Once you have fixed everything that you can think of, look at the next sheet tab labeled ‘Professional’ at the bottom of the work area. Compare the two sheets. List any differences (including improvements) ________________________________________________________________

5. Change your sheet to match all of the strengths listed in the ‘professional’ sheet and in Skill 4 below. If you need help look at the next page.

Skill 4—Things that make a spreadsheet look professional1. Simple but clear titles on all tables, columns, graphs, axis, legends and the spreadsheet itself.

Be sure to include units if needed. Bold font and color codes can be useful but be careful, too much can be overwhelming.

2. Make the spreadsheet so that even a person with no technical knowledge of the subject would be able to understand it.

3. It is ok to have white space; if you fill the whole spreadsheet with data it can become cluttered.4. Be sure to include things like the people who made the spreadsheet, the date, the assignment

and any other relevant information.5. Use borders around data in order to make it clear what numbers are in what columns. You can

also make the borders bold around titles to help bring them out. It is possible to overuse borders, so only use them when it is necessary.

6. When in doubt keep it simple!

Skill 5—How to format tables in ExcelHere are a few hints to help you get from novice to professional.

1. Figure out where you are going to put everything, sometimes your tables are going to be very long and have to stretch for pages, in that case you will most likely need to put the graph on the side of the table instead of the bottom. Either way size and position both the graph and table accordingly.

2. To insert rows or columns: right click on either a number (for rows) or a letter (for columns) where you want to insert the new space and then click Insert. I always like to insert a column


59and row at the top and left side of the page just to give myself some room to work and to help center things when finished. This is also how you make room for your name and title etc…

3. Notice the main title for the spreadsheet and how the cell it is in is larger than the other cells. This is because it has been “merged”. To merge cells: Highlight the cells you want to merge and then right click. Select Format cells (this is the command center for nearly all of the table functions, in order to make professional documents you must go through each tab and play around) then select the Alignment tab and finally click the box next to merge cells near the bottom.

4. Also in the Alignment tab in the Format cells window is the alignment for text and numbers. Make sure that your titles and your data have the same horizontal alignment. See the novice sheet for an example of the wrong way, and the professional sheet for a good example.

Skill 6—How to format graphs in ExcelGraphs can be kind of tricky, there are certain commands in places that you wouldn’t naturally expect them to be. In general, first try right clicking directly on the item that you want to change, if that doesn’t work look at some of these basic hints.

1. To change the titles for the data in the legend from Series 1 etc… to something else: right click anywhere in the chart area. Select Source Data then select the Series tab in the window. You can now select the series you want to rename and type the new name in the space labeled “Name”.

2. To add a trendline: right click on one of the data points then select Add Trendline. Play around in this window until you figure everything out. If you want to change the trendline later: right click on the trendline then select Format Trendline. Hint: This is where you can change the name of the trendline in the legend.

3. To format the axis: right click either on the axis itself or one of the numbers that labels the axis. Click on Format Axis, again play around in this window until you figure everything out. Notice how the y-axis in the novice sheet goes down to –5 but the lowest data point is at 0. Change the minimum value from –5 to 0.Note: You have to format the x and y-axis separately.

4. To add or change titles: right click in the chart area and select Chart Options. Click on the Titles tab and edit the titles on the graph. While you’re here take a look at some of the other things you can do in this window.

5. To change the colors, or shapes of anything: right click on the item you want to change and then select Format … This should open a window that you can play around with to customize your graphs. Try right clicking directly on the pink data points and change the color to dark red. Then change the color of the trendline to light red and the thickness of the line. You can do this for everything including the titles, and the axis. You can also change the color of the default gray background to white if you prefer.

General Tip: The best way to learn excel is to play around in the windows and try to figure out what everything does and make mental notes of where you can find tools and format options.


60

Insert Excel Page here


61

Web Page: Building your first web site Tutorial 3

Skill 1—How to create a public folder on your H:\ drive1. First you need to set up your H:\public_html directory with the correct read/write permissions. Go

to the ITS help page at www.helpdesk.uidaho.edu. Follow links FAQ “how do I create my personal web page?” Follow the instructions there. If everything works you should have a H:\public_html folder when you finish.

Skill 2—How to make a web page in Word1. All of the files for your site need to be stored in your H:\folder. In this folder you may simply put

all your files (if your web stuff is small) or you may put sub-folders inside the main folder to help organize files (if your web stuff gets complicated). Make sure your file and folder names do not contain any spaces in them.

2. Open MSWord. Start a new Word document using "file" "new" "web pages" "blank web page". You will create your web page in MSWord.Note: Another option is to use “wizard”, just hit “wizard” instead of “blank web page”

3. You can now start putting things into the Word Document that will appear on your home page. Try starting with your home page. Type something like, "Electric Bill's Home Page," across the top. You can change the font style and size to your preference. Notice that Word has a little different look to it when editing a web page.

4. Now store the home page. Store your home page with the filename "index". This is very important!!! The web browser hunts for a file named "index" as the first page to display. Make sure you are storing into the H:\public_html folder and that your files are HTML type files when you save them. Also make sure you "store" before you go too far in creating the page.

5. Leaving your home page active on Word, create a second page. This will be the page you will jump to when you click on a hyperlink on the home page. Give a title to this new page like, "fun facts about the most important person in the world, ME!" You can then tell the whole world all about yourself…. Now store this page with an appropriate file name such as "funfacts". Make sure you store it as an HTML document in the right folder. CAUTION: make sure the file name has no spaces in it--sometimes space in file names make the hyperlink editor fail.

Skill 2—How to create a hyperlink1. Now you have 2 pages stored. The home page and the second page. Let's add a link from the

home page to the second page. On the home page type in something like, "Fun Facts about Yours Truly." Highlight the text you want to turn into a hyperlink. Turn it into a hyperlink by "Insert" "Hyperlink". Put the full path name of the second page you want to jump to in the top box in the "insert hyperlink" box. You may find it easier to use the "Browse" button to find it. Click OK.

2. By now you will notice that the words you highlighted are a hyperlink. If you click on it "VIOLA" (that's how WahLah is spelled in French…) MSWord jumps to the other page. COOL!

3. Now add a link on the second page to take you back to your home page. Do the same routine. Type in something like, "RETURN ME TO MY HOMEPAGE, I’m HOMESICK," and turn it into a hyperlink.

4. If you start Internet Explorer and open your home page (remember you named it index), it will let you click around using the hyperlinks.


http://www.helpdesk.uidaho.edu/

62

Owner of the web site: ________________ Person assessing: ________________Read each skill carefully, then rate the site based on the suggested items listed in each section. Make comments on why you chose to rank the site how you did.

Skill 1—Organizing your web site1. Does the web site have a theme? If all of the pages look good by themselves, that doesn’t mean

the whole web site will look good together. Themes connect your pages and help people get to know you better. A theme can be anything from an organized color scheme, a symbol (like a sorority or fraternity symbol) at the top of each page, or an organized structure for your hyperlinks. These things can help make your web page look professional and even help people navigate better.

2. Try going to a few of your favorite web sites and observe how they organize their site. What do you like and dislike about the way they organize their site? What do they do to make the site look good? What doesn’t look so good? Try to use some ideas from professional web sites to make your site look better and more organized.

Tip: You can use tables to make lists of hyperlinks in nice columns. You can change the fill color on tables to make them nicer. You can also hide the gridlines so the words are not in boxes.

Assess your web site’s overall organization by considering: theme, structure, usability, consistency and imagination.

Performance Level Low Medium HighRanking 1 2 3 4 5

Comments: _________________________________________________________________________

Skill 2—Writing content for your web site1. Is the web site interesting interesting? Think about the people that will be going to this site and

try to design the content for them. If you want to use it for school you could put all of the engineering projects you have completed and the things that you learned from each project. Maybe when you are looking for a job you could use the site to show your potential employer how great you are.

2. Does the web site reflect the designer? It is sometimes a good idea to put a few interesting things about you, like accomplishments and interests. This helps readers get to know you better (if that’s what you want).

Assess your web site’s overall content by considering: if the information is relevant to the site, insightful, personal, and interesting.


Comments: _________________________________________________________________________


Web Page: Improving and assessing your web site Tutorial 4

63Skill 3—Using links in your web site

1. Are the links in the website helpful? It might be a good idea to make a set of links to all of the main pages and put them at the top, side or bottom of every page to help people navigate.

2. Does the web site have links to other web pages? Don’t be afraid to put links to your favorite pages in your web site. Links are another way to help people see what kind of things you like.

3. Does the site have links imbedded in images?4. Does the site have links to download files like pictures or a resume?5. Do the links match the theme?

Assess the links in the web site by considering: relationship to theme, if they are all functional, have downloadable files, and if they are embedded in text and images.


Comments: _________________________________________________________________________

Skill 4—Using Graphics in your web site1. Are the graphics high quality? It is a good thing to have high quality pictures that the reader

can see clearly, but be careful because if they are too high quality the load time on your site will be slow.

2. Do the graphics help the theme? Use pictures that are relevant to the web site. Tip: You can change the background color and texture by "Format" "Background".Note: It is ok to take graphics from other web sites as long as you don’t claim that they are yours.

Assess the graphics in the web site by considering: resolution, page load time, backgrounds, and relevancy.


Comments: _________________________________________________________________________

Three greatest strengths of the site and why each is valuable:1. _________________________________________________________________2. _________________________________________________________________3. _________________________________________________________________

Three areas of improvement with an explanation of how to remedy or implement:1. _________________________________________________________________2. _________________________________________________________________3. _________________________________________________________________


64

Matlab: Equations in the command window Tutorial 5

Skill 1—Using the reference book. Matlab: An Introduction With Applications by Amos Gilat is a reference book for using Matlab. It does not read like a novel (thank goodness)! If you try to read it like a novel, you will remember very little and waste a lot of time. Your first skill is to adopt an effective strategy for using a reference book (engineers use a lot of reference books, so this is a useful skill). Here’s one way to approach a reference:

1. Treat the reference book like a dictionary. Few people read a dictionary cover to cover. Rather we look up a word when we need to know what it means.

2. How do you look up information in a reference? A dictionary is alphabetical, by the Matlab reference isn’t. So your first step will be to make a mental map of the reference. We’ll start with chapter one.

3. Spend five minutes figuring out what is in chapter 1. 4. Note to yourself what type of information is in the chapter. In this case, what basic information

about Matlab is in this chapter? You may want to highlight or underline big concepts. 5. As a trial run, look at the Table 1-2: Display Formats on page 12.

What do the commands in the table do? __________________________________________When would you want to use one? ______________________________________________Where do you find the correct syntax for these commands? ____(in this table, of course!)___

6. When you need to know the details of a command, you look it up. This sort of stuff is really hard to remember by simply reading. In ME223 you will always be allowed to use your Matlab reference book.

7. In the future, use your Matlab reference in this way.

Skill 2: Running Matlab like a calculator.You need to be able to convert mathematical equations into Matlab statements. If you work with a partner, test each other to make sure you both can convert an equation into a Matlab statement correctly.

1. Scan chapter 1 and become familiar with the basic type of information that is in it. (You may find the table of contents helpful to read.)

2. Start Matlab on a campus computer.3. Try problems 3a, 4a, 6a, and 6b using Matlab. Jot down the answers you get.4. Verify with a calculator that your Matlab answers are correct.5. Now try problem 16. Use equations with the variable names to get the answers.

Productivity Hint: Typing equations takes a lot of time. Sometimes you can type one in with one mistake and then of course it doesn’t do what you want. I think the “up arrow” key (or one like it) will retrieve a previously typed entry, which you can then modify (correct) before hitting “enter”.


65

Matlab: Writing and running a simple program Tutorial 6

Skill 1—Writing and storing a simple program.1. Programs files are called “script” files or “m” files in Matlab. Find the location in the reference

book about writing and storing script files.2. Scan the sections in the reference concerning writing and storing script files.3. Create a script file with the following commands:

% Any line that begins with a “%” sign is a comment. The program ignores this% type of line. The information is for the programmer, not the computer.clclines = input('How many times should I print the message on the screen? ');for N = 1:1:linesdisp('Steven Zemke eats worms!')end

4. Save this program in your own directory with a name you choose Caution: You can’t run the file if it has spaces in the title.

5. Close the editor window and re-open the program to make sure you can find it.

Skill 2—Running a simple program.1. Scan the sections in the reference concerning running a program. Re-open the program in the

editor-debugger window.2. Run the program by typing in the program name in the command window.

What did it do? _______________________________________________________________3. Answer the question in the command window with some small number, then hit enter. What

did it do? ____________________________________________________________________4. Run the program by using the “run” icon (the one with a piece of paper and an arrow pointed

down) in the editor/debugger window. What did it do? ________________________________Note: When you use the “run” icon it saves the changes you have made before running the program, otherwise you must save the program before you type the name of the program into the command window every time you make a change. If you don’t the program won’t recognize your changes and you will keep looking for errors you already fixed.

Skill 3—Edit the simple program.

1. Re-open the program in the editor-debugger window.2. Change the message in the display command.3. Re-save the program.4. Run the program. What did it do? _________________________________________________

Skill 4—Find out what the clc command does.1. Find clc in the index and find out what the command does.2. Why is it a good idea to start a program with the clc command? _________________________


66

Matlab: Program loops, number 1 Tutorial 7

Skill 1—Reason for using a loopLoop commands make the program execute several lines of code as many times as the programmer asks. One of the early tutorials had a loop that repeated the display command to write, “Steve Zemke eats worms” on the screen several times. You could fill pages with that wise message, but only need to write it out once in the code. Such power!Skill 2—Examine the syntax of the for-end loop command

1. Spend five minutes and scan the reference book on for-end loop commands.2. Examine carefully the structure of a for-end loop as shown in figure 7-5.3. If I have the following command:

for Counter = 1:2:7 end

a. What is the value of ‘Counter’ the 1st time the program hits this command? _________b. What is the value of ‘Counter’ the 2nd time the program hits this command? _________c. What is the value of ‘Counter’ the last time the program hits this command? _________d. How many times will the program loop through the commands in this loop? _________

4. Here’s a more interesting example: for Go_down = 1:-1:N end

a. What is the value of ‘Go_down’ the 1st time the program hits this command? ________b. What is the value of ‘Go_down’ the 2nd time the program hits this command? ________c. What is the value of ‘Go_down’ the last time the program hits this command? _______d. How many times will the program loop through the commands in this loop? _________

Note: Any of the three numbers after the equal sign can be variables.Skill 3—Play with another simple program using loops

1. Enter the following short program in the editor/debugger window. Save it with a file name of your choice (remember, no spaces).

clc% I will start by defining values for A and BA = 0;B = 4;% I will now run a for-end loop which will change the value of Afor C = 1:1:B;A = A + C;ABC=[ A,B,C]; %this will create an 1 by 3 matrix with A, B and Cdisp(' ') % This will create a blank line on the screen

% Hint: there must be a space between the quotesdisp(ABC) % This will display an array(matrix) with A, B, and C every time

% through the loopenddisp(' ')disp('The program is done')

2. Run the program once.3. Spend no more than 10 minutes comparing the code to the output on the screen to see if the

program did what it should have. If you can’t get it figured out in 10 minutes, don’t worry, the next tutorial will help you walk through the code to make sure the code is doing what it should.


67

Matlab: Debugging a program by “walk-through” Tutorial 8

Skill 1—How to “walk-through” codeDebugging by “walk-through” is a simple way to find errors in a program. It is also an easy way to analyze what some code is doing. The steps to do a walk-through are as follows:

1. Have a copy of the code on paper.2. Starting with the first command, jot down what it does.3. Move to the next command and jot down what it does, etc.

On the next page is a table with the code from the previous tutorial in the left-hand column (I’ve removed the comment lines to make it fit easier in the table). Instructions for the table are below.

Box 1: We will work through the boxes in the table from top to bottom. We will start in the column on the left, in the box marked “1.” When the computer executes the clc command, it clears the screen. The program moves to the next line.Box 2: When the program executes the A = 0; command, variable A is set to a value of 0 (Duh!). The semicolon stops the program from printing A = 0 on the screen.Box 3: You fill in box 3.Box 4: This is the first time the for C = 1:1:B; command has been executed, so variable C is set to a value of 1.Box 5: This is tricky and neat! The command A = A + C; can be read this way, “The new value of A equals the old value of A plus the value of C. Boxes 6-25: Read what’s in the boxes, or fill in what should be there. Go ahead and use fewer words than I did.

Skill 2—When to use a walk-through1. When you write a confusing piece of code to make sure it does what you want.2. When a piece of code is giving unexpected results.3. When you want to understand what a piece of code is doing (like examples in the book or in

later tutorials or code a teammate wrote).


68

Table 1-How to “walk-through” code

Command 1st time through the loop

2nd time through the loop

3rd time through the loop

4th time through the loop

clc 1 Clears the screen

11 Program does not come back here again!

A = 0; 2 Sets A = 0

B = 4; 3

for C = 1:1:B;

4 Sets C = 1 12 Sets C = 2 19 26

A = A + C; 5 Sets A = 1 13 Sets A = 3 20 27

ABC=[A,B,C] 6Sets ABC= a 1 by 3 matrix with the variables A,B and C

14 21 28

disp(‘ ‘) 7 Writes a blank line on the display

15 22 29

disp(ABC) 8 Writes the array [ A B C] on the display, ( 1 4 1)

16 23 30

end 9 Transfers control back to the for command

17 24 31 Transfers control to the next command

disp(‘ ‘) 10 Program does not come here yet

18 25 32

disp(‘The program is done’)

33


69Matlab: Input and display commands Tutorial 9

Skill 1—Correct syntax for input commands.1. Read about input commands.2. We will be using input commands for assigning numerical variable values, not for inputting

text strings.3. Type Z=input(‘Enter the value for Z ‘) into the command window. What did the computer

do?4. Answer the request in the command window by typing in a value for Z.5. Test what the value of Z is by typing in Z in the command window. What did the

computer do?

Skill 2—Correct syntax for display commands.1. Read about display commands.2. What two types of things can the display command display in the command window? _______3. How do you format a display command to put a verbal message on the screen? Try the

command out in the command window. (By the way, if you don’t realize it, any command typed into the command window, followed by an “enter” will be executed immediately. So you can try out any command in the command window. Try this out by typing clc into the command window followed by an “enter”.) _________________________________________

4. How do you format a display command to display a value of a variable on the screen? _______

Skill 3—Write a short program using the input command.1. Start a new script file in editor-debugger window. Your program will have 5 lines.2. In the 1st line ask the user (using an input command) to enter a value for variable A.3. In the 2nd line ask the user (using another input command) to enter a value for variable B.4. In the 3rd line ask the user (using another input command) to enter a value for variable C.5. In the 4th line write an equation to calculate the value of the average of A, B, and C. The

equation should look like:Average = (A + ……

6. In the 5th line display the value of ‘Average’ with a display command.7. Save the program with some name.8. Run the program. What did it do? ________________________________________________9. Run the program again and again. What does the command window look like? ____________

Skill 4—Improve the program.1. Your command window probably has a lot of clutter on it after you ran the program a few

times. Let’s fix that mess. First, insert a command to clear the command window before the first input command. If you can’t remember, this command was in tutorial 5.

2. Save and run the program a few times. Is the clutter better? Is the clutter completely gone?3. Read about the use of a semicolon (;) to further reduce clutter on the screen. You can find this

in the index to the book. 4. Make the program output as clutter free in the command window as possible.


70

Matlab: fprintf commands Tutorial 10

Reason for fprintf commandsIn the last 2 tutorials you used a display statement. The display statement lets you output a pre-set message or a variable value to the screen very easily. However, the display statement won’t let you mix text and variable values. For example you may want to have this message appear on the screen:

“There are 5 springs in the sample and the average length is 2.10 inches.”

In this tutorial you will write a program that puts a message on the screen where the numbers in it are values for variables.

Skill 1—Correct syntax for fprintf statements1. Read about fprintf commands. We will be using them to print to the screen, but will not be

using them to print to files2. Study the example fprintf command in the box on page 88. Answer the following questions:

a. What does the “%” sign do in the fprintf command? ___________________________b. What does “\n” do and where should it go in the fprintf command? _______________c. If I have %-7.3f in the string, how many places will be provided for the number and

decimal points to fill? (this is called field width) _____________________________d. How many places will be after the decimal point in the above example? (this is called

precision) ____________________________________________________________e. What does the “f” do in the above example? What other conversion characters are

available, and what do they do? ___________________________________________f. What does the “-“ sign do in the above example? _____________________________

Skill 2—Write a short program using the fprintf command.1. Start a new script file in editor-debugger window. Write lines of code to do the following tasks

(in order).a. Clear the screen.b. Display on the screen, “This program will average four numbers.”c. Query the user for the value of the four numbers, one at a time. d. Write a command to average the numbers. e. Now that you have the average calculated, print on the screen (with fprintf) the

following line. Where the XXX.XX is, place the value of the average you calculated.

The average of the numbers is XXX.XX, but you already knew that…

f. Save the program. Run it a few times to make sure it works.


71Skill 3—Make the output look more professionalYour output may look about like this after your run it:

This program will average 4 numbers.Enter the first number5Enter the second number4Enter the third number3Enter the third number6Average = 4.5000The average of the numbers is 4.50, but you already knew that…

I would like you to make it look about like this:

This program will average 4 numbers.

Enter the first number 5Enter the second number 4Enter the third number 3Enter the third number 6

The average of the numbers is 4.50, but you already knew that…

Here are some tricks to improve the appearance:1. Print blank lines to separate things using a disp(‘ ‘) command in the right place in your code.2. Add a space in your input command before the second quote ( …number ‘) so there is a space

between the word number and the number the user enters.3. If your program is printing unwanted stuff on the screen, use the trailing semicolon (;) to stop

it.


72

Matlab: Linear Algebra Tutorial 11

For this tutorial use the following matrixes:

Skill 1—Using Matlab to perform matrix addition/subtraction 1. In Matlab, enter the matrixes listed above in to the workspace by entering each matrix in

the command window.2. Type 2+c, what happened? ___________________________________________________3. Type c+d, what happened? ___________________________________________________4. Type A+c, what happened, why? ______________________________________________

Note: Matlab performs scalar/ matrix addition, but mathematically this statement does not have a solution. The scalar would be represented as a 1x1 matrix and therefore would not be compatible with anything but another 1x1 matrix (or in other words a scalar).

Skill 2— Using Matlab to perform matrix multiplication 1. Type 2*e, what happened? ___________________________________________________2. Type A*e, what happened? ___________________________________________________3. Type (A)(e), what happened, why? _____________________________________________4. If you don’t know why try asking Matlab by typing ‘why’ into the command window.

What happened, why?_______________________________________________________ 5. Type e*A, what happened, why? ______________________________________________6. Type A/e, what happened, why? _______________________________________________7. Write out all of the possible compatible combinations (for multiplication) of the matrixes

listed above (remember as you just found out, order matters). ____________________________________________________________________________________________________

Skill 3— Using Matlab to solve systems of equations using matrix algebraWe can write a system of equations in the linear algebra form as Ax=b, where A is a square matrix representing the coefficients of your variables for your equations you want to solve, x is a column vector with your variables, and b is a column vector filled with the final sum (numbers) of your equations. In algebra we would just divide b by A to solve for x but in linear algebra we cannot divide a matrix by another matrix, so this is not a possible solution path. We can however multiply both sides of the equation by a matrix. Since we want to get rid of everything but x on the left hand side of the equation we want to multiply A by some matrix that will result in the equivalent of 1 (or an identity matrix). That matrix is called an inverse matrix. An inverse matrix is a matrix that, when multiplied by the parent matrix results in an identity matrix.

A-1A=I (where I is an identity matrix)

We can multiply A-1 by both sides of our equation to solve for x.

A-1Ax =A-1b Ix = A-1b x= A-1b (since Ix = x by definition)

1. Read in your Matlab book about inverting a matrix, (there should be about 2 or three commands that do it).


73

2. Solve for x in the equation Bx = e using an inverse matrix.

3. Change B to and try to solve again. What happened, why?_______________

4. To solve the equation Ax =e type, A/e, what happens, why? ________________________5. To solve the equation Ax =e type, A\e, what happens, why? ________________________

In case you wanted to know: The \ command solves equations by using a method similar to forward elimination, backward substitution which will give you more accurate results than the inverse matrix method. This is due to an small accumulation of errors during the process of computing an inverse matrix.

Skill 4— Using Matlab to transcribe a matrix

1. Look up how to transcribe a matrix using Matlab in your book.

2. Find BT=

Matlab: Arrays for vectors and matrices Tutorial 12


74Skill 1—Reason for using arraysIn the last tutorial you wrote a program to average 4 numbers. It worked (if it didn’t—find out so you know how to make it work!), but only for 4 numbers. If you wanted to average 5 numbers, you would need to write a new program. There must be a better way…indeed there is and arrays are one part of how to make it possible!

Anytime you want to keep track of several variables using the same variable name use an array. Think of keeping track of X1, X2, X3, … Xn, but Matlab will call them X(1), X(2), X(3), … X(n). The cool trick is that the number inside the parenthesis (called the argument) can be a variable too.

Matlab will also let you build matrices this way simply by using two arguments… X(1,1), X(1,2), etc. One thing to remember with matrices is that the arguments are row by column. i.e. X(row number, column number).

Skill 2—See the many ways to create arrays1. Spend five minutes and scan the reference book for how many ways you can specify the values

in an array. About how many ways did the book give? _______________________________2. We will be using only one method—directly specifying each element. The other methods are

there if you want them, but are not used much in programming!3. What do the special array commands zeros, ones, and eye do? ________________________

Skill 3—Try out directly specifying elements in an array using the command window.1. Type the command clc and hit “enter” in the command window to clear it off.2. Type the command clear and hit “enter” in the command window to get rid of all stored

variables in Matlab. You can look this command up and read about it if you wish. This is also a good command to put at the beginning of a program—especially if you have arrays in the program.

3. Type Z(2,3) = 5 in the command window, hit “enter”. What happened? __________________4. Type Z in the command window and hit “enter”. What type of variable is Z? What are its

elements? What is the value of Z(2,1)? ____________________________________________5. Type in Z(1,2) = 7 and hit “enter”. Type in Z and hit “enter” to see what the matrix looks like.6. By now your screen is cluttered. Type in clc and hit “enter” to clean it off.7. Type in Z and hit “enter” again. Notice that clc did not get rid of the values of Z. It only

cleaned the screen.8. Type in clear and hit “enter”. Now type in Z and hit “enter”. What value does the computer

have for Z after the clear command? ______________________________________________


75

Matlab: Partitioning a program for easy writing Tutorial 13

Skill 1—Why partition a program?Short programs can be written without much consideration of “how-to-do-it”. Simply write the program. Longer program however can become very complicated. Writing and debugging them can become very difficult tasks. One way to simplify the writing and debugging is to write the program in sections. Each section can then be tested separately.

Skill 2—Examine a program that is partitioned Below is a copy of a program that has been partitioned and filled with comments. Examine the code and answer the questions at the bottom of the code.

clcclear

% ****************************************************************************************%% Input section---All queries to the user for information are here%% Nsamples = How many samples the user wishes to average.% N = Loop counter which identifies which sample the user is entering% Sample = Array (vector) that has the sample values% Largest = The largest acceptable size sample%% **************************************************************************************

Nsamples = input('Enter how many samples you wish to average ');disp(' ')for N = 1:1:Nsamples;fprintf('Enter the value for sample number %2i',N);disp(' ')Sample(N) = input('');end

disp(' ');Largest = input('Enter the largest acceptable size sample ');

%****************************************************************************************%% The next section will calculate the average value for the samples and determine how% many samples are larger than the largest acceptable size.%% Total = the sum of all the samples% Average = the average of all the samples% Ntoobig = number of samples that are larger than the largest acceptable size%% ****************************************************************************************

Total = 0; % Initialize Total and Ntoobig at zeroNtoobig = 0;

for J = 1:1:Nsamples; % This loop will step through the Sample array element by elementTotal = Total + Sample(J); % Add all the values in Sample one-by-one into Total if Sample(J) > Largest; % Check for samples that are too large and increment Ntoobig Ntoobig = Ntoobig + 1; endendAverage = Total/Nsamples; % Calculate the average


76% *********************************************************************************************%% Output section%% *********************************************************************************************

clcdisp('The sample values you entered are as follows: ')disp(' ')for J=1:1:Nsamples;fprintf('\nThe value of sample %2i is %-6.3f',J,Sample(J))enddisp(' ')fprintf('\nThe average of the sample values is %-6.3f',Average)disp(' ')fprintf('\nThere were %2i samples larger than the largest acceptable size of %-6.3f',Ntoobig,Largest)

1. What are the three main sections in this program, and what do they do?Section 1: _________________________________________________________________________Section 2: _________________________________________________________________________Section 3: _________________________________________________________________________2. How could you test section 1 independently of sections 2 and 3? _____________________________________________________________________________________________________________3. How could you test section 2 after you know section 1 works? _______________________________________________________________________________________________________________

Skill 3—Examine the comments1. What information is contained in the section heading comment boxes? ________________________________________________________________________________________________________2. What type of information is given after specific commands? ________________________________________________________________________________________________________________

Note: Whenever you write a program, partition it and add comments to explain how it works.


77

Matlab: Using loops with input and outputs Tutorial 14

Skill 1—When to combine a loop, an input statement, and an arrayIn tutorial 12 you created an array element-by-element. You could (conceivable) build an array of any size, with specific numeric values in each location—just define each element. Such power! This approach however has a few problems:

1. You would need to write out by hand what you needed in the array before building it.2. You would need to know what each element of the array was going to represent.3. You would need to write out the pesky Array(x,y) = N command over and over and over.

Most of these problems can be solved by combining a for-end loop with an input statement and an array.

Skill 2—Run a program that has loops 1. Down load program from tutorial 13 and store it in your own directory. It is available at

__________________________.2. Run the program to feel how it treats the user.3. What elements of the user interface (what gets displayed in the command window while running)

clarify to the user what to do? ________________________________________________4. Does the program always let the user know which sample value to enter when? _________5. How could the user interface be improved? __________________________________________________________________________________________________________________________

Skill 3—Examine the input codeExamine the input section.

Nsamples = input(‘Enter how many sample you wish to average ‘)disp(‘ ‘)for N = 1:1:Nsamples;fprintf(‘Enter the value for sample number %2i’,N);Sample(N) = input(‘’);end

1. What role does the loop counter (the N in a for N=1:1:Nsample) play in the subsequent fprintf command? ___________________________________________________________________

_______________________________________________________________________________2. What role does the loop counter play in the subsequent input command? _________________ _______________________________________________________________________________


78Skill 4—Examine the output codeExamine the output section.

clcdisp('The sample values you entered are as follows: ')disp(' ')for J=1:1:Nsamples;fprintf('\nThe value of sample %2i is %-6.3f',J,Sample(J))enddisp(' ')fprintf('\nThe average of the sample values is %-6.3f',Average)disp(' ')fprintf('\nThere were %2i samples larger than the largest acceptable size of %-6.3f',Ntoobig,Largest)

1. Is it necessary for the output section to begin with a clc command? _________________________2. How does it help the appearance of the display? ________________________________________3. The output section outputs the input as well as the newly calculated values. Is the input more

readable in the way the output section put it on the screen, or the way it was entered (this is a matter of opinion in this case)? ______________________________________________________

4. When might it be a good idea to re-display the input in the output section? ___________________


79

Matlab: Conditional Statements Tutorial 15

Skill 1—Reason for using conditional statementWhen a program runs, it executes the first command, the second command, etc. until it finishes. What do you do if you want a command executed sometimes but not every time? Conditional statements allow the programmer to execute set lines of code if certain conditions are true. These commands can be used for sorting data, looping until a result is obtained, avoiding a “divide-by-zero” error, and many other things.

Skill 2—Proper syntax for conditional statements1. Scan the Matlab reference to learn about relational operators (skip logical operators),

conditional statements, the various if-end commands, and the while-end loop.2. What do the if-end commands allow the programmer to do? ____________________________________________________________________________________________3. What is the difference between the while-end loop and a for-end loop? ___________________________________________________________________________________

Skill 3—Examine an if-end loop in some codeBelow is some code from the program in an earlier tutorial. This code has an if-end command placed in the middle of a for-end loop. (You may need to look at the full original program to remember what the variables were.)

Total = 0; % Initialize Total and Ntoobig at zeroNtoobig = 0;

for J = 1:1:Nsamples; % This loop will step through the Sample array element by elementTotal = Total + Sample(J); % Add all the values in Sample one-by-one into Total if Sample(J) > Largest; % Check for samples that are too large and increment Ntoobig Ntoobig = Ntoobig + 1; endend

1. The for statement matches with the second end statement. We’ll learn more about this later. The if statement matches with the first end statement. How many times will the program execute the if statement? ___________________________

2. What is the value of J on each succeeding time the if statement is encountered? __________3. What condition does the if statement check for? ______________________4. What does the program do if the conditional statement is true? _____________________5. After the program has executed the if-end structure the last time, what does the value of

Ntoobig represent? _________________________________

Skill 4—Rewrite the code1. Modify the program you downloaded in tutorial 13 so that it gives a total of how many samples

are larger than the average. Hint: you will need to add another loop similar to the above loop after the average has been calculated.

2. Have the program display the number of samples that are larger than the average.


80

Matlab: Nested loops Tutorial 16

Skill 1—When to use a nested loopLoops can be put inside each other. This is called nesting. By nesting a loop inside another loop, you can make the program execute a loop several times. Nested loops are used extensively with matrix manipulations. Think of it this way: you could make the first loop (outer loop) operate on each row of the matrix and the second loop (inner loop) operate on each column.

Skill 2—Learn the proper syntax for nested loops1. Read in the reference about nested loops.

Skill 3—Write a nested loop to fill and arrayWrite a short program input section that builds an array called “Samples”.

1. Query the user for how many rows are in the array,2. Query the user for how many columns are in the array,3. Query the user for the value of each element in the array (one-by-one). Be sure to tell the user

what row and column the value will be placed in. For example, the display could prompt the user, “Enter the value for row 5, column 6.”

4. Verify that the program works by trying a small test case.

Skill 4—Write a short matrix manipulation sectionWrite a short piece of code to modify the array “Samples”.

1. Write a nested loop to check the value of each element in the array.2. If the value in the location being checked is less than 5, set it equal to 0.3. If the value in the location being checked is greater than 20, set it equal to 20.4. Create a total of how many values were set to 0 and how many were set to 20.5. Verify that the program works by trying a small test case.

Hint: Don’t forget little things like the clc and clear command. Also don’t forget to set a variable equal to zero before you use it in a command like A = A + 1. If Matlab doesn’t know what A is the first time it executes that command, it can hardly add 1 to it to calculate a new value!


81

Matlab: Debugging techniques and tricks Tutorial 17

In one of the earlier tutorials you learned how to walk-through a program. A “walk-through” is one way of debugging code. Below are some more hints for debugging.

Skill 1—Read the red warning flags carefullyWhen Matlab cannot execute a line of code, it warns the user with a red flag. The flag gives some indication of what was wrong, down to the program line number and column number. The flag is also a hyper-link back to the code so you can get there easily.

1. Read the flag note carefully.2. Sometimes the note doesn’t indicate the precise bug in the code, only the problem that Matlab

had in executing the code.

Skill 2—Echo checksIf reading the Matlab warning didn’t help you find the problem do the following:

1. Suppose the red flag said the problem was on line 32. Go to line 32.2. Note what variables are being used in line 32.3. Insert a few disp commands just before line 32 so you can see what the values of the variables

are when line 32 is executed (line 32 is now “line something else” because you inserted some lines ahead of it).

4. Run the program again. Just before it crashes at (the old) line 32, the program will display the variables to the screen that are used in line 32.

5. Examine these variables carefully. Are they correct???

Skill 3—Test small pieces of codeAfter you finish a small piece of code, test it. Don’t wait until the whole program is complete. For example, when you finish writing an input section, try it out on a simple case. Check the variables for the proper names and values.

Skill 4—Test the program on a small problem firstAfter you’ve finished a program, test is on a small problem that can be checked by hand. Resist the temptation of trying the program on a large problem and then assuming it works “Just Fine!”Download the m-file for Tutorial 17 then inspect the program for errors. See if you can find all 15 of the mistakes.


# Line Error Description1 - 2 3 4 5 6 7 8 9

10 11 12 13 14 15

sii: personal feedback · web viewthe drag coefficient is calculated at the specific reynolds...

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