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1 ECE 495 Integrated System Design I ECE 495 - INTEGRATED SYSTEMS Requirements Specifications and Standards Timothy Burg

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ECE 495 Integrated System Design I Life Cycle of a Troubled Project Project Initiation Wild Enthusiasm Disillusionment Change Search for the Guilty Punishment of the Innocent Promotion of the Nonparticipants Definition of the Requirements

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ECE 495 Integrated System Design I Design Example Mars Orbiter Crash In 1999, NASA lost the $125 million Mars orbiter Failure was attributed to conversion between metric and English measurement units between contractors Lockheed Martin used English measurements NASA navigation team used metric measurements The contractor, by agreement, was supposed to convert its measurements to metrics

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4 ECE 495 Integrated System Design I Generic Design Process Identify Need Research Requirements Specification Concepts Design Prototype Testing Retire Maintain Use by Customer(s) Distribute and Sell Manufacture Lesson: A successful project will have a technical agreement between all parties (and they will monitor and enforce the agreement).

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5 ECE 495 Integrated System Design I Requirements Collection of engineering and marketing targets that a design must satisfy Mission statement that drives all subsequent stages of development Communication tool for everyone involved in the design; Engineering, Marketing, Client, In some cases serves as a legal binding contract Every important detail about what is expected is written in this document. All parties should understand the size, weight, reliability, electrical performance, etc. expected in the final product.

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6 ECE 495 Integrated System Design I Design Example Gamma-Ray Large Area Space Telescope (GLAST) Customers Vision Design Team Harmonize the vision for the telescope through a Requirements Document

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7 ECE 495 Integrated System Design I Design Example Gamma-Ray Large Area Space Telescope (GLAST) http://xweb.nrl.navy.mil/glast/ Gamma-Ray Large Area Space Telescope Telescope developed by NASA in collaboration institutions and partners in France, Germany, Italy, Japan, Sweden, and the United States. The subsystems designed (independently) by each group must be assembled and work together to perform the function of GLAST Calorimeter: US, France, Sweden

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8 ECE 495 Integrated System Design I Design Example Gamma-Ray Large Area Space Telescope (GLAST) One important component (PIN Diode)

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9 ECE 495 Integrated System Design I Design Example Gamma-Ray Large Area Space Telescope (GLAST) Used Standards to describe how routine items are done.

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10 ECE 495 Integrated System Design I Design Example Gamma-Ray Large Area Space Telescope (GLAST) This all-sky view from GLAST reveals bright emission in the plane of the Milky Way (center), bright pulsars and super-massive black holes. Thousands of pages that describe what the system should do and how well.

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11 ECE 495 Integrated System Design I Two Types of Requirements Specifications Marketing Requirements What Customer Wants high-quality audio fast easy to use Engineering Requirements Technical Targets 2% distortion 100 mph 3 button interface, on-off, volume, balance

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12 ECE 495 Integrated System Design I Marketing Requirements Determine the voice of the customer. May require asking what the customers wants Customer may communicate solutions with the needs. Need to understand source of solutions and if really appropriate I want a 1KW motor controller for may actually mean I want to control the speed of the conveyer in . These are likely different solutions.

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13 ECE 495 Integrated System Design I Engineering Requirements Quantify the voice of the customer 10 grams 2% distortion 100 mph 3 button interface

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14 ECE 495 Integrated System Design I Properties of An Engineering Requirement Abstract Specify what the system will do, not how Unambiguous Single stated meaning with short complete sentences Traceable Each requirement is a response to the customers need Verifiable Can measure that the requirement is met

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15 ECE 495 Integrated System Design I Engineering Requirement Examples Performance and Functionality Accuracy and speed Reliability and Availability Failure rates and amount of time that a system is available for operation Energy Energy consumption Operating lifetime +/- 0.1 mA, 800 mm/sec Mean time between failures (MTBF) = 30,000 hours

20 ECE 495 Integrated System Design I Engineering Standards 550 standards issuing bodies in the United States National Fire Protection Association (NFPA) Trade association (organization founded and funded by businesses) Publishes the National Electrical Code (NEC) Federal Communications Commission (FCC) An independent agency of the US government Enforces standards ANSI (American National Standards Institute) Private non-profit organization To aid portability between compilers defined ANSI C -> ISO C -> Standard C ANSI paper sizes: A:8 11

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21 ECE 495 Integrated System Design I Engineering Standards 550 standards issuing bodies in the United States (cont.) The Institute of Electrical and Electronics Engineers (IEEE) is a professional association Professional society (EEs and CpEs) 800 standards products Examples: 802.11, FireWire National Institute of Standards and Technology (NIST) Government agency Atomic clock, Weights and Measures Antenna calibrations 2012 budget $750,800,000

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22 ECE 495 Integrated System Design I Engineering Standards Must I Follow a Certain Standard in My Design? Voluntary Standards Adopted for the sake of ease of manufacture, interchangeability, and safety May be used in an exclusionary way, to favor one group or organization over its rival Mandatory Standards Standards which are laws Failure to follow would result in legal penalty They are generally adopted out of concern for safety

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23 ECE 495 Integrated System Design I Engineering Standards Types of Standards Definition Standards Standards that provide standard measurement, symbology or terminology SI or Standard system of measurement Performance Specification Standards Doesn't matter how a thing is made or done, but it defines a certain level of performance Blu-Ray, USB 3.0, FireWire 800 ( IEEE 1394b-2002 ) Criteria Standards How to go about an activity, kind of the "opposite" of a performance standard.

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24 ECE 495 Integrated System Design I Example US FCC Describes Use of the Radio Spectrum

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25 ECE 495 Integrated System Design I Example US FCC Describes Use of the Radio Spectrum What type of standard? Definition Standard Performance Specification Standard Criteria Standard Voluntary or Mandatory Standard

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26 ECE 495 Integrated System Design I Example: IEEE-STD-299-1997 Standard Method for Measuring the Effectiveness of Electromagnetic Shielding Enclosures What type of standard? Definition Standard Performance Specification Standard Criteria Standard Voluntary or Mandatory Standard Note: Cost $150 to purchase

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27 ECE 495 Integrated System Design I Example Standard for Specification of Requirements IEEE Standard 1233, Guide for Developing System Requirements Specifications Properties of the Requirements Specification (the set of all Engineering Requirements) Normalized set Complete set Consistent Bounded Granular (Abstractness) Modifiable

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28 ECE 495 Integrated System Design I Engineering Standards Who Writes Standards? You and your colleagues.

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29 ECE 495 Integrated System Design I Standards and the Design Process Identify Need Research Requirements Specification Concepts Design Prototype Testing Retire Maintain Use by Customer(s) Distribute and Sell Manufacture Standards give a good point to start or at least narrow down your research Usually standards help in describing expectations Testing- Standards should be met for all tests conducted on product

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30 ECE 495 Integrated System Design I Example: Marketing Requirements for a Controller for a Roller Bottle Incubator Apparatus ? Motor and controller System that turns bottles in an incubator. What is in the Marketing Requirements and the Engineering Requirements? Cells Media

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31 ECE 495 Integrated System Design I Example: Marketing Requirements for a Controller for a Roller Bottle Incubator Apparatus The customer has asked for the following, what are the Marketing Requirements? Wheaton Science Products seeks an apparatus to enable you to easily scale-up anchorage-dependent cell lines from standard plastic flasks. Benefits of the Roller Bottles are the increased surface area, gentle agitation and improved gas exchange when cells are rotated out of the medium. All models are CE/UL/CSA marked for international use and are available with different electrical plug configurations. Economy bench models allow inexpensive entry into this technology with units rotating from one to eight bottles. For vaccine production or when high yield is needed, use the Wheaton Modular Cell Production Apparatus and add decks that will hold additional bottles, as needs increase. Backup battery systems and rotation alarms can also be added to any Wheaton Roller Production Equipment. Wheaton Roller Apparatus accommodates standard culture vessels, 108 to 121 mm in diameter and up to 550 mm long.. Rotation speed can be set by the user.

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32 ECE 495 Integrated System Design I Example: Engineering Requirements for a Controller for a Roller Bottle Incubator Apparatus Map Marketing Requirements to Engineering Specifications Gentle agitation -> acceleration rate rad/s/s CE/UL/CSA marked -> testing per UL standards **** testing per CE standards **** testing per CSA standards **** International use -> 100V-240V input range Economy, Inexpensive -> control system components