Selection Analysis Presentation

ME 4182Team: 5 Guys Engineering + 1

Nathan Bessette, Rahul Bhatia, Andrew Cass,

Zeeshan Saiyed, Glen Stewart

YJ Chok

Automatic White Board Wiper

• Last Time– Presented conceptual designs• Brief descriptions• Sketches• Pros and cons

– Received criticism of our conceptual designs• Went back and reworked conceptual designs• Conducted calculations on board/ eraser friction

Feasibility Testing

Calculations

Using the situation with the heavy writing

5”

2”

For 9.6 erasers to span the height of the board

For 4.8 erasers to span half the height of the board

Magnetic Whiteboard Cleaning System• Pros

– No bulky apparatus present in front of board, most of system present behind whiteboard

– Eraser could be used manually for selective cleaning by user

• Cons– Requires invasive installation, may

cause whiteboard to protrude from wall

– May require lengthy time to completely erase board due to small eraser size

• Points of interest– Uses electro magnets combined

with rails to create vertical and horizontal motion

– All moving parts except for the eraser are placed behind the board

Multiple Wiper System• Pros

– Multiple wipers divide board into quadrants

– Multiple wipers do the work so wipers do not get dirty as fast

– Motors are mounted behind board to provide a low profile

• Cons– Multiple motors raises cost– Controls needed to

coordinate quadrant cleaning

– Motor replacement would be intrusive

Scissor Spring Board Eraser• Pros

– Easy eraser replacement

– High force applied to board

• Cons– Requires maintenance– Intrusive, occupies 3-D

space– Multiple motors

• Points of interest– Allows for even

erasing– Five points of contact

for less required pressure

This particular design concept utilizes a horizontal felt bar with 3 spring arms attached to the bottom and 2 spring arms originating from the top, affixed to the front plate of the eraser mechanism. The AC-powered controller will drive 2 motors, on top and bottom, propelling a belt to index to the next quarter section. The device will return to position to the left of the board real estate when not in use.

Dual Swipe Cleaning System• Pros

– Low profile design– Relatively fast erasing time– Low surface area of eraser leads

to low friction force– Does not require custom parts

• Cons– Takes up space on 3 sides of the

board– Employs long chains to drive

cleaning apparatus• Points of interest

– Uses combination of chain drives and rails to drive main arm across board

– Eraser has vertical movement and is as long as half the height of the board

Other Designs Considered

Roller Wiper

Zen Buffer

Selection Criteria

• Cleanliness/ Effectiveness• Complexity• Cost• Consistency• Safety• Size• Speed• User Effort

Weighting

• Weighted on a 1-5 scale (5 being the most important)– Cleanliness/ Effectiveness [5]– Complexity [3]– Cost [2]– Consistency [4]– Safety [3]– Size [4]– Speed [5]– User Effort [3]

Baseline

Evaluation Matrix

Findings

• Weights were multiplied by raw scores to get total scores

• Total scores were summed and normalized– Baseline hand wiper had a normalized score of 0.76– Dual slide design had a normalized score of 1.0– Roller wiper had a close normalized score of 0.89

Automatic White Board Wiper

• Next Time:– Midterm Presentation• Who we are and what we are doing• Summarize work done so far• Graphical aids• Mockup