ME329 Design Project #1 Professor James Widmann

ME329-08

Alex Choi Brandon Stell

Lawrence Yang

Customer Requirements

• Increase physical activity levels

• Limited muscle incorporation

• Active participation & engagement

Photo courtesy: http://www.avidall.com/5-lessons-learned-from-my-cerebral-palsied-brother/

Engineering Requirements

• Design a machine to shoot rings 6 feet away onto a 6 x 6 array of bottles

• Single hand operable within a 6 inch sphere

• Adjustable in 2 different angles

• Materials:

• LEGO Technic

• Motor & Battery Pack

• Low cost materials

How “The Claw” WorksGear Reduction

How “The Claw” WorksRope Pulley System

How “The Claw” WorksSafety Trigger Release

How “The Claw” WorksAngle Adjustability

Motor and Power Source• Motor: Sanko M9I6OU22-1

• Battery: 9V Rayovac Ultra Pro

• Efficency: 22%

• Output Power: 2.39 W

0"

0.1"

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0.7"

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0.5"

1"

1.5"

2"

2.5"

3"

0" 2" 4" 6" 8" 10" 12" 14" 16" 18"

Efficien

cy(

Outpu

t(Pow

er((W

a4s)(

Torque((N:mm)(

H"(Wa0s)"

efficiency"

0"

1000"

2000"

3000"

4000"

5000"

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7000"

8000"

0.00"

0.20"

0.40"

0.60"

0.80"

1.00"

1.20"

1.40"

1.60"

0" 2" 4" 6" 8" 10" 12" 14" 16" 18"

Speed%(rpm

)%

Curren

t%(Am

ps)%

Torque%(N4mm)%

Current"

Speed"

Cost and Weight

• Total Cost: $24.00

• Lego Cost: $20.75

• Radio Shack Switch: $2.00

• 9V Battery: $1.25

• Total Weight: 3.5 lbs

• Weight of Machine: 1.89 lbs

Accuracy

Pulley-Pulley Center

Distance (Inches)

Average Horizontal

Toss Distance

(feet)

Number of Trials Accuracy

Picture Marker Color

Identification

1 7.5 3 Low-Medium Black

1.5 6 3 Medium Red

2 5 3 High Blue

Conclusion: Lessons Learned

• Over complicating adds unknowns

• Entire LEGO deflection

• The higher the tension

• Higher deflection/bending

• Lower Accuracy

• Foam core used as damperPhoto courtesy: http://socialstrategist.com/wordpress/wp-content/uploads/2010/12/SuccessFailure.jpg