PIT Crew Design Review

1
PIT Crew Design Review
By Dan Chapman, Tim Wilson, and Jon
Miller January 24, 2003
2
Initial Concepts
3
Design Selection
4
Prototype
5
Exploded view
6
Piston Cylinder
3-Way Valve
Modified Ratchet
Regulator
Limit Switch
Bracing Attachment
Air Canister
7
Piston (Bimba)

• Specifications
• 2.5 in Bore
• 2 in Stroke
• Single acting with a spring return
• Will deliver a force of 440 lbf at 90 psi this
  produces a lug torque of 185 ftlb
• Cost
• Piston with a pivot mount is 115.60
• Weight
• 32 oz or 2 lbs

8
Three-Way, Two-Position Valve (McMaster-Carr)

• Specifications
• Max operating pressure of 150 psi
• Actuated by a lever
• Dimensions (2.16 x 2.48 x 1.26)
• Cost
• 73.09
• Weight
• Unknown (estimated .5 lbs)

9
Regulator(Valin)

• Specifications
• 3000psi max inlet and 400psi max outlet
• Cost
• 190.00
• Weight
• 1.5 lbs (est.)

10
Modified Ratchet(Sears)

• Specifications
• Craftsman ½ ratchet driver Model 44809
• Cost
• 21.00
• Weight
• 1.44lbs (excludes adapter and socket)

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Prototype Parts List and Cost Summary
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Prototype Weight Summary

• Piston Cylinder and Mounts 2.46 lbs
• Regulator 1.5 lbs
• 3-way valve (est.) .5 lbs
• Ratchet 1.44 lbs
• Bottle 2.08 lbs
• Housing plate and
• other attachments (est.) 17.7
  lbs
• HP LP fittings (est.) .75 lbs
• TOTAL 25 lbs

13
Prototype Testing

• Goals
• Actual vs. theoretical performance
• Operating pressure
• Torque output
• Safety of system
• Identify which components are overly conservative
• Size and weight reduction
• Worst case scenarios

14
Testing Outcomes
(What we anticipate will happen)

• Optimization of components
• Pre-set regulator
• Minimize number of valves
• Smallest possible canister
• Determine ideal bottle pressure
• Custom piston-cylinder
• Minimum size of total package

15
Prototype Testing Metric
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Biggest Safety Concerns

• High pressurewhat is the minimum operating
  pressure that will give the desired result?
• Hazards analysiswhat pinch-points exist, how can
  they be removed through design?
• Canister safetycan the system be packaged so
  that it cannot be misused?

17
Schedule
18
Concept of Final Product

• Addition of a safety trigger
• Ergonomical layout
• Optimized components