Tri-Better Detailed Design Review

Transcription

1 Tri-Better Detailed Design Review Designers: Michael Kurvach Nathaniel Morefield Ryan Wilson Cody Woods Guide: Dr. Richard Lux

2 Project Overview The goal of this project is to create a shoe and pedal which reduces cycling to running transition time without compromising cycling or running speed.

3 Customer Needs Critical Needs Flexibility while running Lets the triathlete transition faster Shoes can be left on the pedal when not in use Easy clip out Good power output Long pedal life Secure attachment to pedals Non-Critical Needs Easy clip in Comfortable Float and Adjustability in the Pedal

4 Assembly

5 Section View

6 Front Clip

7 Specifications Specification (metric) Units Marginal Value Ideal Value Comments Required force to flex the forefoot 45 degrees N <= 30 Force is applied by placing shoe in compression toe to heel. Time saved in transition 2 s >=0 >=10 Transition 2 is switching from biking to running Shoe can be mounted on bike without rider Y/N Yes Yes Percent of triathletes successfully clip and out after 30 minutes of practice % Percent of triathletes successfully clip out after 30 minutes of practice % Percent power output of benchmark model % Factor of Safety for infinite life on pedal >=3 >=5 Vertical force required to unclip from pedal N >= 1500 >=3000 Percent of triathletes willing to repeat a sprint triathlon distance in the shoes % >=50 >=80 Degrees of float deg >=0 >=15 Float is rotation on the pedal about the vertical axis Clearance between bike frame and shoe mm >=1 Forward backward pedal position adjustment range mm >=5 >=10 Degrees of rotational adjustment possible around the forward/backwards axis deg >=0 >=5 Shoe weight g <=370 <=200 Running mode Combined pedal and shoe weight g <=700 <=500 Cycling mode The amount of inversion/eversion of the foot should be adjustable.

8 Estimated Weight Volume (cm^3) material Density(g/cc) Mass (g) pedal carbon fiber coupling aluminum Spindle & bearings steel 90 washer top front 4.07 aluminum washer bottom front aluminum washer top back aluminum washer bottom back aluminum spacer front aluminum spacer aluminum spacer aluminum spacer aluminum spacer back aluminum filler balsa wood Shoe + EVA + rubber 200 In shoe heel clip delrin Heel Clip nylon 6/ clip nylon/aluminum TOTAL (carbon fiber) TOTAL (Aluminum) TOTAL (Running) (1.4 lb) 807 (1.8 lb) 204 (.45 lb)

9 Systems Architecture 1. Pedal Coupling Easily attached to premade spindle Allow rotational adjustment of pedal 2. Pedal Provide rigidity for cycling power transfer Allow forward/backward adjustment of foot Interface with coupling, front, and rear clips

10 Systems Architecture 3. Front Clip Allow Stomp clip in Provide float to the rider Allow twist release Provide failsafe 4. Rear Clip Allow stomp clip in and twist release Hold ankle to pedal 5. Shoe Sole Provide a comfortable running surface Support the foot

11 Testing (To Date) Goal Determine whether restricting heel affects power output Familiarize team with Towpath testing equipment Results No numerically significant data Qualitative data from Dr. Haefner that a bolted heel is easier to cycle with

12 Shear Stress on Front Clip

13 Heel Clip Force Pulling Up Forces

14 Pulling Y Displacement

15 Pulling Y Displacement Al

16 Pulling Z Stress Layer 2

17 Pulling Von Mises Layer 1 Al

18 Pushing Z Stress Layer 2

19 Pushing Von Mises Layer 1 Al

20 Pushing Z Stress Layer 14

21 Pushing Von Mises Layer 15 Al

22 Pushing Foam Von Mises Stress

23 Proof of Concept Model: Front Clip

24 Proof of Concept Model: Rear Clip

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45 Risk Assessment ID Risk Item Effect Cause Likelihood Severity Importance Action to Minimize Risk Owner 1 Unable to work effectively with carbon fiber Prototype would not be made correctly or on time. Might become too costly Long learning curve to working with the material Start with a simplified practice lay up. Also, join the Formula composites team and recruit their assistance Ryan 2 Clipping in becomes too difficult Added time in the event of a crash and irriation to the customer High Forces required to deform the EVA Revert to a twist to latch design using using geometry over deformation. Cody/Mike 3 Clipping out becomes too difficult Slow transition times Overly complex locking system requiring too much coordination or force to clip out Revert to a twsit to latch design using gemometry over deformation. Mike 4 Design becomes too heavy for customer Fatigues Racer Over Engineering/High Volume Use Low density Materials. Keep Factors of Safety Reasonable. Complete Nate/Ryan an early weight analysis of each component 5 Failure to distribute pressure from clip Discomfort on the sole of the foot Midsole is too soft around the clip Use a large washer design in the shoe but a small clip (1''dia). Vary EVA hardness in shoe Mike/Cody

46 Bill of Materials/Budget Material Use Cost ($) Supplier Bike Pedals Spindle, Cup & Cone Washers bought Barge Cement Gluing sole onto upper bought 6061 Aluminum Bar 3 x 1.5 x 18 Couplings, Spacers, front clip Speedymetals 6061 Aluminum Plate.04 x 1' x 1' Washers Speedymetals 1/8 ball bearings pedal coupling 2.90 Mcmaster Carr vacuum bag sealant tape carbon fiber Jamestown carbon fiber unidirectional cloth 1 yd. carbon fiber Jamestown epoxy resin 1 qt. carbon fiber Jamestown slow hardener carbon fiber Jamestown carbon fiber weave carbon fiber Jamestown Nylon Release 2 yd carbon fiber Jamestown Breather carbon fiber Joann Fabrics 24 x 48 x.75 balsa wood carbon fiber fibreglast 2 x 10 x 8 pressure treated lumber carbon fiber mold Home Depot 5 piece diamond coated rotary cutting discs carbon fiber 5.00 Harbor Freight 1/8 x 2.5 x 2' delrin sheet clip shoe inserts 9.30 Mcmaster Carr 3/8 x 2 x 1' delrin sheet clip shoe inserts 8.94 Mcmaster Carr 1 x 1' Nylon 6/12 rod rear clip insert Mcmaster Carr Shoes upper water jet machining time clips N/A shoe parts (EVA, rubber) sole shipping costs fibreglast 9.95 Speedymetals Mcmaster Carr Jamestown Total

47 MSD II Machining To Do List Subsystem Coupling Pedal Front Clip Back Clip EVA Sole Operation Time Estimate (hours) Week Machining (drilling/milling/finishing) 10 1 Constructing with Existing Pieces 1 1 Machine Outer Spacers 2 1 Machine Tube Spacers 2 1 Machine Back Spacer 2 1 Machine Washer Plates 2 1 Construct Foam Center 9 2 Machine mold (wood) 2 1 Plastic Form? 2 1 Sanding 1 1 Make Template 1 3 Cut Layers 1 3 Layer Carbon 3 3 Setting/Vacuuming 2 3 Finishing 6 3 Provide WJ Specs to Brinkman Lab(Washer, Clip) 3 2 Machine Base 3 2 Machine Clip 2 2 Provide WJ Specs to Brinkman Lab(Shoe Insert) 1 2 Machine Radius on to Clip 2 2 Hand Cut Front Clip 2 3 Hand Cut Rear Clip 2 3 Assembly and Finshing (Attach to Upper) 2 3

48 MSD II Testing Plan Customer Need Variable Resource Requirements Flexibility while running Deflection Force sensor Running time Shoe prototype, existing running shoe Faster Transition Transition time Bike, pedal/shoe prototype Shoes able to be left on pedal Yes/No Bike, pedal/shoe prototype Easy clip out Time Bike, pedal/shoe prototype Force Force sensor Good power output Wattage Towpath testing equipment Cycling Time Long Pedal Life # Uses N/A Yield Strength Bike, pedal/shoe prototype, existing cycling shoe and pedal Materials Science lab Secure attachment to pedal Force Force sensor