Team Members: Scott Allen, Kevin Miller, Travis Brack, Paras Ajay
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We then performed some basic calculations to determine the link lengths, number of springs and the spring stiffnesses that we would need to perform a jump of 0.5 meters long and 0.25 meters high. From this analysis we determined that we would like to use 4x4 bar mechanisms to power the jumping, powered by some pretty large, stiff springs (we eventually chose McMaster Carr P/N: 9271K118). In addition, we performed some calculations and did some basic design work to determine the preliminary design of the legs. Finally, we designed the cam that would drive the mechanisms and did some basic calculations to determine the necessary torque our motor would need to drive the mechanisms (speed of the cam was not important to us at this point as we only need the mechanism to slip off the cam in order to perform the jump).
The hand calculations described above are included here:
Design Calculations by Hand.pdf
Furthermore, some preliminary, basic structural analysis was performed to assure that the material used would be strong enough to handle the loads it would encounter without failing. These calculations are included in the excel below.
Leg Static Force Analysis and Motor Selection.xlsx
Materials:
Now that we had performed the necessary calculations, we started to accumulate materials to build our final prototype. We decided to build the mechanism out of aluminum due to it's ready availability as well as our teams' familiarity with the material. In addition, it appeared that aluminum would provide the necessary strength with relatively light weight.
We also purchased a mobile platform from makershed.com, the instruction manuals for the car and arduino setup are attached here for convenience.
Mobile Platform Instruction Manual: http://www.dfrobot.com/image/data/ROB0003/ROB03-Instruction%20MannualV2.0.pdf
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