Task Definition: Launch a tennis ball the farthest horizontal distance with a stationary device that fits within a 12 x 12 x 12 in. cube within 15 seconds of actuation. Analyze the motor to determine optimal capstan radius. Conduct FEA analysis on components to determine failure points. Use mass-efficient design to optimize catapult design.

Custom Materials: 3D Printed Tough Ultimaker PLA, Aluminium 6061, 1/8 in. Steel Sheet Metal.

Stock Materials: Tamiya 72001 gearmotor kit, Stainless Steel Extension Springs, Various Hardware.

Results:
Average of 10.23 J of work done on Spring

Average 14.7 s release time

Average 245 in. traveled

Average of 132.5 N exerted on arm

Analysis Conducted on Catapult:

A wide variety of analysis was conducted on this catapult, including but not limited to:
FBD analysis of arm, primarily looking at failure modes of beam bending and buckling. This was then inputted into Fusion 360 to allow for FEA analysis.
Structural analysis of catapult frame, check for buckling along the two force members. This allowed us to use mass-efficient design to optimize our catapult into the triangular shapes seen in the final design.

Motor analysis (not pictured), using experimental trials to determine the motor constant k, internal resistance R, and per stage efficiency. This was then used to calculate motor torque, in order to optimize the capstan radius.