OHCHS Physics Department - Slingshot

In mid-February 2022 The OHCHS Physics Department came to OHTS Pre-Engineering to request the manufacture of a new physics slingshot. This was to replace the old homemade wooden slingshot that the school had been using which was becoming very old and imprecise. Two classmates and I were assigned to create a new slingshot with a deadline of late March to early April. What is meant by a "physics" slingshot is that measurements can be made. This meant that there were to be force indicators and angle selectors.

My team and I researched some slingshots online looked at the old slingshots and got a general design down. Our idea was to have a full aluminum frame with two towers on each end with one larger tower having the slingshot elastic cords attached (the launch side). The other shorter towed would have a crank and a tensioning cord (the trigger side). This would all run through pulling in the center of the base of the frame that would allow the slingshot to point up but pull the tensioning cable in the upward direction too.

The frame was designed and the measurements were made and drafted on paper to ensure that all parts would fit together since there was limited extruded aluminum for the manufacturing. Frank Damond and another team member cut all the aluminum for the frame and began assembly. I worked with a Senior Level Pre-Engineering student Dawson Joseph to create a triger system.

The trigger system was a flip latch which was tied in the middle of the tensioning cord. This trigger had an "L" shaped piece that rotated along a small frame. A loop was tied and bound in the tensioning cord so that the loop could hook around the "L." A second hinge was made that would hold the "L" in place and had a trigger cord that could be pulled on to relieve the loop from the hook. this was all assembled and thread-locked and functioned as designed.

For force measurement, there were markings made in the tensioning cord that would give a rough estimate of the Newtons that the elastic potential energy the bunjy cords had to exert. There was a crank winch used to tension the cords to keep users away from the launch side and torqued to crank with ease. The device was fully assembled tested and delivered to the Physics Department mid to early April due to delays from school snow days.