​​How it works

The rotating base is composed of a lazy susan, two circular aluminum plates, two bicycle sprockets and a chain, and a small motor. The chain connects the two sprockets and a gear ratio is utilized to effectively power the rotating base. The aluminum plates are large enough to safely house the catapult, but not much larger due to the space available on top of the fridge. The larger sprocket is sandwiched between the plates, with hoop-like spacers in between the plates and the sprocket to account for the height of the chain. The whole system is bolted onto the lazy susan, which in turn is bolted onto the fridge. We also incorporated a bearing and bolt feature to the rotational axis of the system to pre-load the lazy susan. Since a lazy susan is commonly used in situations that require compression, the bearing and bolt feature is added to eliminate deformation of the lazy susan during the launching of the catapult.