The Jonova Engine is a simple pump design, modified and adapted for use as an internal combustion engine. There are currently no mass produced vehicles that use this as an engine because it hasn't shown much promise for the application. A recently revised version of the Jonova Engine was designed and built by students at the University of Arizona, as pictured on the left. The design uses circular motions which create sealed chambers that allow combustion to keep them spinning. Because of its limited number of moving parts (four in the most recent design), it has very little rotationa inertia to overcome, and its design eliminates energy lost through vibration (a major problem with piston engines). Another advantage it has over piston engines is its enduring power stroke, being two thirds of a rotation, as opposed to the piston engine's one-fourth.