How hydrostatic propulsion systems work?

A hydrostatic propulsion system is operated for the smooth drive of a vehicle. The propulsion system consists of a shift lever for moving a pump stroking valve into low forward, neutral, and reverses positions of speed to ready the system. After the lever is made into the reverse or forward position, a pedal for the accelerator must be pressed to fully or partially close to an inching valve for the throttle. This needs to be done before the swash plate of the pump moves from zero position of piston displacement and starts pumping the fluid into the hydraulic motors. The motor can be made to high-speed situations by activating the circuit by shifting hydraulic motor swash plates.