The DC motor is connected to an H bridge, powered by a battery. Its capacity was deliberately chosen to be very low, so that the effect of the discharge would be visible during the simulation (1 minute). The speed control allows following a constant reference. The PID regulator generates a command signal which is converted into a direction / PWM cycle by the “CalculRapportCyclique” subsystem. These two signals are converted into 4 PWM signals used to drive the H bridge.