Design of the fuzzy-PID controller for new vehicle active suspension with electro-hydrostatic actuator

A fuzzy-PID controller is designed for the new active suspension with Electro-Hydrostatic Actuator (EHA). The inputs of the fuzzy controller are displacement of the sprung mass relative to its static balance position (i.e. dynamic deflection) and its changing rate, while its outputs are proportional, integral and derivative gains of PID controller. The paper gives the fuzzy-PID controller's design process and key drive circuits. At the end of the paper, some test results are presented which show that active suspension with EHA using fuzzy-PID control is effective under road conditions with excitations of different frequencies, and that the vertical acceleration of vehicle body and the dynamic deflection of suspension are evidently reduced and that the ride comfort, handling and stability of vehicle are enhanced.