Research on fuzzy control of the vehicle's semi-active suspension

The suspension is one of assembly of the modern automobile, the general term of all the force transfer devices between a frame (or chassis and body integral construction) and axle (or wheel). Its main function is to transmit the vertical reaction (supporting force), longitudinal reaction (traction and braking force) and lateral reaction, which are generated by the pavement acting on the wheel, as well as the torque caused by these reactions to the frame (or chassis and body integral construction), thus easing the impact load that the uneven road transmits to the body and reducing the vibration of the bearing system caused by the impact load; at the same time the motion of the body and the wheel should be guided to determine the position of the wheel; when the vehicle is heeling or pitching, the suspension needs to control the posture of the body timely to guarantee the normal running of the vehicle. Therefore, the design of the vehicle's suspension system must fulfill the requirements of ride comfort and handling stability. This paper will establish a nonlinear mathematical model of the semi-active suspension system for four degrees of freedom 1/2 vehicle. The fuzzy logic control method is applied to design the fuzzy controller with different adjustment factors, and then the control simulation software Matlbas/imulnik is used to implement computer simulation.