Genetic algorithm application in multi-objective optimization of structural parameters and PID controller parameters on bus driver seat's suspension system

The driver seat's suspension system is optimized through a 3DOF quarter-vehicle model. The optimization's objectives are simultaneously minimizing the driver's acceleration and displacement. The elastic element's stiffness kd (N/m) and the damper's damping coefficient cd (Ns/m) are optimized by the Pareto Method with the objective function J(x) designed by the Weighted Square Sum method, and the min value of J(x) is found with the genetic algorithm (GA). A PID controller is integrated into the system to improve the working efficiency, and GA optimizes the controller parameters KP, KI, KD, and N. The optimization processes were carried out under the condition of transient road excitation according to the IRC 99-1988 standard. The results showed that compared to the passive seat with the structural parameters optimized, the active seat with a PID controller reduced 80 - 88% vertical displacement at the driver's mass of 65 (kg), 100 (kg), and 72 - 84% at 80 (kg).