Ride Comfort Enhancement of Semi-active Vehicle Suspension Based on SMC with PID Sliding Surface Parameters Tuning using PSO

This paper presents a sliding mode control (SMC) using proportional-integral-differential (PID) sliding surface (SMC-PID) for semi-active vehicle suspension system utilizing magnetorheological (MR) fluid damper to enhance ride comfort. The fundamental concept is that the robustness property of SMC and good response traits of PID are incorporated to accomplish more acceptable overall performance. The sliding surface design is modified based on PID and is derived from the developed dynamic equations. A dynamical model for five-degrees of freedom half car committing MR damper is developed. The particle swarm optimization (PSO) technique is applied to solve the nonlinear system optimization problem to find the PID sliding surface controller parameters. Optimal setting of these parameters will improve dynamic response and ensure stability of the system. Capability of the proposed controller has been evaluated by numerical simulations. Comparisons with MR-Passive and conventional SMC system have also been provided. From the observation of the simulation results, compared to the MR-Passive system and conventional SMC controlled system, the SMC-PID controlled system can offer a better ride comfort at adapting bump and random road excitations.