H∞ Static Output-Feedback Control with Variable Substitution Scheme for Non-Stationary Running Active Suspension Vehicle

Abstract

In this study, a static output-feedback controller with variable substitution technique is designed to investigate the performance of non-stationary running active suspension. Established non-stationary random road conditions are augmented into the half-car active suspension vehicle system to structure the model as required. Then, the control problem is formulated by properly choosing the controlled and constrained outputs. The vehicle body vertical and angular accelerations are quantified as controlled output, whereas the suspension rattle space, ride safety and actuator limitation are grouped as constrained output. With the aid of variable substitution and linear matrix inequalities (LMIs), the H∞ static output-feedback control (SOFCWVS) is derived. Eventually, the controller will be designed with a special sparsity constraint. The designed controller is applied to the proposed vehicle model and the model responses are compared in the time domain under various controllers. For the time-domain investigation, a non-stationary random road with a class-C profile is utilized. From the simulation results, it is observed that SOFCWVS enhanced the ride comfort more than other control schemes with guaranteed time-domain constrained outputs.