Observer-based multi-objective integrated control for vehicle lateral stability and active suspension design

Abstract

This paper investigates an observer-based robust gain-scheduling integrated control strategy to improve the maneuverability, stability and ride comfort of vehicle by coordinating direct yaw moment control and active suspension system. The uncertainty of tire cornering stiffness, the actuator saturation and the hard constrains of suspension design are taken into account. The longitudinal velocity is considered time-varying which makes the designed controller more practical, and a polytope with trapezoidal structure is used to describe the velocity-dependent parameters. An observer is designed to estimate the vehicle sideslip angle, suspension deflection and tire deflection simultaneously. Based on it, a robust saturated gain-scheduling H∞/GH2 controller is obtained by solving a set of linear matrix inequalities (LMIs), which guarantees that the sideslip angle and yaw rate tracking error are minimized, the vertical acceleration and pitch acceleration are attenuated, and the suspension deflection, tire deflection are bounded. The simulation results illustrate the effectiveness of the proposed integrated control strategy under different road profiles and maneuvers.