This chapter presents the study of robust active control of an integrated vehicle suspension system that consists of chassis suspension, seat suspension, and driver body models. This integrated system has five control inputs and ten control outputs and each control input may require different feedback signals and have different saturation limits. Taking the measurement available variables as feedback signals, an H_∞ static output feedback controller is designed to improve vehicle ride comfort performance in terms of driver head acceleration under the constraints of actuator saturation, suspension deflection limitation, and road holding capability. The parameter uncertainties to the driver body are considered in the controller design procedure. The controller design conditions, which are expressed as linear matrix inequalities (LMIs), are derived by dealing with each control input separately under a common Lyapunov function so that a feasible solution can be found. Furthermore, force tracking control strategy is applied to implement the proposed control system using electrohydraulic actuators. The improvement of ride comfort is evaluated by using numerical simulations on the driver head acceleration responses under a typical road disturbance.

Chapter Contents:

• Abstract
• 3.1 Introduction
• 3.2 Uncertain integrated system modelling
• 3.3 Robust control system design
• 3.3.1 Control objectives
• 3.3.2 Robust controller design
• 3.3.3 Force tracking control of electrohydraulic actuators
• 3.4 Numerical simulations
• 3.5 Conclusions
• Acknowledgements
• Appendix
• References

Inspec keywords: suspensions (mechanical components); Lyapunov methods; road vehicles; H∞ control; linear matrix inequalities; robust control; control system synthesis; automotive components; feedback

Other keywords: tracking control strategy; seat suspension; LMIs; driver body models; road holding capability; linear matrix inequalities; chassis suspension; suspension deflection limitation; saturation limits; parameter uncertainties; numerical simulations; feedback signals; road disturbance; actuator saturation; electrohydraulic actuators; H_∞ static output feedback controller; controller design procedure; Lyapunov function; driver head acceleration response; driver head acceleration; robust active control; integrated vehicle suspension system

Subjects: Numerical analysis; Control system analysis and synthesis methods; Stability in control theory; Control technology and theory (production); Road-traffic system control; Automobile industry; Linear algebra (numerical analysis); Optimal control; Mechanical components