Skyhook and H8 Control of Semi-active Suspensions: Some Practical Aspects

Summary This paper deals with single-wheel suspension car model. We aim to prove the benefits of controlled semi-active suspensions compared to passive ones. The contribution relies on H 8 control design to improve comfort and road holding of the car under industrial specifications, and on control validation through simulation on an exact nonlinear model of the suspension. Note that we define semi-active suspensions as control systems incorporating a parallel spring and an electronically controlled damper. However, the type of damper used in automotive industry can only dissipate energy. No additional force can be generated using external energy. The control issue is then to change, in an accurate way, the damping (friction) coefficient in real-time. This is what we call semi-active suspension. For this purpose, two control methodologies, H 8 and Skyhook control approaches, are developed, using a linear model of the suspension, and compared in terms of performances using industrial specifications. The performance analysis is done using the control-oriented linear model first, and then using an exact nonlinear model of the suspension incorporating the nonlinear characteristics of the suspension spring and damper.

[1]  D. Hrovat,et al.  Optimal active suspension control based on a half-car model: an analytical solution , 1992 .

[2]  Olivier Sename,et al.  Comparison of Skyhook and h∞ Control Applied on a Quarter-Car Suspension Model , 2001 .

[3]  Laura E. Ray,et al.  Robust Linear-Optimal Control Laws for Active Suspension Systems , 1992 .

[4]  D. Hrovat,et al.  Survey of Advanced Suspension Developments and Related Optimal Control Applications, , 1997, Autom..

[5]  P. Mercorelli,et al.  Geometric disturbance decoupling control of vehicles with active suspensions , 1998, Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104).

[6]  Davorin David Hrovat.  Applications of Optimal Control to Advanced Automotive Suspension Design , 1993 .

[7]  T D Gillespie,et al.  Fundamentals of Vehicle Dynamics , 1992 .

[8]  Jong Hyeon Park,et al.  Decentralized variable structure control for active suspensions based on a full-car model , 1998, Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104).

[9]  P. Khargonekar,et al.  State-space solutions to standard H2 and H∞ control problems , 1988, 1988 American Control Conference.

[10]  M. O. M. Osman,et al.  Discrete Adaptive Active Suspension for Hardware Implementation , 1996 .

[11]  Junichi Emura,et al.  Development of the semi-active suspension system based on the sky-hook damper theory , 1994 .

[12]  P. Khargonekar,et al.  State-space solutions to standard H/sub 2/ and H/sub infinity / control problems , 1989 .

[13]  Kisaburo Hayakawa,et al.  Application of H∞ control to active suspension systems , 1994, Autom..

[14]  Shun'ichi Doi,et al.  Improvement of Ride Comfort by Preview Vehicle-Suspension System , 1992 .

[15]  Jae Weon Choi,et al.  LQR approach using eigenstructure assignment with an active suspension control application , 1998, Proceedings of the 1998 IEEE International Conference on Control Applications (Cat. No.98CH36104).

[16]  Olivier Sename,et al.  Simultaneous Decoupling and Disturbance Rejection of an Active Full-Car Suspension Model , 2000 .

[17]  Andrew G. Alleyne,et al.  ADAPTIVE CONTROL FOR ACTIVE SUSPENSIONS. , 1993 .

[18]  Davor Hrovat,et al.  Optimum Vehicle Suspensions Minimizing RMS Rattlespace, Sprung-Mass Acceleration and Jerk , 1981 .

[19]  Luc Dugard,et al.  H/sub /spl infin// control of active vehicle suspensions , 2000, Proceedings of the 2000. IEEE International Conference on Control Applications. Conference Proceedings (Cat. No.00CH37162).

[20]  Wassim M. Haddad,et al.  Active suspension control to improve vehicle ride and handling , 1997 .

[21]  Jong Hyeon Park,et al.  An H∞ Controlller for Active Suspensions and its Robustness Based on a Full-Car Model , 1999 .

[22]  Jo Yung Wong,et al.  Theory of ground vehicles , 1978 .

[23]  M. Nouillant,et al.  From analysis to synthesis of vehicle suspensions: The CRONE approach , 1999, 1999 European Control Conference (ECC).

[24]  E. Yaz.  Linear Matrix Inequalities In System And Control Theory , 1998, Proceedings of the IEEE.

[25]  M. M'Saad,et al.  An Optimal Control Approach for the Design of an Active Suspension System , 1998 .

[26]  M. Hubbard,et al.  A comparison between jerk optimal and acceleration optimal vibration isolation , 1987 .

[27]  J. Doyle,et al.  Essentials of Robust Control , 1997 .

[28]  Alex Liberzon,et al.  Active control for single wheel suspension of off-road track vehicle , 1998 .