Authors: Shiuh-Jer Huang, Chiang-Wei Lin
Addresses: Department of Mechanical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Road, Sec. 4, Taipei 106, Taiwan. ' Department of Mechanical Engineering, National Taiwan University of Science and Technology, No. 43, Keelung Road, Sec. 4, Taipei 106, Taiwan
Abstract: Hydraulic active suspension systems have nonlinearity and time-varying dynamic behaviour. It is difficult to establish an accurate model for traditional controllers design. This unknown nonlinear dynamic system is approximated by an second order linear sub-model plus a nonlinear fuzzy sub-model in this study. An on-line recursive least square with forgetting factor scheme is employed to establish this linear sub-model. Then the pole assignment adaptive control strategy is used to control this simplified linear time-varying system. A fuzzy control loop is introduced into this adaptive control structure to detect the unknown nonlinear sub-model for compensating the system modelling error and improving the control performance. The experimental results show that this control strategy has effectively reduced the position and acceleration oscillation amplitudes of vehicle body due to the road surface disturbances. It can be employed to improve the vehicle riding comfort.
Keywords: active suspension system; adaptive control; fuzzy control; vehicle comfort.
International Journal of Computer Applications in Technology, 2004 Vol.20 No.4, pp.152 - 160
Published online: 10 May 2004 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article