tailieunhanh - A new nodeling of the Macpherson suspension system and its optimal Pole-Placement control

 In this paper a new model and an optimal pole-placement control for the Macpherson suspension system are investigated. The focus in this new modeling is the rotational motion of the unsprung mass. The two generalized coordinates selected in this new model are the vertical displacement of the sprung mass and the angular displacement of the control arm. | Proceedings of the 7th Mediterranean Conference on Control and Automation MED99 Haifa Israel - June 28-30 1999 A New Modeling of the Macpherson Suspension System and its Optimal Pole-Placement Control Keum-Shik Hong Dong-Seop Jeon School of Mechanical Engineering Graduate College Pusan National University Pusan National University Pusan 609-735 Korea Pusan 609-735 Korea Hyun-Chul Sohn Graduate College Pusan National University Pusan 609-735 Korea Abstract In this paper a new model and an optimal pole-placement control for the Macpherson suspension system are investigated. The focus in this new modeling is the rotational motion of the unsprung mass. The two generalized coordinates selected in this new model are the vertical displacement of the sprung mass and the angular displacement of the control arm. The vertical acceleration of the sprung mass is measured while the angular displacement of the control arm is estimated. It is shown that the conventional model is a special case of this new model since the transfer function of this new model coincides with that of the conventional one if the lower support point of the damper is located at the mass center of the unsprung mass. It is also shown that the resonance frequencies of this new model agree better with the experimental results. Therefore this new model is more general in the sense that it provides an extra degree of freedom in determining a plant model for control system design. An optimal pole-placement control which combines the LQ control and the pole-placement technique is investigated using this new model. The control law derived for an active suspension system is applied to the system with a semi-active damper and the performance degradation with a semi-active actuator is evaluated. Simulations are provided. 1 Introduction In this paper a new model of the suspension system of the Macpherson type for control system design and an optimal pole-placement control for the new model are investigated. The roles