Fuzzy logic control of high-speed rail vehicle vibrations on corrugated rail

This paper investigates the performance of fuzzy logic controlled active suspensions on a six-degree-of-freedom rail vehicle model. The vibration control of rail vehicle body and passenger seat is especially important for comfortable travel under high speed. To obtain essential performance requirements for comfort level for the users, a Fuzzy Logic Controller (FLC) is designed. FLC is preferred because of its robust character and superior performance in active vibration control. This vehicle is modeled as a lumped parameter system which consists of a body, bogie, primary and secondary suspension and rigid wheels. The model has been designed to take into account the complexity of wheel-rail contact. Therefore, an adaptive contact model is used for the representation of contact force. This contact model is linearised with the Hertzian spring. At the end of the study, time history and frequency response for accelerations and displacements of the rail vehicle, are presented for the uncontrolled and controlled systems. Performance and advantage of the suggested approach are discussed. 1 INTRODUCTION Railway suspension technology has been investigated in only mechanical engineering discipline, for many years. But now we know that, there are some important vibrations which must be controlled actively for the passenger comfort. Also we have strong foundations for a wider use of such mechatronic techniques. By the increasing of the rail vehicle velocities, it is necessary to investigate the dynamic behaviors and vibrations and comfort problems. Trains are generally considered as two transport modes: active secondary suspensions and active primary suspensions. The paper’s focus is upon this category, which is a general description that can be used to include a number of application opportunities, but is concerned with controlling the rail vehicle body and passenger seat for comfort. Active suspension consists of sensors, controllers and actuators, which apply control forces to the vehicle body. By using parameters such as inertia, spring and damping, the response of a passive system to track inputs or other disturbances is obtained. However the response for an active suspension system is developed by using a control algorithm. In this study Fuzzy Logic Controller (FLC)