Study On Nonlinear Control Of Vehicular Stop And Go Cruise Control Systems

Vehicular Stop and Go (SG) cruise control system aiming at the city complicated traffic situation is being paid remarkable attention, which is one of the important research aspects of the advanced safety vehicle technologies. In this dissertation, the study on modeling of vehicular SG cruise longitudinal dynamics, single-input single-output (SISO) nonlinear system control method and its application for realizing the reasonable control of vehicular SG cruise system, and building of vehicle test platform has been conducted based on vehicle dynamics and nonlinear system control theory.The longitudinal dynamics simulation model under the low speed condition is studied firstly. A longitudinal dynamics simulation model describing the system's characteristics and an inter vehicle longitudinal dynamic model, which well represents the driver behavior in the city traffic situation, are obtained. Based on the model of vehicle and inter vehicle longitudinal dynamic systems under driving condition, the nonlinear control method for the vehicular SG cruise control system is studied. A nonlinear vehicle longitudinal dynamics control model and a SG cruise integrating model are deduced. Then, the acceleration tracking controller with input-output linearization method is implemented, and a vehicular SG cruise control algoritm is proposed by adopting output disturbance decoupling method.On the braking condition of vehicular SG cruise system, the control method of SISO nonlinear time-delay system and its corresponding application are investigated. Considering the vehicular SG cruise integrating model under braking condition influenced by some factors of nonlinearity, time-delay and the disturbance, a new nonlinear SMITH predictor is designed to compensate the time delays of control variable in advance. Furthermore, with the resort of pure delay operator, extension of the Lie derivative and the Lie bracket, some issues of SISO nonlinear system with time delays in state variable are resolved, which cover the input-output linearization, invertability of coordinate transformation and the disturbance decoupling problem.the staged transformation and design technique, the vehicle deceleration tracking control and the SG cruise disturbance decoupling control under braking condition are carried out effectively using proposed control method.In order to evaluate the features of proposed nonlinear system control method and its application for the SG cruise system, a prototype vehicle test platform is set up. Moreover, a new type of electronic throttle driving device is developed. Finally, through conducting simulation test and vehicle road test, the control performance of vehicular SG cruise system and the effectiveness of nonlinear system control method are investigated. The results show that the proposed SG cruise nonlinear control systems exhibit the better characteristics of dynamic response, tracking precision and robustness.