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Due to the individual controllability of each motor, the distributed driven electric vehicle has provided a broad research domain for vehicle integrated control. This paper focuses on vehicle stability control by the integration of three systems, the hydraulic brake unit, active steering unit, and motor torque control unit. Firstly, the hierarchical control strategy has been designed generally, which is divided into three levels, the upper controller, medium controller, and lower controller. Secondly, based on the hierarchical structure, each controller has been introduced in detail. The upper controller is the application layer, which has implemented the functions such as the estimations of vehicle states and road conditions, calculation of nominal control variables, identification of vehicle stability and steering characteristics, and the coordinated algorithm of additional yaw moment and active front angle, etc.

Intelligent vehicle formation can improve the driving status of vehicle platoon, increase road traffic flow, reduce traffic accidents, reduce environmental pollution and save energy. As an important part of cooperative platoon control system, cooperative platoon longitudinal speed following control has an important influence on the overall performance of vehicle platoon. To solve the longitudinal speed following control problem of cooperative vehicle platoon, a longitudinal following control strategy based on nonlinear proportion, integration, differentiation (PID) is proposed on the premise of fully considering the delay of vehicle actuator, the delay of vehicle communication and vehicle platoon stability. According to the communication topology structure of Predecessor-Leader Following, the information of platoon state is obtained, and the strategy of constant spacing is adopted. A layered vehicle platoon longitudinal controller is designed based on nonlinear PID control.

A trajectory tracking strategy for an Automated Guided Vehicle (AGV) is presented in this paper, containing a hybrid algorithm of a preview feedforward control and a feedback control via linear quadratic regulator (LQR). The purpose of trajectory tracking is to decrease the position and orientation errors between the trajectory and AGV. The vehicle - road dynamics model applied to establish the relationship between vehicle and trajectory and accurately describes plant motion. The preview feedforward control is adopted to solve time delay of steering mechanism in trajectory tracking. The feedback control via LQR is applied to decrease the errors caused by environmental disturbances. For real-time embedded system, the optimal gain is calculated offline and is used by lookup table online, which could reduce the computation time. The results of tests on a practical AGV system demonstrate the effectiveness and accuracy of the strategy presented in this paper.

A steer-by-wire system has many benefits over conventional steering system for no mechanical link existing between the steering wheel and the road wheels. Road feeling has been being one of the most important vehicle characteristics reflecting vehicle directional control and stability. Besides the steering angle, road wheels reactive torque and vehicle dynamical behavior are considered in this paper. A control strategy with road wheels force feedback and steering wheel angle feedback was developed. The vehicle dynamic states are taken into account for road feeling simulation. Simulation shows that the control strategy achieves desired road feeling, and the second control strategy can improve the road feeling dynamically.