Design and Development of a Novel Independent Wheel Torque Control of 4WD Electric Vehicle
In this paper, a novel hybrid vehicle chassis is designed without assisted steering system and its kinematics model, dynamics model as well as a model of the control system. The existing steering mechanism does not provide enough torque or has a shortage of mechanical strength and control. The proposed design has the capability to solve these problems easily. In the first part of this study, the design and development of the vehicle are introduced. After that, a new 4-wheel-drive (4WD) hybrid vehicle chassis including a vehicle platform, a control device, and self-steering mechanism is designed. Its kinematics and dynamics models are built. Furthermore, to optimize the control model and linkage are added between the front and rear bodies. In addition, the new hybrid vehicle chassis has been tested in actual driving. The reliability and feasibility of the vehicle are evaluated by UG software. The open-loop simulation for validation is performed by MATLAB. Finally, traditional proportion-integration-differentiation (PID) control system of the improved model of vehicle chassis is presented. Therein, the PID feedback control loop was employed to track the reference torque of 4-independent wheels. The results are verified using the real-time vehicle. The proposed design is proved feasibility not only has a small turning radius but also has a high control precision, which ensures the flexibility of the vehicle and can control the direction as well. In addition, the proposed design is best for modern agricultural vehicle and can be implemented in commercial and private vehicles.