研究对象为无人差动转向车辆的动力学控制。通过控制发动机驱动力矩实现车辆的直线行驶，控制左右两侧车轮的液压制动力矩实现车辆的转向行驶，来满足车辆的期望车速与期望横摆角速度需求。相比于传统基于非完整约束模型的差动转向车辆的运动控制，控制算法的设计是建立在分析被控对象动力学模型以及非线性轮胎模型的基础上，考虑到车辆在运动过程中轮胎滑移以及执行器力矩受限对车辆驱制动的影响。基于条件积分方法，设计了抗积分饱和的差动转向车辆动力学控制器，保证了在轮胎力和执行器力矩受限下对参考信号进行准确的跟踪。最后通过实车试验验证了控制算法的有效性。
A dynamic controller is designed for unmanned skid-steering vehicle. The vehicle speed is controlled through engine driving torque to achieve the desired vehicle speed and the steering is controlled through hydraulic braking on each side of the vehicle to achieve the desired yaw rate. Contrary to the common approaches considering non-holonomic constraints, tire slip and saturation of actuators torque influencing the driving and braking are considered,based on the analysis of vehicle dynamic model and nonlinear tire model. Hence, with conditional integrators, the dynamic controller overcoming Integral saturation is designed to ensure the accurate tracking for desired signals under influence of tire forces and constraint of actuators. In the end, the dynamic tracking algorithms proposed are verified by real vehicle tests.
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