非匹配不确定和状态时滞扰动下的车道线保持

Vehicle lane-keeping control under state time-delay and mismatched uncertain perturbations

针对车道线保持控制中存在的不确定性扰动及时滞问题,提出一种自校正滑模控制方法.该方法利用线性矩阵不等式理论给出滑动模态存在的充分条件;系统在滑动模态下对于存在的非匹配不确定性扰动以及状态时滞具有完全不变性.接下来引入双极性sigmoid函数代替常规滑模控制中的符号函数并设计自校正律;在自校正律的作用下使sigmoid函数的边界层厚度以及切换增益可根据系统状态进行自适应调节,从而达到削弱控制器输出抖振的目的.基于Lyapunov理论对该方法的稳定性进行了证明,最后通过车辆的车道线保持仿真实验对该控制方法的可行性及有效性进行了验证.

To deal with the mismatched uncertainty and state time-delay perturbations in vehicle lane-keeping control, we propose a self-turning sliding mode control method. By using the linear matrix inequality theory, we develop the suffi- cient conditions for the existence of the sliding-mode, in which the system in the sliding phase is completely independent to the existing mismatched uncertainties and the state time-delay. The sigmoid function is adopted to replace the sign function in designing the self-tuning law, by which the boundary layer of the sigmoid function as well as the switching gain can be adjusted automatically to reduce the high frequency chattering in outputs. The stability of the control method is proved based on Lyapunov theorem. Simulation results show the correctness and feasibility of the proposed method.