摘要
通过分析路面附着条件和道路曲率等因素对车辆转向特性和稳定性的影响,建立了高速车辆的等效动力学模型。提出了一种变步长的模型离散化方法,能够在保证车辆模型预测精度的基础上,实现较长的预测时域,并满足计算实时性的要求。通过对高速车辆稳定行驶状态进行分析,推导了基于包络线的滑移稳定性约束条件,并设计了基于模型预测控制的高速无人驾驶车辆的轨迹跟踪控制器。仿真结果表明,该方法可有效保证高速无人驾驶车辆在不同地面附着情况及道路曲率下的操控稳定性。
Through analysis of the effect of road adhesion conditions and curvatures to the vehicle steering characteristics and stabilility, an equivalent dynamic model for high-speed unmanned vehicles is established. A model discretization method with variable steps is proposed to ensure a long enough prediction time domain while maintaining model prediction accuracy and computational feasibility. By analyzing the steady running state of high-speed vehicles, the envelope-based sideslip constraints are concluded and the trajectory tracking controller of high-speed unmanned vehicles based on model predictive control is designed. Simulation results validates that the proposed strategy can effectively ensure the vehicle handling stability under different road adhesion conditions and road curvatures.
引文
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