考虑路面摩擦性能的自动驾驶汽车安全制动策略

Safety Braking Strategies for Autonomous Vehicles Considering Road Friction Performance

摘要:

针对现有自动驾驶研究大多忽略路面摩擦性能的问题，制备了5种不同级配的沥青混合料车辙板试件，基于Persson表面分形摩擦理论和轮胎?路面三维有限元模型，求解沥青路面的动摩擦系数和附着系数，表征其摩擦性能，并使用Matlab/Simulink软件建立自动驾驶汽车的动力学控制模块，根据车辆期望制动减速度和道路摩擦性能逆向反推求解轮缸的制动压力值，实现自动驾驶汽车的制动过程。使用CarSim软件和Matlab/Simulink进行联合仿真，设定了下坡制动和曲线制动工况，分析了纵向坡度、弯道半径和道路超高等影响因素对自动驾驶车辆制动效能的影响。

Abstract:

In view of the problem that most of the existing researches on automatic driving ignore the friction performance of pavement， five kinds of asphalt mixture rutting plate specimens were prepared in this paper. Based on Persson’s surface fractal friction theory and the 3D tire-pavement finite element model， dynamic friction coefficient and adhesion coefficient of asphalt pavement were calculated to characterize the friction performance. Matlab/Simulink software was used to establish the dynamics control module of autonomous vehicles， and the braking pressure of the wheel cylinder was solved by reverse calculation based on the desired braking speed and pavement friction performance of the vehicle to realize the braking process of the vehicle. Finally， CarSim and Matlab/Simulink were used for co-simulation， setting downhill braking and curve braking conditions， and analyzing the influence of factors such as longitudinal slope， curve radius， and pavement superelevation on the braking performance of autonomous vehicles.