汽车驾驶机器人研究中的一个关键问题就是多机械手的协调控制。为了实现驾驶机器人换档机械手和油门、离合、制动机械腿的综合协调控制,最终实现对给定循环行驶工况的车速跟踪,首先建立了基于Saridis G N三级控制架构的驾驶机器人递阶控制模型体系结构,然后在此基础上提出了驾驶机器人多机械手协调控制方法,并设计了油门/离合器协调控制器和油门/制动切换控制器。试验结果表明,本文提出的方法能合理协调控制汽车驾驶机器人油门、制动、离合机械腿和换挡机械手,实现了车辆的平稳起步,平顺换挡以及对给定车速的跟踪。
According to the road adaptive requirements for the vehicle longitudinal safety assistant system an estimation method of the road longitudinal friction coefficient is proposed.The method can simultaneously be applied to both the high and the low slip ratio conditions. Based on the simplified magic formula tire model the road longitudinal friction coefficient is preliminarily estimated by the recursive least squares method.The estimated friction coefficient and the tires model parameters are considered as extended states. The extended Kalman filter algorithm is employed to filter out the noise and adaptively adjust the tire model parameters. Then the final road longitudinal friction coefficient is accurately and robustly estimated. The Carsim simulation results show that the proposed method is better than the conventional algorithm. The road longitudinal friction coefficient can be quickly and accurately estimated under both the high and the low slip ratio conditions.The error is less than 0.1 and the response time is less than 2 s which meets the requirements of the vehicle longitudinal safety assistant system.
