带启停巡航功能的全速自适应巡航控制是研究自动驾驶系统的基础。提出了一种分层控制方法实现全速巡航功能:上层控制器基于线性二次型最优控制的车辆自适应巡航控制系统;并在该系统之上分析启停巡航控制的运动特征,对车辆起步时的加速度进行修正,改变控制器的参数,实现了启停巡航控制;设计了一种启停巡航功能和ACC平滑过渡的方法;下层控制器来实现上层控制器的期望加速度。采用车辆动力学仿真软件Carsim与Matlab/Simulink联合仿真并将控制逻辑编写为C语言代码然后下载至实车控制器进行实车试验,试验结果与仿真结果表明所设计的控制器既能满足启停巡航控制平稳起步与制动停车的要求,同时满足高速ACC的较小跟踪距离误差和速度误差,证明了所设计控制器的有效性和实用性。
Full-Speed Adaptive Cruise Control (F-ACC) with Stop and Go is the foundation of automatic driving. A hierarchical control strategy is adopted to design F-ACC. The upper controller is based on the Linear Quadratic Regulator (LQR) theory. The acceleration of vehicle when the vehicle start has been modified and the parameters of the controller have been changed based on the analysis of movement characteristics of the Stop and Go control. The lower controller has been designed to realize the desired acceleration of the upper controller. A smooth transmission method between Stop and Go control and ACC has been designed, which can not only satisfy the demand of gently start when performing Stop and Go, but also achieve small distance error and velocity error in high speed ACC. The co-simulation of Carsim and Matlab/Simulink is used to test the effectiveness of the designed controller. Then the control logic has been written by C language and downloaded to the Electronic Control Unit (ECU) for real vehicle test. The real vehicle test results are similar to that conducted in computer simulation, which proves the controller is effective and practical.