A multi-constrained model predictive control ( MPC ) algorithm for trajectory tracking of an autonomous ground vehicle is proposed and tested in this paper. First, to simplify the computa- tion, an active steering l...A multi-constrained model predictive control ( MPC ) algorithm for trajectory tracking of an autonomous ground vehicle is proposed and tested in this paper. First, to simplify the computa- tion, an active steering linear error model is applied in the MPC controller. Then, a control incre- ment constraint and a relaxing factor are taken into account in the objective function to ensure the smoothness of the trajectory, using a softening constraints technique. In addition, the controller can obtain optimal control sequences which satisfy both the actual kinematic constraints and the actuator constraints. The circular trajectory tracking performance of the proposed method is compared with that of another MPC controller. To verify the trajectory tracking capabilities of the designed control- ler at different desired speed, the simulation experiments are carried out at the speed of 3m/s, 5m/ s and 10m/s. The results demonstrate the MPC controller has a good speed adaptability.展开更多
为研究无人车编队系统的编队保持、队形重构及队形变换功能,提出一种混合式领航跟随策略,以降低对领航车的依赖并确保编队完整性。开发基于车间(Vehicle to Vehicle,V2V)通信的跟随车独立避障功能,并设计了实时管理编队成员属性并支持...为研究无人车编队系统的编队保持、队形重构及队形变换功能,提出一种混合式领航跟随策略,以降低对领航车的依赖并确保编队完整性。开发基于车间(Vehicle to Vehicle,V2V)通信的跟随车独立避障功能,并设计了实时管理编队成员属性并支持人机交互的编队节点管理系统。提出一种三维空间下的三次样条曲线动态扩展轨迹规划方法,结合V2V通信获取前车位姿信息生成跟随轨迹并实现避障。利用Frenet坐标系解耦车距保持与轨迹跟踪问题,采用PID控制器和线性二次调节(Linear Quadratic Regulator,LQR)控制器分别进行纵向控制和横向轨迹跟踪。研究结果表明:所搭建的仿真环境可快速验证方法性能,显示该方法具有良好的性能;通过实车验证了车辆编队系统的3种功能,通过车距稳定保持,证实所提方法具备良好实时性,能够实现多车编队的有效跟随,通过多种队形的变换以及成员入队离队场景,显示出高度的智能拓展性和适应性。展开更多
简要介绍了中国列车运行控制系统(Chinese Train Control System,CTCS)的分级,着重介绍了CTCS-2级列车运行控制系统的组成、总体要求、地面设备构成和功能以及车载设备构成、功能和控制模式。CTCS-2级列车运行控制系统的运用,大大提高...简要介绍了中国列车运行控制系统(Chinese Train Control System,CTCS)的分级,着重介绍了CTCS-2级列车运行控制系统的组成、总体要求、地面设备构成和功能以及车载设备构成、功能和控制模式。CTCS-2级列车运行控制系统的运用,大大提高了铁路运营效率。展开更多
基金Supported by the National Natural Science Foundation of China(51275041,61304194)the Doctoral Fund of Ministry of Education of China(20121101120015)the Fundamental Research Funds from Beijing Institute of Technology(20120342011)
文摘A multi-constrained model predictive control ( MPC ) algorithm for trajectory tracking of an autonomous ground vehicle is proposed and tested in this paper. First, to simplify the computa- tion, an active steering linear error model is applied in the MPC controller. Then, a control incre- ment constraint and a relaxing factor are taken into account in the objective function to ensure the smoothness of the trajectory, using a softening constraints technique. In addition, the controller can obtain optimal control sequences which satisfy both the actual kinematic constraints and the actuator constraints. The circular trajectory tracking performance of the proposed method is compared with that of another MPC controller. To verify the trajectory tracking capabilities of the designed control- ler at different desired speed, the simulation experiments are carried out at the speed of 3m/s, 5m/ s and 10m/s. The results demonstrate the MPC controller has a good speed adaptability.
文摘为研究无人车编队系统的编队保持、队形重构及队形变换功能,提出一种混合式领航跟随策略,以降低对领航车的依赖并确保编队完整性。开发基于车间(Vehicle to Vehicle,V2V)通信的跟随车独立避障功能,并设计了实时管理编队成员属性并支持人机交互的编队节点管理系统。提出一种三维空间下的三次样条曲线动态扩展轨迹规划方法,结合V2V通信获取前车位姿信息生成跟随轨迹并实现避障。利用Frenet坐标系解耦车距保持与轨迹跟踪问题,采用PID控制器和线性二次调节(Linear Quadratic Regulator,LQR)控制器分别进行纵向控制和横向轨迹跟踪。研究结果表明:所搭建的仿真环境可快速验证方法性能,显示该方法具有良好的性能;通过实车验证了车辆编队系统的3种功能,通过车距稳定保持,证实所提方法具备良好实时性,能够实现多车编队的有效跟随,通过多种队形的变换以及成员入队离队场景,显示出高度的智能拓展性和适应性。