针对无人汽车车队在附着系数较低的路面上行驶的纵向控制问题,提出考虑道路附着系数和本车无法持续获取前车加速度信息的最小安全车距的计算方法,以此来对传统的期望车间距的恒定时间间隔(Constant Time Gap,CTG)算法进行改进.然后,采...针对无人汽车车队在附着系数较低的路面上行驶的纵向控制问题,提出考虑道路附着系数和本车无法持续获取前车加速度信息的最小安全车距的计算方法,以此来对传统的期望车间距的恒定时间间隔(Constant Time Gap,CTG)算法进行改进.然后,采用分层的结构设计队列控制系统,并通过对车队的队列稳定性进行分析,得出上层控制中的控制器增益的取值条件.最后,对一个由4辆车组成的车队进行仿真验证.结果表明:提出的改进恒定时间间隔算法可以在路面附着系数较低的情况下保证车队的队列稳定性,同时能够避免相邻两车间发生碰撞.在本车无法获取前车加速度信息且前车紧急制动的情况下,采用改进的恒定时间间隔算法的车队在行驶过程中的最大车间距偏差率为19%,低于应用传统方法时的最大车间距偏差率22.27%,且车间距误差随着时间的增长最终收敛至零.采用改进的恒定时间间隔算法的车队在行驶过程中车辆的加速度的最大值为0.75 m/s^(2),低于利用传统方法时的加速度的最大值0.91 m/s^(2),说明改进的恒定时间间隔算法可以保证车队的稳定行驶,并且具有较好的乘坐舒适性.展开更多
Due to unreliable and bandwidth-limited characteristics of communication link in networked control systems,the realtime compensated methods for single-output systems and multioutput systems are proposed in this paper ...Due to unreliable and bandwidth-limited characteristics of communication link in networked control systems,the realtime compensated methods for single-output systems and multioutput systems are proposed in this paper based on the compressed sensing(CS)theory and sliding window technique,by which the estimates of dropping data packets in the feedback channel are obtained and the performance degradation induced by packet drops is reduced.Specifically,in order to reduce the cumulative error caused by the algorithm,the compensated estimates for single-output systems are corrected via the regularization term;considering the process of single-packet transmission,a new sequential CS framework of sensor data streams is introduced to effectively compensate the dropping packet on single-channel of multi-output systems;in presence of the medium access constraints on multi-channel,the communication sequence for scheduling is coupled to the algorithm and the estimates of the multiple sensors for multi-output systems are obtained via the regularization term.Simulation results illustrate that the proposed methods perform well and receive satisfactory performance.展开更多
文摘针对无人汽车车队在附着系数较低的路面上行驶的纵向控制问题,提出考虑道路附着系数和本车无法持续获取前车加速度信息的最小安全车距的计算方法,以此来对传统的期望车间距的恒定时间间隔(Constant Time Gap,CTG)算法进行改进.然后,采用分层的结构设计队列控制系统,并通过对车队的队列稳定性进行分析,得出上层控制中的控制器增益的取值条件.最后,对一个由4辆车组成的车队进行仿真验证.结果表明:提出的改进恒定时间间隔算法可以在路面附着系数较低的情况下保证车队的队列稳定性,同时能够避免相邻两车间发生碰撞.在本车无法获取前车加速度信息且前车紧急制动的情况下,采用改进的恒定时间间隔算法的车队在行驶过程中的最大车间距偏差率为19%,低于应用传统方法时的最大车间距偏差率22.27%,且车间距误差随着时间的增长最终收敛至零.采用改进的恒定时间间隔算法的车队在行驶过程中车辆的加速度的最大值为0.75 m/s^(2),低于利用传统方法时的加速度的最大值0.91 m/s^(2),说明改进的恒定时间间隔算法可以保证车队的稳定行驶,并且具有较好的乘坐舒适性.
基金supported by the National Key Research and Development Plan(2018YFB1201601-12)。
文摘Due to unreliable and bandwidth-limited characteristics of communication link in networked control systems,the realtime compensated methods for single-output systems and multioutput systems are proposed in this paper based on the compressed sensing(CS)theory and sliding window technique,by which the estimates of dropping data packets in the feedback channel are obtained and the performance degradation induced by packet drops is reduced.Specifically,in order to reduce the cumulative error caused by the algorithm,the compensated estimates for single-output systems are corrected via the regularization term;considering the process of single-packet transmission,a new sequential CS framework of sensor data streams is introduced to effectively compensate the dropping packet on single-channel of multi-output systems;in presence of the medium access constraints on multi-channel,the communication sequence for scheduling is coupled to the algorithm and the estimates of the multiple sensors for multi-output systems are obtained via the regularization term.Simulation results illustrate that the proposed methods perform well and receive satisfactory performance.
