针对交通系统的动态性和随机性,提出了信号交叉口的自适应控制模型。充分考虑了转弯比例的时变性以及车道分配的时变性,给出一种交叉口随机动态模型。将强化学习(RL)引入到交通信号系统中,针对交通网络的交通流及信号特征,建立了RL的状态空间、动作空间和回报函数,以最小化交叉口的排队车辆数为目标,实施对交通信号的优化控制.在不同的交通环境设定下,对典型的十字交叉口进行仿真试验,将RL控制方法同传统的定时控制和感应控制进行了对比。结果表明,RL控制器具有很强的学习能力,对于交通环境的突然变化仍可以保持较高的控制效率。
On account of the random, dynamic fluctuation of traffic demands, an adaptive control model of signalized intersection was proposed. The traditional intersection traffic model was extended to a new mode taking some real aspects of traffic conditions into account, such as the turning rate and the lanes scheme. Moreover, a stochastic traffic signal control scheme, based on Reinforcement Learning, was introduced in the traffic signal control systems due to its powerful adaptability. The model was tested on a typical four-legged signalized intersection under the various scenarios, and compared to both pre-timed controller and the actuated controller. Analyses of simulation results using this approach show significant improvement over traditional control, especially for the uncertain change of the traffic condition.