基于多级前瞻式仿真的公交串车防治方法

公交串车是高频公交线路上常见的系统运行失效现象。由站间行程时间和站点停留时间不确定性引起的串车现象集中体现了公交系统的不稳定性。为了防治公交串车,提出了一类将公交车在站点滞留适当时间的控制方法。新方法基于公交线路仿真系统中多级前瞻式控制行为的演化来确定最佳控制行为。为了合理度量线路运行稳定性,并建立有效的控制行为代价函数,分别定义期望系统车头时距和动态环线车头时距。给出了利用滚动时域法将实地数据用于估计路段行程时间和站点乘客登车时间期望与方差的具体方法。数值算例验证了上述串车防治方法和控制行为代价函数的有效性。研究表明新方法不仅可以有效防止高频线路上串车现象的发生,也可有效减少乘客的平均候车时间。

An approach to resisting bus bunching based on multistage look-ahead in a bus line simulator

Bus bunching is a phenomenon related to inefficient system that often appears in a high-frequency bus line. Bus bunching embodies the instability of bus system due to the uncertainty of travel time and dwell time of buses. To resist this undesirable bunching, we propose an approach to determining the appropriate slack times used to hold buses at stops. The holding strategy bases on looking ahead multiple expected actions in a bus line simulator. The impact of the expected actions is measured in two different ways including the expected system headway and the dynamic circle headway. The field data will be used to estimate the means and variances of travel time on road segments and boarding time at stops in a rolling-horizon way. Numerical experiment is used to verify the approach and the chosen estimate of the cost of action. The result demonstrates that the approach can effectively eliminate bus bunching on a high-frequency bus line and effectively reduce the average waiting time of passengers.