轨迹-速度协同控制的山区公路平面线形设计方法

Method for Horizontal Geometry Design of Mountainous Roads Based on Trajectory-speed Cooperative Control

为了减少因人-车-路三者不协调引发的行车事故,使公路设计尽可能反映真实的公路行车特点,提出了一种新的公路平面线形设计方法。根据初步的线位方案计算可使用路幅的几何边界,预测典型方向控制模式的行驶轨迹,再以轨迹曲率为基础预测典型速度控制模式所对应的行驶速度,最后同时用轨迹和速度对几何要素进行控制,该方法特点是半径、转角、回旋线、弯间距、偏转方向和路宽等几何要素均能够为设计者所调整。结果表明:由于设置了多种驾驶模式,并在轨迹-速度决策时引入了车辆性能、行驶稳定性和舒适性限制,该方法更贴近公路的设计思想,尤其适用于起伏地形的中低速公路平面线形设计;运用该方法,设计人员还可以调整除了半径之外的几何要素来实现道路设计的一致性。

In order to reduce traffic accidents caused by incoordination of driver-vehicle-road system,and to make highway design reflect the driving characteristics as truly as possible,a new design method for horizontal geometry design was presented.Firstly,determined the trajectory of a typical driving mode after calculating the geometric boundary of the pavement that driver could use according to the preliminary alignment layout.Then,determined the speed of a typical driving mode based on the curvature of the trajectory.Finally,used both the trajectory and the speed to control the design values of the road elements.The important property of the improved new method was that curve radii,deflection angles,spirals,tangent lengths,deflecting directions and road widths all could be modified by practitioners.The results show that the method is closer to the design philosophy due to the setting of various driving patterns,and the restrictions on driving stability,comfortableness and dynamic performance in determination of trajectory and speed,and it is especially good for horizontal geometry design of low-speed roads in wavy terrains.By using the proposed method,practitioners can adjust more road elements as well as curve radii to achieve consistency of road geometry design.