基于驾驶模拟实验的山区高速公路运行速度建模

Modeling Operation Speed on Mountainous Freeways: A Driving Simulator Study

摘要:

提出以连续变化的道路上下游设计参数为自变量的运行速度曲线建模方法.研究基于高仿真驾驶模拟实验采集山区高速公路自由流车速，提取运行速度曲线，以当前位置上下游的坡度、曲率、超高和动态视距值为模型自变量，构建通用的运行速度预测模型.模型结果表明路段的平均坡度、平均曲率、最大超高值以及是否存在反向曲线会显著降低当前位置的运行速度，且下游路段越曲折，驾驶员越倾向于提前减速.通用运行速度回归模型的R2为0.74，模型训练集和测试集的预测平均绝对误差均小于3 km?h-1.研究提出的运行速度曲线建模方法充分利用驾驶模拟器高精度速度数据的优势，提供了一种面向连续车速数据的建模思路，验证了通用运行速度预测模型的有效性.

Abstract:

A new modeling approach based on frequent and equidistant speed measurements was proposed. Driving simulation experiments were carried out to collect free-flow speed data on mountainous freeways. Operating speed profile was derived and grade, curvature, super-elevation, and dynamic sight distance variables extracted from upstream and downstream segments were used to estimate a generous operating speed prediction model. Results showed that as the expected, the average grade and curvature of the segment, the maximum superelevation and the existence of reverse curve decreased the drivers’ speed and the curvature differential between the downstream and upstream segment also reduce the speed. The adjusted R2 of the operating speed model was 0.74 and the averaged absolute prediction error for training set and testing set were both under 3 km?h-1. This study took the advantage of high resolution speed data collected from driving simulator and provided a new methodology to model continuous speed data. The results indicated the effectiveness and capability of the proposed modeling strategy.