Study On The Predicting Model For Operating Speed On Combined Sharp Horizontal And Vital Curves

In modern society, drivers are believed to be responsible for many traffic accidents, withone of the primary causes being drivers’ miscalculation of vehicle speed. One of the mainreasons for the miscalculation is the unreasonable limits for driving speed on the road.Therefore, it is feasible to predict the safe driving operating speed by studying drivers’ speedcontrol mode on different roads, which is helpful for the improvement of speed limiting andthe road capacity, further to lower road traffic accident rate.This paper, viewed from the system of driver-vehicle-road, comprehensively analyzes driver speed control behavior mode at combined sharp horizontal and vital curves,and a prediction model for driver speed control is built according to drivers’ behaviorcharacteristics.Firstly, the maximum security speed of different vehicles at the target road section isanalyzed and calculated based on the vehicle dynamics theory.With the drivers’ speed control behavior as research object, road test experiments arecarried on along some sample section on the upstream section of Xi’an-Hanzhong highway.On one hand, by studying the speed change status when some certain driver drives the car, themajor road alignment factors is analyzed which directly affect the driver’s speed controlbehavior; on the other hand, through the analysis for distribution character of feature speedofdifferent vehicles on certain curve-ramp section, speed control behavior mode of differentvehicle drivers is summed up.Finally, according to the driver speed control behavior mode and its influencing factors, afuzzy speed predicting model with5inputs&5outputs is established via Matlab. The resultsof this model include speed control behavior of different vehicle drivers and the operatingspeed at the beginning, the middle and the end spot of curve-ramp section.Through the experiments, the establishment of fuzzy forecasting model with the testresult error than smaller, and actual driving conditions are identical, and fuzzy forecastingmodel of result not more than for the calculation of the safety speed range, and the results show that the model in the practical application process is feasible, and has certain use value.