Research On Non-signal Pedestrian Crossing Safety Early Warning System Based On Variable Information Sign

There is a difference in the behaviour of motorists towards "yielding to pedestrians",which often leads to accidents in front of pedestrian crossings on non-signal controlled roads where the car in front brakes urgently and the car in the rear avoids and brakes untimely and rear-ends the car in front.The short following distance on urban roads makes the rear driver not in a position to see clearly the warning signs on the road,and the effective observation of pedestrians crossing on both sides of the road is also greatly reduced,which creates a hidden danger to the safety of road traffic,and such rear-end accidents often result in multi-vehicle rear-end collisions with heavy economic losses.Therefore,it is of great practical importance to study an early warning method for motorists at signal-free pedestrian crossings,so that drivers can take early braking measures to reduce the incidence of rear-end accidents.Firstly,pedestrian behaviour and mental processes,modes of behaviour and differences in behaviour at no-signal pedestrian crossings are described,the five levels of pedestrian demand are analyzed,and a critical crossing interval model for pedestrian crossing is elicited through a pedestrian-motor vehicle competition model.Through field surveys,the average pedestrian crossing speed is counted and analyzed to obtain that the average pedestrian crossing speed varies by gender,age and number of people and that the frequency distribution is close to a normal distribution within a certain range.Then,by discussing the advantages and disadvantages of different pedestrian sensing recognition methods,the pressure sensing recognition technology used in this paper is introduced,and its implementation principle is explained in detail.On this basis,a safety warning system based on Variable Message Signs(VMS)is proposed,and the model of the anterior distance of VMS is explained and its range of values is analyzed.The overall composition and control logic of the safety warning system are designed,and the functions of each subsystem are described.Finally,the proposed VMS model is validated by the VISSIM simulation software to realize the simulation in two ways without VMS and with VMS.Motor vehicle flow,average travel time,average motor vehicle delay time,average motor vehicle queue length,maximum motor vehicle queue length and average number of motor vehicle stops are selected as evaluation indicators,and the results of the comparative analysis show that different time periods without accident The results of the comparative analysis show that the road traffic efficiency under different motor vehicle flow conditions is significantly improved after the adoption of VMS deceleration inducement measures in different time periods without accidents.The model proposed in this paper does not have a large impact on traffic queuing and stopping,and can effectively improve road operation speed and reduce the average journey time and average delay while avoiding rear-end accidents.