The Study On Technology Of Steering Coordination Of Articulated Trolleybus

The new double articulated trolleybus has a large capacity and uses clean electric energy with obvious advantages.The design difficulty lies in the flexibility,reliability and stability of the long car body operation.The running performance of the vehicle at the curve directly affects the traffic efficiency and safety.To this end,the following study on the articulated trolleybus steering coordination technology was carried out:First of all,the steering technology and development of the articulated vehicle are systematically sorted out.Explaining the development and study status of steering coordination technology,the evolution process of vehicle steering system,and focusing on mechanical steering and steer-by-wire technology.The relationship between the steering trapezoid and the steering angle of the wheel is studied.Then decided that steering coordination control of the trolleybus is the trapezoid with wire steering.Secondly,the steering motion model of the trolleybus is established.Based on the steering motion of each vehicle unit,the single-axle steering characteristics,four-wheel steering characteristics and scheme of the single-vehicle are analyzed.The derivation proves the angle relationship between the axle of the double-axle trolleybus at low speed steering,and establishes the coordinate sequence of the center of mass of the tractor and trailer axle.When using MATLAB to calculate the steering coordination and non-steering coordination,the towing shaft center of mass is on the rear axle of the tractor.The trajectory tracking,the width of the turning channel is calculated,and the effectiveness of steering coordination is proved.Finally,using Trucksim to establish a dynamic model of the double-hinged four-axle trolleybus including three steering trapezoids,the steering adopts a coordinated control scheme,and the lines are specified according to the standard: circular curve,spiral,"8"-shaped curve,"S"-shaped curve operation.The time domain response graph is obtained;the evaluation items consists of steering stability,steady state and transient response under steering wheel angle input,lateral acceleration,yaw angular velocity,centroid side yaw angle,trajectory offset,and rear magnification factor.The results show that good steering performance can be obtained by using steering coordination control.