Research On Hydraulic Braking System Of Container Automatic Guided Vehicle

China’s trade volume ranks first in the world,port transportation is the main transportation route of trade exchanges,with the increase of trade volume year by year,the size of port cargo throughput is a key factor affecting the amount of trade.In order to cope with the growing demand for goods,the development of smart ports has become a top priority,smart ports through the Internet to achieve efficient operations,smart port unmanned guided transport vehicles are an indispensable part,it needs frequent braking and docking in the precise position of running goods,so the container automatic guided vehicle braking system for the efficiency of terminal cargo operation has a close relationship,and even affects the incoming and outgoing volume of the entire port.The purpose of this paper is to propose an electro-hydraulic proportional braking system that can meet the braking pressure requirements of unmanned heavy-duty vehicles.The electro-hydraulic proportional braking system realizes the braking action of the vehicle by receiving the braking intention of the upper controller,and the lower controller outputs the expected pressure of the brake wheel cylinder,and the system pressure responds quickly and accurately.Firstly,The characteristics and principles of container AGV by-wire electrohydraulic brake system,the working principle and characteristics of proportional brake valve and brake wheel cylinder are introduced.The proportional brake valve and brake wheel cylinder are built in modules,and the model of the electro-hydraulic proportional braking system is built in the AMESim simulation software.Incremental PID and fuzzy PID algorithms are designed for wheel cylinder pressure,and the pressure simulation analysis of brake wheel cylinder is carried out in the joint simulation environment of AMESim and Simulink.And the longitudinal control strategy of the whole vehicle is designed,one is the brake deceleration control algorithm of feed-forward + feedback;The second is the LQR braking distance control algorithm.In Truck Sim,the dynamic model of container AGV is built,and the simulation and analysis of the longitudinal control algorithm can better realize the longitudinal braking of the vehicle,and the pressure response of the electro-hydraulic proportional braking system can also meet the braking requirements.Finally,the accuracy and rapidity of the pressure response model are verified in the bench test in the laboratory,and the accuracy of the longitudinal braking algorithm is verified in the test prototype vehicle test,The electro-hydraulic proportional braking system proposed in this paper is applied in traditional heavy-duty vehicles to meet the needs of large braking pressure and improve the rapidity and accuracy of braking pressure.In addition,the system can also be used for braking control of new energy vehicles and intelligent unmanned heavy-duty vehicles,as the basis of the upper control of intelligent vehicles,improve the safety of road traffic,promote the efficiency of port operation,and have good application prospects in vehicle braking.