Study On The Key Tecltnology Of Bus Precision Docking System

Rapid growth of automobile quantity has resulted in road traffic congestion, environmental pollution, traffic safety and other issues. The Bus Rapid Transit (BRT) of large capacity and high transport efficiency is considered to be one effective way to solve the problem of urban traffic congestion.Vehicles precision docking technology is a key technology to improve the operation efficiency of the BRT. If a bus cannot be secured for a precision docking, it will force the driver to waste a lot of time to adjust the bus and increase the parking time which will reduce the operation efficiency of the BRT and cause inconvenience to passengers on and off. Vehicles precision docking technology is one of the key technologies of CVIS (Cooperative Vehicle Infrastructure Systems) and can be applied to achieving the bus precision docking function. That function can enhance the operation efficiency of the BRT and reduce the fatigue strength of the drivers.Specifically for the bus precision docking system, the main tasks of this paper are as follows:(1) This paper analyzed the functions, system architecture, performance indicators, operation principles, the key points, operation modes and system implementations of the bus precision docking system.(2) A precision docking system based on the microcontroller MC9S12XS128is designed and a smart model car is used to further the development of the system. Hardware and software system are designed. The hardware system design includes power modules, electromagnetic sensors, distance marker detection circuit, motor driver module, speed detection module, steering module, the wireless communication module, human-computer interaction module. And the software system design includes system flowchart, MCU initialization, and model car control algorithm.(3) Experiment and debug were carried out on the precision docking system using a model car under laboratory conditions. Results demonstrated that the model car can perform precision dockings in the lay-by and meet function requirements of the precision docking system. Realization of the precision docking system laid foundations for the further research.