Study On Principle Of Automatic Gearshift System Of Car And Development Of Control System

With the development of economy, car is commonly used in our daily lives. It gives us convenience, meanwhile car is also a hidden killer. A lot of live lost in the traffic accident. As known to all, one of the major causations is tiredness driving, so how to reduce the negative effects and make gearshift easier and comfortable to control is a critical issue for a designer to deal with. This subject makes an improvement which is based on the original gearbox. By using the Electronic Pneumatic shift system, it can achieve the properties of fast response, easy control, reduction in operation without losing the original gearbox's merit of high efficiency, low coast, and simple structure. This system can reduce the working intensity of the drivers. Further more, less accident would happen. So it has important theory and application value to study on this subject.The whole system is made up of the control system and the execute system. They communicate between each other by CAN Bus. When the driver gives the order to shift gears, the control system collects and analyzes the signals of the shaft's position, then get the order of gearshift which is sent through the CAN Bus by the MCU P87C591 which has a can interface. The driver can choose P,R,N shift by the shaft, but in the voluminous time, car work on the automatic shift. The system give the different gearshift law in the good,bumpy,ice road condition ,it make the law pertinence. The driver only need control foot-fishing to make the car speed up or down. So the drivers' working intensity is reduced greatly.This system makes an improvement in gearshift operation ,accelerograph control and clutch control. It can reduce the drivers' working intensity and is easier for the mender to repair it with the application of CAN Bus. CAN Bus communication can meet the gearshift control system's strict restriction in realtime and reliability for its excellent error correct mechanism, reliable and higher baud rate in data transmission. The system is reliable, efficient and fast in response to gearshift control. It is also cheaper in manufacturing cost.