| The abnormal tire pressure is an important factor affecting the vehicle driving safety,the fuel economy and the ride comfort.The negligence of the driver about abnormal tire pressure often make that the lives and property of people caused enormouslosses.Early warning of tire pressure anomaly is very necessary.At present,the TPMS on the market are mainly concentrated on premium vehicles.The tire pressure monitoring devices of medium and low-grade economy cars owns a huge market.In view of abnormal tire pressure monitoring,a tire pressure monitoring system based on CAN bus technology is proposed.Firstly,the hardware circuit is designed,including the selection of single-chip microcomputer,the minimal system design of single-chip microcomputer,reset circuit design,crystal oscillator circuit design,power conversion circuit design,CAN communication module design,LED drive circuit design,buzzer drive circuit design,PCB design.Then the software system design,mainly including the introduction of program editing software,the main program flow design,dormancy module design,self-learning module design,tire pressure calculation module design.Based on the moving average filter algorithm,the abnormal tire pressure can be judged and the driver can be reminded to check the tire pressure in time by the acoustooptic warning device.The test results show that,When the tire pressure is lower than the manufacturer recommended tire pressure of 75%,the tire pressure monitoring system will be able to determine which tire is leaking after one minute,it has high practicability and accuracy. |
