Research On Early Warning System For Monitoring Tire's Pressure And Temperature Of The Vehicles

TPMS is one of the most important safeguards for vehicle to safely drive. With the high speed development of the Auto Electronic Technology and people's more demands for safety, it would be of widely application foreground to research and design the TPMS, and meanwhile, it would also bring more social benefits and economical benefits.The paper have deeply analysed the development status and direction of TPMS and compared the difference between Indirect TPMS and Direct TPMS. The paper choose Direct TPMS as research object, Direct TPMS uses the sensors to measure the pressure and temperature of the Tires (including voltage of the battery) and transmits them to the monitor which is installed in the driving platform by radio frequency modulation. The monitor displays all kinds of preferences of the tires in time and, when the preferences is abnormal, the alarms will works automatically and display related information.The system's alarm exactly, reliability and promoting the battery life are the technical difficulties or the key point for Direct TPMS. Regarding these points, several aspects are studied:1) Studying and Designing the RF Transmit detailedly, including the Matching Network for Antenna, the wireless communication protocol and the management of RF transmission.2) After insuring the accurate probability of wireless transmission, the paper researches and advances the arithmetic based on Sensor Fusion in order to avoid the TPMS giving wrong alarm.3) Analyse the application electromagnetism environment of TPMS and design the hardware and software concretely by considering the performance of EMC.4) Besides choosing the lowest power consumption IC, in design, chooses the Li/SOC12 battery as the power supply and uses a more effective manage method to reduce the system's power consumption.5) The information sharing, based on CAN Bus, is fully considered and designed.By test, after taking these methods listed on the front, can effectively improve precision and veracity of the system, and at last, the design carried out the anticipative target.