【作者】 李凯；

【导师】 李波；

【作者基本信息】 武汉理工大学 ， 控制理论与控制工程， 2007， 硕士

【摘要】 随着我国人们生活水平的提高，汽车拥有量迅猛增长，随之而来的行车安全问题也更显突出。在汽车高速行驶过程中，轮胎故障是所有驾驶者最为担心和最难预防的，也是突发性交通事故发生的重要原因。汽车轮胎压力监测系统(简称TPMS)主要用于在汽车行驶中实时监测轮胎状态，预防轮胎爆胎。本文结合国内外现有TPMS发展现状及发展趋势，从系统低功耗与小体积特性角度出发，设计与开发新的轮胎压力监测系统。根据系统的性能指标与功能要求确定了TPMS总体方案，对目前TPMS研究过程中遇到的几大难题如信源编码方式、轮胎定位技术和节能问题等分别提出了相应的解决方案：针对TPMS系统的特点，为TPMS系统选用一种采用群同步法的新型编码方式，消除了产生直流分量的可能，解决了收／发端同步困难的问题；分析了原有的几种轮胎定位技术在实际应用中存在着明显的不足，提出一种新的轮胎识别技术，使得轮胎的识别更简单有效；对发射模块的各部分电路在不同工作模式下的能耗问题进行了详细的分析，在此基础上实现软件对能耗的管理。选择基于MEMS技术集成的压力温度传感器MPXY8020A、具有睡眠模式的AVR单片机Atmega8L作为微处理器和采用SAW稳频无线发射电路达到发射模块低功耗、体积小、重量轻的目的。为了与发射电路相匹配，采用超再生接收电路，通过Atmega8L自带的USART串口和在RS485标准接口中广泛应用的由美国MAXIM公司生产的MAX1487芯片来实现接收部分与人机接口部分间的数据传输。在人机接口部分对系统的工作状态作了细致的划分，给出不同工作状态下的显示、报警与操作表。人机接口部分接收到数据以后经过分析处理，根据工作状态将温度压力数据或其它数据送数码管显示，当压力异常变化、温度压力数据过限或发射模块故障时提供不同的声光报警信号，提醒驾驶员采取必要的措施，同时驾驶员可以根据实际情况设定温度压力数据阀值，文中给出相应的硬件设计原理图和详细的软件流程图。更多还原

【Abstract】 With the improvement of living standard in our contry, the amount of automobiles increases rapidly, and the subsequent the auto-safe problems are becoming more prominent. During the high speed driving, the tires’ troubles, which can be hardly prevented, are the drivers’ chief worry, and these troubles are also the main factors of the sudden traffic accidents. While automobile is working, Tire Pressure Monitoring System (TPMS) is used to monitor real-timely the tire status preventing tire burst. This thesis is mainly concerned with the system improvement about low-powered and little volume speciality at the base of overseas existing TPMS, and developed the new TPMS.Considering the performance indices and function requirements of this TPMS, the overall scheme is put forward, this thesis proposes a solution in a number of challenges encountered in the process of researching TPMS: Group-synchronization eliminate the DC component and solve the problem of admission / originator synchronization difficulty; Analyze the shortcoming of the original tire identification technology and presents a new tire identification technology, which makes the program more simple and effective; Analyze energy consumption of the transmitter’s circuit, then the principle and realization of the software energy management for the sensors is introduced.Chooses MPXY8020A based on MEMS technology integration as temperature pressure sensor, Atmega8L as Microprocessor and SAW fired frequency stabilization circuit for the purpose of low power, small size and light weight.Uses chaozaisheng receiver circuit to match transmitter, realizes data transmission between receiver and man-machine interface with chip MAX1487 producted by American MAXIM Corporation.Given detailed delineation of system state in part of the man-machine interface, and then given data show, alarms and operation table in different state. Man-machine interface receives signal and display the data of air-pressure and temperature on the screen for drivers. If air-pressure or temperature becomes abnormity, the system will give alarm for drivers, drivers have enough time to take some measures.更多还原