【作者】 欧洪波；

【导师】 赵燕；

【作者基本信息】 武汉理工大学 ， 机械电子工程， 2006， 硕士

【摘要】 轮胎压力测量是保证汽车安全运行的一个重要因素之一,轮胎性能好坏直接影响到汽车的性能,保持正常的轮胎气压可以提高汽车行驶安全性、改善操纵性能;同时有利于延长轮胎使用寿命,降低汽车使用成本。但由于轮胎是在旋转的运动中,给测量带来了很大的挑战,既要保证测量的精确性和实时性,又要推测出它的变化趋势,为下一步的预测控制做好准备,所以必须要求有很高测量精度和响应速度。 本文就是通过对国内外的轮胎气压实时监测系统(Tire Pressure Monitoring System,以下简称TPMS)的研究,提出一种新型的无源无线轮胎气压监测系统,来解决目前现有系统存在的结构复杂、分辨率低、电池寿命有限、成本高等问题。 声表面波传感器具有无源无线传感的优势,可用于对旋转物体,快速移动等非接触测量。本文研究的是基于声表面波原理的无源无线轮胎压力监测系统,它可以实现高分辨率、小体积、无电池的简化结构。 文章详细介绍了无源无线轮胎压力监测系统中的声表面波传感器工作原理、回波信号组成、数字信号处理和软件开发方法;并讨论了轮胎压力报警模型的建立方法,得到更加接近实际的压力模型;同时还给出了新的系统的硬软件设计方案,最后构造传感器仿真实验平台,进行仿真。主要包括以下内容: (1) 无源无线声表面波传感器系统的构成。分别介绍了延迟型和谐振型传感器的结构和工作原理,并分析了谐振型压力测量系统的构成和工程方法。 (2) 系统激励信号研究。通过分析声表面波谐振器对不同激励信号的响应,本文选用正弦脉冲串作为激励信号,来提高系统工作效率和传感距离。 (3) 建立轮胎压力报警模型。通过对轮胎爆炸的机理分析,得出温度、负载对轮胎的影响,得到更加贴近实际的轮胎压力模型,给出轮胎报警的状态。 (4) 系统主机的设计及系统激励信号和系统电磁兼容的设计。分别选用了MSP430F系列的16位微控制器来进行控制,实现数据采集、激励信号发送、激励信号接收、动态显示、异常报警、数据存储等功能。 (5) 显示和键盘模块的设计。使用液晶显示器(LCD)来显示各个轮胎的状态,时间等信息,并且通过键盘,可以实现系统参数设置等功能。 (6) 对声表面波传感器等效电路模型进行仿真实验。更多还原

【Abstract】 Tire pressure monitoring is an importance factor of guaranteeing automobile safety. The performance of tire plays a directly role of automobile’s performance. Keeping right tire pressure makes automobile to be more comfortable, more safely, more smoothly. It has been proved that tire takes the well-balanced air pressure and the right temperature is very important to the tire life and to cut the using cost. But it isn’t easy to measure the tire pressure because it works at a rolling place. We also should ensure the accuracy and timing tire and to guess the trend for the next forecast control. So the tire pressure measure must be high accuracy and speediness.The paper improve a new passive and wireless tire pressure monitoring system base on the analyses of the existent tire pressure monitor system, which can settle the problem in structure, accuracy, power-life and cost in existent monitoring system.The surface acoustic wave (SAW) sensors can be used to measure parameters of fast moving or rotating objects which are difficult to contact, because of the predominance of wireless passive sensing. The paper studies in passive and wireless tire pressure monitoring system base on surface acoustic wave which can realize small passive and high accuracy in simple structure.The paper introduce the theory of surface acoustic wave sensor, the digital signal treatment, the method of soft design in the passive and wireless tire pressure monitoring system in detail. It also depicts the function of different model in this system. The paper discusses the method of building on the tire pressure alarm model to get a more practical pressure model, and give a new design project about system hardware and to stimuli on the building laboratory platform. Following is the main content of the paper:(1) Structure of the passive and wireless surface acoustic wave sensor system. The paper introduces the structure and the principle of the delay and resonator surface acoustic wave sensor, and analyzes the structure of the surface acoustic wave resonator system and the project measurement.(2)The study on system ignite signal. Through the analysis of the response of resonator base on different pumping signals, sine burst is used for pumping signal of the system to improve the efficiency and detecting-distance.(3)Make up the alarm model of tire pressure. Through the analyses of the tire explosion theory we can know the infection on tire by the temperature and load. So we can build a more practical tire pressure model, and to alarm accurately.(4)Design of the host system part, the sine burst signal and the system Electromagnetic Compatibility. The micro controller is a chip of the 16bits MSP430F series controller. It samples the signal, sends the sine burst, receives the response of resonator, and shows the data in real time, alarms and memories the abnormal data.(5)Design the showing data part. Tire data is showed to the driver by using liquid crystal display (LCD), time is also showed in the LCD. It can change the system setting by a small keyboard.(6) Make a simulation using the building surface acoustic wave sensor model.更多还原