基于压电薄膜轴传感器的动态称重系统的研发

发布时间：2018-06-04 10:18

本文选题：动态称重 + 压电薄膜　；参考：《合肥工业大学》2014年硕士论文

【摘要】：超限超载现象已严重危害到公路桥梁的安全性和使用寿命。交通部门为了加强对超限超载车辆的管理和实际交通数据的统计，对动态称重（WIM）提出了越来越高的要求。目前市场上运用的动态称重系统均存在过车速度不高，灵敏度差，精度低等诸多问题。而且研究证明，车辆轮迹线在桥梁横断面上的横向位置影响着桥梁的结构行为，是桥梁荷载的一个重要参数。因此，建立一种能识别车辆轮迹线横向位置、灵敏度高的高速动态称重系统，对有效维护重要公路及桥梁的安全运营具有重要意义。本文基于灵敏度高、稳定性好的压电薄膜轴传感器，通过合理设计传感器的布设方式，即首次采用三根传感器以“N”形布设在车道中，研发了一套可检测车辆轮迹线横向位置的动态称重系统。基于Labview的编程平台，设计了系统的分析软件。研发的动态称重系统不仅可以提高动态称重测量精度，还可实现对车辆轮迹线横向位置的检测，也可为交通部门对交通数据的调查提供一种新的简单实用的方法。论文的主要工作如下： 1.详细阐述了压电薄膜轴传感器的压电特性和压电原理，介绍了为保证传感器称重精度，在传感器安装及运用时应该注意的问题。针对环境温度的变化会导致传感器压电常数、体电阻和弹性模量的变化，造成称重结果的误差，提出了温度的补偿公式。 2.考虑到车辆的附加动荷载以及压电薄膜轴传感器的称重特点，提出了优于峰值法的面积积分方法对车辆参数进行识别计算。 3.通过合理设计压电薄膜轴传感器的布设方式，研发设计了一套可识别车辆轮迹线位置的动态称重系统。利用Labview编程语言，对称重系统进行了软件开发，能对采集的信号进行计算得到车辆速度、轴重、总重、轴距、轮迹线横向位置等数据。 4.在实验室设计了试验方案，，验证了所研发的动态称重系统和系统算法的可行性。以黄山市占川河桥为背景，现场试验验证所研发的压电薄膜轴动态称重系统，并详细讨论了系统在现场安装所应该注意的问题。实验室试验和现场试验结果表明，系统具有良好的稳定性和可靠性，精度满足工程要求。
[Abstract]:Overloading phenomenon has seriously endangered the safety and service life of highway bridges. In order to strengthen the management of overloaded vehicles and the statistics of actual traffic data, traffic departments put forward higher and higher requirements for dynamic weighing WIMs. At present, the dynamic weighing system used in the market has many problems, such as low speed, low sensitivity, low precision and so on. It is proved that the transverse position of vehicle wheel track on the cross section of the bridge affects the structural behavior of the bridge and is an important parameter of the bridge load. Therefore, it is of great significance to establish a high speed dynamic weighing system which can recognize the lateral position of vehicle wheel track and has high sensitivity to maintain the safe operation of important highways and bridges. In this paper, based on the piezoelectric thin film axis sensor with high sensitivity and good stability, three sensors are used in the driveway for the first time through the reasonable design of the sensor layout, which is the first time that three sensors are used in the driveway with "N" shape. A dynamic weighing system which can detect the lateral position of vehicle wheel track is developed. Based on the programming platform of Labview, the analysis software of the system is designed. The developed dynamic weighing system can not only improve the measuring accuracy of dynamic weighing, but also realize the detection of lateral position of vehicle wheel track, and also provide a new simple and practical method for traffic data investigation in traffic department. The main work of the thesis is as follows: 1. The piezoelectric characteristics and piezoelectric principle of piezoelectric thin film axis sensor are described in detail. The problems that should be paid attention to in the installation and application of the sensor in order to ensure the weighing accuracy of the sensor are introduced. In view of the error of weighing result caused by the change of ambient temperature, piezoelectric constant, bulk resistance and elastic modulus of the sensor, the compensation formula of temperature is put forward. 2. Considering the additional dynamic load of the vehicle and the weighing characteristics of the piezoelectric thin film axle sensor, an area integral method which is superior to the peak value method is proposed to identify and calculate the vehicle parameters. 3. A dynamic weighing system which can identify the position of vehicle wheel track is developed and designed by reasonably designing the configuration of piezoelectric thin film shaft sensor. By using Labview programming language, the symmetrical weight system is developed, which can calculate the vehicle speed, axle load, total weight, wheelbase, transverse position of wheel trace and so on. 4. The experimental scheme is designed in the laboratory to verify the feasibility of the developed dynamic weighing system and system algorithm. Based on the Jinchuan River Bridge in Huangshan City, the piezoelectric film shaft dynamic weighing system developed in the field test is verified, and the problems that should be paid attention to when the system is installed in the field are discussed in detail. The results of laboratory and field tests show that the system has good stability and reliability, and the precision meets the requirements of engineering.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U492.321

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