Research And Development On Cable Force Test System Based On Android Phone Platform

The cables are important components of the cable-stayed bridge, therefore it has very important significance to measure the force of cables for the safety instructions during the construction and the health assessment during the service. Frequency method is one of the most common test methods in engineering practice. With the continuous development in the theory of frequency method and rapid advance in pick-up technology, frequency method has been able to meet the requirements of practical application. However, the traditional cable force test system based on frequency method mostly uses different hardware and software to complete the signal acquisition, signal processing, frequency-domain analysis and cable force calculation. The efficiency of cable force test is not high, also the hardware and software operation require a quite high level of technology which is difficult to grasp for general engineer. Therefore it has an important engineering application value to develop a high-efficiency and easy to operate cable force test system.The main work of this dissertation is addressed as follows:(1) The traditional cable test methods and the current research state of cable force test system is firstly reviewed. Then this paper describes the mainstream mobile phone operating system, the type of phone’s built-in sensor and its application, and the application of android smart device in engineering.It is presented in detail that the method to test the natural frequency of the cable,the method to solve cable force versus frequency and the method to determine the radical frequency of the cable.(2) The concept that developing a cable force test sysytem based on android phone platform is purposed in this paper. Firstly using a mobile phone to acquire the vibration signal of the cable,then applicating the phone’s data processing functions to complete the signal processing, frequency-domain analysis and cable force calculation.(3) Verifying the feasibility of using the phone to pick up the frequency of the vibration signal through the vibration test of simply supported beam in the laboratory. on the basis of the lab’s experiment,we conduct the cable force test in cable-stayed bridge.In the test, wireless acceleration sensor are selected to compare with the build-in acceleration sensor of the phone.The results prove the cable force can be obtained accurately by phone,and through the results comparison, the stability and feasibility of the phone are proved.(4) The development process of the cable force test system is introduced in detail. To meet the needs of cable force test, the system is divided into three modules, namely project management module, cable force test module and data management module.We focus on the design and implementation of each module function.(5) Verifying the cable force test system that is developed in this paper. After verifying the correctness of the system, we take a force test to verify the efficiency of the cable force test system on the the cable-stayed bridge.