Study On Portable Vehicle Performance Test System Based On GPS

With the development of automobile industry and the popularity of vehicle used in people's lives, automobile performance test technology and its application are constantly updating and improving. Now, the test technology is achieved mainly through indoor test bench experiment and outdoor road test. During the test, on the one hand, professional test equipments and platforms are required, on the other hand, professional persons are needed to operate these equipments and analyze test results.therefore,it is quite professional. Unfortunately, the test equipment is expensive, bulky and complicated to operate. these factors inevitably give great limitations to automobile performance test. Meanwhile, due to the complexity of the participants and the increase of car accidents, more and more users want to have a basic understanding of their car's performance, for example, the performance of braking and driving power. It is useful to improve the safety and decrease the occurrence of accidents. Car users also hope that they can understand the change of their car's performance at anytime and in anywhere.In order to get accurate motion states during driving, this paper studies on Portable Vehicle Performance Test System based on GPS. The test system is able to measure the important physical parameters and it is convenient to take, easy to use and cost a little. It uses GPS signals as basic parameters to calculate and analyze the basic vehicle physical parameters, which is free from the influence of environment and space. This study is based on GPS signal reception module, MCS-51 minimum development system and CH375 U disk storage module. The test system achieves GPS signal acquisition and handling timely. It can calculate and analyze the important physical parameters such as vehicle speed, track and distance with the help of the related algorithm, display these parameters timely by LCD screen and store the data by U disk.Firstly, GPS measurement principle and MCS-51 basic knowledge are introduced in this paper. The points are the GPS coordinates conversation principle as well as MCS-51 related knowledge. Secondly, this paper analyzes and explains the hardware of the developed vehicle performance system. A comprehensive introduction is given to the GPS receiver module HOLUX M-87, MCS-51 minimum development system and CH375 U disk storage module. Then, Keil C is used to code vehicle performance system software which is the most critical part in the paper. It mainly consists of three parts. Part one is about the programming of GPS signal reception procedure and MzT24 LCD screen display procedure. Part two is about the programming the software of acceleration performance,braking performance,coastdown performance and track record procedure. Part three is about the programming of the storage of the experiment data. Finally, in order to verify the accuracy and reliability of the developed test system, vehicle road tests are carried out in the mentioned conditions. In the process of experiments, vehicle performance is tested with portable test system and commercial test system AM-2600S simultaneously and then detailed analysis and comparison are given according to the results.The comparison shows that the portable test system can fulfill the required basic funtions such as displaying vehicle dynamic performance, recording vehicle track and testing braking performance, driving power performance and coastdown performance. Its accuracy is approximal to the commercial test systm AM-2600S. Meanwhile, the portable test system uses conventional electronic equipment and components, which has dominant influence on the cost. It is also easy to use, simple to operate, convenient to carry. The test system is of practical value.