Research Of Vehicle Headlamp Light Tester Based On Embedded System

The people are continuously raising their demand about automobile dependability and security with the development of the transport industry. The headlight is an important tool to protect the safe driving of vehicles. The people have paid more and more attention for the performance testing of headlight. The traditional testing instrument of headlight performance has been unable to meet the requirements. It is need to research a new testing system of headlight performance, which is advanced and practical in order to meet the need of the research, design and detection of the headlight.The target of the task is designing a testing system of headlight performance based on embedded system. The testing system is able to collect and process light image information of headlight in real time and show the results of intensity and axis offset. According to the overall needs of system designing, the design scheme based on embedded system was proposed and adopted. The kernel of embedded system is C8051F120 that is full composite SOC. C8051F120 could do well in handling light image information of headlight.The testing system adopts modular design method. System is divided into three parts, which are the testing module of high-beam intensity, the testing module of high-beam declination and the testing module of low-beam declination. In hardware, selection of components is introduced simply and related circuits that achieve collection, communication, storage and display of data are given focused. In software, digital image processing technology, fast median filtering algorithm and edge detection algorithm based on Sobel operator are introduced simply; The test principles of light intensity and light declination and specific implementation of data display and serial communication are narrated focused. In anti-interference, interferences of system are analyzed in detail and several anti-interferences measures in software and hardware are proposed. In standard and test, first of all, tools and environment using in system's standard and test are introduced simply; second, the methods and procedure of system's standard and test are introduced in detail; last, specific test results are given. The using of modular design method, not only greatly shortened the development cycle, but also reduced the cost of research and development and achieved good economic benefit. In the thesis we have done substantial analyses and research to be aware of the headlight testing requirements and traditional testing means. Basing on this and making use of smart camera measurement technology and digital image processing technology, we developed a prototype. Before the prototype was developed, system designing, hardware choosing, schematic and PCB diagram drawing, circuit board making, hardware connection, writing programs, standard and test had to be done. Finally, the performance of an automobile headlight was tested by the prototype. The testing result was contrasted and analyzed with the result that was tested by an existing testing system. The testing results show that the prototype has some excellences such as accurate measuring, high precision, steady performance, convenient using, intuitive result showing and friendly interface. Therefore the testing system has wide application prospects.