Design Of Advanced Front-Lighting System Based On In-Vehicle Network

Lamps'low beam as a traditional road driving lighting, it could work only in one mode which is exactly an immovable light shape. But the actual road surrounding and driving condition are extremely complex, for example road corners, devious roads, the difference highness of roads, number of the passengers, luggage load and speed up-down changing. That's why the topic, traffic-safety became a big problem. With the auto electronic technology developing, the requirements from people of driving in the night are raising up. So, at the beginning of the century, the more humanly system-Adaptive, Frontlighting System(AFS) became the most of famous car makers'investigation favor which can match the requirements much better.Recent years, the application of auto bus technology gets more attention and it is widely used in order to predigest auto-body wiring. Base on the combination of bus technology and AFS, this article investigates the topology network, hardware and software design of AFS with bus mode. And a complete AFS which based on CAN bus is designed in my article.This article introduced the beginning, developing and application status, then I analyzed the constitution, function and work theory. After the development of auto-body network nowadays was introduced in detail, the AFS based on CAN bus was designed. The module of data collection-process, motor drive, CAN communication and failure diagnostication-process are including in the system. In the section about hardware, there are sensor module, power model, controller circuit, motor drive module, failure check circuit and hardware protection circuit. In the section about software, there is a whole system flow including basic program, application program, arithmetic program and so on, all above realized a complete auto-body communication system.From the AFS test result, we got the conclusion that this system can realize not only up-down and left-right adjust control but also failure diagnostication function. So all of these make sure to provide drivers the best lighting in many kinds of conditions (speed up, speed down, upgrade, downgrade, turn direction and failure mode), and help to avoiding dazzle as well. The result of the test also shows us the feasibility and correctness of the design. The whole system can reach the requirements of ECE R48 for lighting.At the end of the article, there is summarize for the topic, there are also some questions which haven't solved yet, I think they could be the ideas for improving the system in the future.