Design Of Body Network System Based On CAN/LIN Bus Technology And Reliability Analysis

In recent years, automotive technology increasingly develops to electronic, intelligentdirection, and the proportion of automotive electronic control system of the vehicle is growingday by day. The increasing of automotive electronic improves the comfort of the vehicle. Butit also causes great difficulties of body wiring; electromagnetic interference is increasinglyserious as while. So the use of bus technology which reduces body wiring to improve thesafety and the comfort of the vehicle is the inevitable trend. The main work of this paper is toanalyze the reliability of the network system of the body hardware design, software designand systems.First, the hardware designs of the body network system include:Topology design: the using of CAN/LIN mixed network designs the body structureof network topology, shows the characteristics and advantages of the CAN bus andLIN bus fully, the maximum reduction of costs is based on the system reliability.The gateway node module design: ECU using low-cost embedded FREESCALEMC9S08DZ128CAN micro controller chip. Its internal integrated CAN controllerand SCI module with low cost, convenience and other advantages. It provideshardware resources for the CAN/LIN network design.Power Module Design: use LM317as the primary device voltage conversion. It has avoltage of1.2V-37V output range, and can provide more than1.5A of current drive.It provides a stable and reliable power supply support for the system.Floor control module design: ECU selection of the underlying low-cost microcontroller MC9S08MP16; Motor drive using H bridge power driver chip MC33887which with current feedback, short circuit protection and under-voltage lockoutfunction; Lights drive using N-channel FET power tube BTS6143D, remove therelay sparks and other security risks.Second, the software design of the body network system：SAE J1939protocol as the reference, and CAN2.0B specification、LIN2.0specificationas the standard, Design the body of the application layer protocol network system with usingthe idea of modular. And separately design the software for lights, windows, locks and mirrors.Implementation of user-friendly design such as intelligent switch control, anti-trap windows,central locking, automatic lock/latch functions.Three, reliability analysis of the body of the bus system:Gateway node-bus system, lights and door node reliability analysis were carried out.Focuses on the reliability of electronic equipment from the perspective of each modulereliabilities expects the mean time to failure is expected module, and proposed solutions foreach module.In this paper, automotive CAN/LIN bus technology conducted in-depth research andanalysis. And "special vehicle multiplex system research and development" as the basis of research projects completed body network system hardware design, software design andfunction of the body’s electrical control system implementation and testing.