CAR-Auto Body CAN Bus Control System

I. Introduction CAN Bus CAN Bus German Bosch company Hyundai Motor in order to solve the many control and test equipment and data exchange between the development of a serial data communication protocol. It is a multi-Main Bus, communications medium can be Twisted-pair, coaxial cable or fiber optics, communication rates up to 1 Mbps, range up to 10 km. CAN one of the greatest feature of the agreement is the abolition of the traditional address coding and replaced by blocks of the communications data encoded so that the number of nodes in the network theoretically unlimited. The CAN bus error correction capability has strong support differential transceivers, thus suitable for high-interference environment, and have a longer transmission distance. Therefore, the CAN protocol for distributed measurement and control many areas very attractive. With IC SCM in the car and the wider use of the car more and more electronic control modules, automotive electric bus has become the vehicle of an inevitable trend. Not only can be used to simplify vehicle bus Harness, what is more important is to increase the variety of intelligent function. If the fault detection and voice alarm, and so on. Second, the CAN bus automotive applications At present the car at the main network connectivity using two CAN, a drive system for the high-speed CAN, the rate reached 500 kb / s; Another Body System for Low Speed CAN, the rate is 100 kb / s. CAN drive system is the main target of linking engine controller (ECU), the ABS controller, airbag controllers, combination instrument and so on, they are the basic characteristics of the same, with vehicle traffic control are directly related to the system. CAN main body system connectivity and control of the car inside and outside lighting, light signals, wiper motors and other electrical appliances. At present, the drive system and the body system CAN CAN two independent bus design between the "gateway" to achieve in all resource-sharing between the CAN and data bus all the information back to the dashboard display. Motorists only have to look at the dashboard, one can know whether the various electronic control devices normal work. Third, the Shanghai Tongji car with McNair Technology Co., Ltd. CAN Bus Body Control System With McNair car body CAN Bus CAN bus control system through the body to control electrical appliances, such as cars external lighting, light signals, wiper motors, washing motor, speakers, start motor, after the defrost heater, require lock actuators, fuel tank cover lock actuator, the window of a car after endoscopy and other devices. The entire control system can be used combination of centralized and scattered control mode. A master module, as well as several voice from the control module in the control module. From the control module controlled by the specific number of how many decisions. Generally control module can be divided into before and after control module, glass movements control module, electric rearview mirror control module, electric sunroof control module and electric seat control module. In addition to the main control module boxes around, since several other modules into systems and through LIN bus communication with the main control module to achieve various control functions, such as voice in the control module through LIN bus from the main control module to read all kinds of fault information to the voice of the driver and sends the information sent to the maximum security lock the car Control module for landing and taking off of the glass and read electric sunroof, lock car in the midway achieve glass skylight and the shut down automatically, but also electric mirrors and windows of the centralized control switch signal transmission through the LIN bus to the controller to achieve the corresponding control. Each module implementation of the specific power relay device can be used or intelligent power device, a smart power devices can reduce the volume control box, and has over-current, short-circuit protection and interrupted feedback, and other functions. System integration of fault detection and alarm functions and voice remote control, anti-theft features, and enhanced vehicle control of the intelligent, humane, simplify vehicle Harness, improve electric system reliability. Foundation framework: the basis of the framework of the entire system from the main control module, the front modules, car module consists of a total of three. Body control of the majority of its electrical, functional diagram, see the basic framework. Fourth, the Shanghai Tongji body with McNair Technology Co., Ltd. advantage CAN Bus System (1) simplification of the whole power supply system to facilitate electrical wiring Because of the change in control method and the use of the electronic switches, relays and canceled most Fusing silk. Vehicle Harness reduced by 20% to 40% (engine line essentially unchanged, the former Wai line reduced by 20% to 30%, the bottom line by 30% to 40%). (B) The safe and reliable performance Intelligent electronic modules used in the relay switch replaced, the drive to achieve non-contact, reduce electromagnetic interference, and extended service life. Since the return module used within the fuse to replace the fuse wire, with overload protection and automatic recovery functions. Fault diagnosis can be conducted, alarm and records. Electric is to ensure the reliability of the vehicle, and enhanced maintainability. Such as: filament url will remind drivers to replace. Switches send signals to the main control module through the current very low switching (mA level), significantly extend the service life of the switch. (C) Intelligent Control Add in the minimal hardware can be achieved where many intelligent functions. For example, the software can be realized through the headlamps delay shutdown function, does not have the automatic shutdown after defrosting actuator increase delay shutdown function, and can be detected battery voltage and low-voltage alarm automatic shutdown with high-power electrical function. Add a light sensor can achieve automatic control headlamps function. (D) highly scalable Every addition of a new electrical appliances, automobiles Harness must re-development. Using CAN bus, the new appliances can be easily articulated in the system, the need to change only a small amount of Harness. (5) simplify the production process and reduce the cost of production The bus system configuration flexibility, easy expansion, when modified to increase electrical appliances or vehicles, and only a small amount of software changes and Harness. Even in the development of new models, as long as doing a small amount of change also. (Vi) lower maintenance, maintenance costs The bus system onboard fault detection, alarm and recording functions, the vehicle electrical system maintenance and repair is very convenient. Vehicle plants can reduce maintenance personnel training and the purchase of equipment and other costs. V. Development Status and Prospects Overseas, the vehicle bus technology has been basically formed a unified standard hardware interface has been unified, chip has been established, mass production. Many of the current domestic automotive electronics manufacturers in the development of CAN bus system, all products are rolled out. For China, and it is a car-bus sunrise industry, has boundless prospects; Believe bus system in China would not be long before universal application.