Vehicle Comfort Systems CAN Bus Network Simulation

Growing contemporary automotive electronic technology, more and moreelectronic control unit is arranged into relatively small car, in orderto all of the electronic control unit is connected together into a network,while as little as possible encroachment occupants of the space, and thedata and information can be transmitted to the sharing manner, one canmeet the multiplexed bus communication system is essential, CAN bus isa bus communication system. At present, it has been widely used in vehiclepower and network communication and network control systems of the body,and maturing.New models in the research and development stage, the number of carelectronic control unit as the vehicle design requirements and marketpositioning are very different from the research and development coststo consider, the research and development personnel and cannot be testedto the actual vehicle network only by the car’s CAN bus network simulationto observe the feasibility of each node of the network design. GermanyVector has developed a network integrated development environment CANoe,is used to simulate the car’s computer network. By using the software thatcomes with the communication protocol defined tools CANdb++to define thenetwork topology, ECU attributes, semaphores, message structure,transceiver relationship, timing, and detection consistency generated.DBC file. CAPL (CAN Access Programming Language) language (which is aprogramming language similar to the C language) on a single node and thewhole network is defined by CANoe software comes with the definition andtesting of simulation, but also of the external environment.The car comfortable and system design is based on high-end sedancomfort system expanded, including automatic headlights, automatic wipers, electric seats, smart entry system, and so on high-end vehiclecomfort systems. Design by using CANoe software design comfortable CANbus network simulation, including the body control module, door controlmodule, car comfort system control module and so on.1. Functional designThrough the analysis of the various functions of the vehicle comfortsystems, the number and function of the entire system modules to be divided.This comfort system roughly divided into three parts, including bodycontrol module, door control module and control module. Detailed divisionof the following ways:（1） Body Control Module1(BCM1): control of the front of the vehicleaccording to the lights, turn signals; cleaning windscreens andheadlamps; horn; hood switch; trunk door switch; fuel cap switch.（2） Body Control Module2(BCM2): control of the rear of the vehicleheadlights, turn signals; heated rear window; rear window sunshade;reversing signal.（3） The Front Door Control Unit (FDCU): into the Driver’s side DoorControl Unit (DDCU) and the front Passenger side Door Control Unit(PDCU), the control of the driver and co-pilot windows; outside rearview mirror adjustment; seat and mirror position memory; doorlights; central locking and so on.（4） The Rear Door Control Unit (RDCU): into the Rear Left Door Controlthe Unit (RLDCU) and Rear Right Door Control Unit (RRDCU), controldoor locks and power windows.（5） Other control unit: Passive Entry Passive Start system (PEPS);Driver’s side Seat Control Unit (DSCU); Park Distance Control(PDC).2. Software DesignVehicle comfort systems CAN bus network topology design; detaileddesign of each control module used in the control area network communication protocol; using the CAPL language of the nodes in thenetwork modeling, the node is able to handle bus messages environmentvariables, error frame, keyboard operation or timing interrupt loadedinto a network simulation environment, and establish a good model; takeadvantage of the database editing tool CANoe CANdb++definition database,the establishment of the comfort CAN bus network system as a wholesimulation environment.3. SimulationsThe CANoe come Panel editor to create the control panel of the CANbus, you can control the message value, configuration variables, overallmanagement, and so on. To modify the message value of the control panelin the message value node simulation run. The monitoring controllerrunning state; CAN bus network monitoring and statistical frequency ofvarious types of message frame transmission, the bus load, the controllerstatus; graphical manner, showing signal changes within the period of time.More intuitive that a common analysis through multiple signal responseanalysis charts displayed in text-message time stamp, channel, ID, name,data and other information in a time domain signal changes.4. SummariesResearch and development staff can help shorten the time as much aspossible, through the modification of the control functions for differentnodes and different levels of vehicle design vehicle CAN bus network wouldbe able to increase and delete nodes, a sophisticated vehicle CAN busnetwork simulation. The design of the simulation environment forreal-node test vehicle network testing lay the foundation.