Optimization Research On Real Time Performance Of CAN Bus In Automobile

With the growth of the amount of the vehicle electronic devices and increasinginformation need to be exchanged between the devices, it would not be conducive tolightweight and cost reduction of automotive if still using the traditional point-to-pointharness connection. Also the reliability and coordination between the modules alsodeteriorate, the on-board networks was put forward with this demand. By the comprehensiveperformance analysis, CAN is currently the most widely used in automotive communication.It’s high reliability, real-time and relatively reasonable prices make it still have bestapplication prospects in autobody, chassis, and power train of vehicles.How to provide a safer and more reliable traveling environment to passengers is theprimary consideration in the design of a car, among various factors, the design of the entirenetwork plays a great role. The shorter frame structure, non-destructive arbitrationmechanism based on the priority and error detection mechanism can largely guaranteereal-time communication and reliability, but taken into account that the increase of messagecongestion and interference caused by the increase of future automotive electronicequipment, how to further optimize the network is necessary to solve the problem.Chapter3provides several methods for optimization, listing the algorithms in appendix.The real-time optimization includes offset optimization, optimization of message priority,message bit stuffing optimization and multi-signal package; the reliability optimizationincludes calibration in data field, data redundancy, and openning WatchDog Timer. Theoptimization algorithm is integrated into a software, by comparison to currently availableopen software, it has unparalleled advantages, for it supplys several optimization and morereasonable parameter calculation. Then the paper gives the validation of the optimizationprocess to illustrate the effectiveness of the optimization method. Verification ECU has a certain degree of driving ability, and can be directly used as a automotive CAN networknode. Finally, make a summary of the thesis and put forward inadequacies, and give somesuggestions to follow-up work.