Study On Reliability Based On The Technology Of Redundant Of CAN Bus

With the expansion of the CAN bus application field, its reliability has beenacquired more attention. For some special applications, the general CAN bus systemcould hardly meet the requirement of reliability. The most effective method to solvethe problem of reliability of CAN bus using in the harsh condition is adoptingredundancy. Using redundant technology can complete the weak part of CAN noderedundancy backup so that to improve the reliability of the system.This paper summarized the hardware fault of CAN bus which was defined in theCAN bus protocol. It analyzed and simulated the influence of the fault to CAN busand CAN bus node. Meanwhile, it listed the causes of the CAN bus fault andproposed the corresponding preventive measures according to the cause of theproblems. It provided the method of how to choose redundancy scheme based onexperience and the modeling, then analyzed the key issues of fault recognition andswitch. It eventually achieved the goal of improving the reliability of CAN bussystem by testing. The main research content of this paper is as follows:(1)It summarized the definition of CAN bus fault which was in the CAN busprotocol, analyzed and observed the influence of the fault on the CAN bus. Then itanalyzed the causes of fault and proposed the corresponding preventive measuresbased on CAN bus protocol specification ISO11898and CAN2.0.(2)It analyzed the pros and cons of different redundancy schemes and providedhow to select redundancy schemes based on the principle analysis and modeling.Then it analyzed the fault identification methods and designed the process of theredundancy switch.(3)It selected the components to design the redundant CAN node hardwarecircuit and software program, built the experimental platform and simulated CAN busfaults to verify the rationality, correctness and feasibility of fault identification andredundant switching principle, and to verify that the redundant CAN bus system canavoid failure of the system caused by hardware fault, and can achieve the purpose ofimproving the reliability of CAN system. The purpose of this paper is based on the research of the redundancy CAN bus,provides the general design idea of redundancy CAN bus network, It has certainguiding significance to the design and application of the later complex of CAN bussystem.