| Data bus technology is a means of communication widely used in aerocraft control system. CAN bus is hotly studied at home and abroad because of its high performance, low cost and other characteristics. But when it is used in the field of aviation, there are two major problems. One is the system's real-time communication, and the other is its reliability. Focusing on the two problems, this thesis makes a study of the control system of the Incorporate Space Vehicle, in which the real-time capability and reliability of CAN bus is analyzed, and the simulated platform of the control system is designed and valilated.Firstly, the constitutes and signal transmission characteristics of the control system are analyzed. According to the deep analysis of the real-time capability and reliability, the conclusion is that the basic CAN bus cannot satisfy the two performances in the field of aviation. For the disadvantage of basic CAN protocol, in combination of research results of CAN bus real-time capability and reliability made by domestic and foreign scholars, a project combined a default identifier distribution and time-triggered mechanism is researched to resolve the problem of real-time capability. As for the reliability, the commonly used redundancy technique is chosen. By comparing the advantages and disadvantages of different degree redundancy methods, CAN bus controller redundancy is the best method to improve the reliability of the system without affecting real-time capability. Finally, the simulated platform of the control system is designed, and CANoe is used to analyze and assess the simulation results on the platform.Simulation results show that the project combined with the default identifier distribution and time-triggered mechanism can effectively solve the problem of network real-time capability under the high bus load. The method of CAN bus controller redundancy can detect errors and switch to another bus in a timely manner, which greatly improves the reliability of the system.
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