Research On Computer Redundancy Design Of UUV Control System

As people demand more and more high for the performance and function of UUV, the work environment of UUV is becoming more and more complex, so we should ensure the UUV has higher reliability. Because of the redundancy technology can effectively improve system reliability, and has been widely used in unmanned aerial vehicles at home and abroad and the flight control computer system. However, its application in the UUV is still rare,mainly because of UUV strictly restricted by size, weight and so on. Therefore, applied the redundant technology to UUV control system computer is still a challenging research topic.This paper studies the redundancy technology which can satisfy the high reliability system as the basic foothold, designs a kind of TMR (Triple Modular Redundancy) motion control computer system which can applied to the UUV control system.According to the actual needs in the present and future of UUV control system, based on the redundancy design principles of motion control computer system, we studied and designed the computer redundancy system overall scheme from redundancy structural design,hardware design, communication design and software system. Combining the structure characteristics of TMR motion control computer system and operating mechanism of the system, putting forward that implementing the design scheme from three aspects, such as the redundancy management of system, system reliability and safety analysis and the experiment of TMR motion control computer system.For the system redundancy management, we proposed the redundancy management scheme based on the design principle of redundancy management scheme; In the scheme, for the task synchronization problem of redundancy system, we designed the task synchronization scheme, in which based on task detection point synchronization algorithm, which can realize the initialization synchronization, input synchronization and output synchronization of redundancy system. We designed the heartbeat detection algorithm based on the processor fault and the compare monitor detection algorithm based on the output interface fault. For the output vote of redundancy system, we proposed an improved vote algorithm based on history information of "three choose two" and designed the vote algorithm flow chart of redundancy system working in triple double modular redundancy and double modular redundancy.This paper assesses the reliability and safety of TMR motion control computer system to verify the rationality of the design scheme. By establishing a Markov state transition model,we can get the reliability and safety expression of TMR motion control computer system.Then for the three important parameters of the expression: failure rate, fault coverage and system running time, assuming that the failure rate is a constant, we analyze and compare single computer reliability and TMR motion control computer system reliability in different fault coverage. We also analyzed the changing rule of the system's reliability and safety in different fault coverage and system running time.This paper designs the fault simulation experiments to verify the feasibility of design scheme,in which the TMR motion control computer system was used in the steering control to verify the feasibility of redundancy design scheme, fault detection algorithm and vote algorithm.