Micro-nano Satellite High Reliability Star Computer Fault-tolerant System Design

With the development of spaceflight technology and the diversification of space missions,nano satellites with low cost,high functional density,short development cycle and flexible launch mode have become new hotspots in spaceflight.As the control center of the satellite,it's need to put forward higher requirements for the reliability of the house-keeping computer system.Using the fault-tolerant way to effectively improve the reliability of the house-keeping computer has become the focus and hotspot of the current aerospace research.In this paper,based on the deep analysis and research on the design method of the house-keeping computer architecture at home and abroad,and combining the characteristics of the nano satellite,a high reliability house-keeping computer architecture for nano satellites based on triple modular redundant fault tolerance is proposed.The system is based on the hardware voting mode,using three independent homogeneous single machine running at the set point of voting data,and then output data.Hardware voter through the hardware description language integrated in the FPGA,achieves the task synchronization,data voting,interface expansion,fault detection and other functions.Based on the hardware fault tolerance design,in order to improve the reliability of data transmission between single computers,firstly,it adopts the multi-bus structure based on CSP protocol;Secondly,it adopts NVP technology and RB technology to fault-tolerate some programs;Then,it adopts ED AC technology,refresh mechanism and data backup methods to fault-tolerant data storage of different types of storage devices respectively.Finally,we classify the faults and propose recovery methods for different fault types.At last,the paper designs the prototype of house-keeping computer with redundancy of three modules,analyzes and validates the reliability of the system.Through reliability theory analysis and prototype reliability test experiment,the results show that the system can significantly improve the reliability of the house-keeping computer.