Flash-based Spaceborne High-speed Large-capacity Storage Technology

The data recorder is one of the key equipments on spacecraft, used to capture,record and on-board process the datum of space experiments or detection. With thedevelopment of astrionics, mass Solid State Recorder (SSR) based on FLASHMemory has been one of the dominating solutions for the storage of mass data on thespacecraft.This thesis is funded by 'Key Technique Research of Payload Integration ofMoon Rover', a sub-project of 'Key Technique Pre-research of Moon Rover'. Thetarget of this project is to research and realize a hardware and software system ofhigh-speed mass Solid State Recorder on spacecraft, based on FLASH Memory, withmass capacity, high-speed, nonvolatility, and low power dissipation. The system canmanage the datum similar to a file management system, and the system structure willbe standardized and modularized, which can suit for various requirements.The development trend of international SSR technique on spacecraft and therequirement of future space flight projects of our country are analyzed first. Secondly,the SSR unit scheme, according to the character of the moon rover payload integratingelectronic system, and then the process of hardware & software design and debugging,are introduced. Finally, The scheme to be improved based on the forenamed project isdiscussed.Kinds of innovative and key technique are involved in this project. 1) Busparallel expansion and pipeline technique are adopted to improve the average inputand output speed of recorder based on FLASH memory. 2) A concept of 'cluster' isintroduced. The using state message of each cluster is loaded in the spare area,following the target datum, to keep the pipeline sequence of multiple clusters' loading,which guarantee the average input speed of system. 3) Based on the using statemessage of every cluster, the Cluster Allocation Table established in memory enablethe system to manage the recorder flexibly in high speed, similar to a file managementsystem. 4) PowerPC 8245 based embedded system, along with Vxworks real-timeoperating system is introduced to make the system more easier to be applied to theprojects in the future.The fruit of this thesis establishes a firm foundation for the actual developmentof FLASH memory based SSR used on spacecraft and is very useful for reference.