The Research On Integration And Application Technology Of Satellite-borne Microgravity Scientific Experiment System

Based on the background of SJ-10 satellite,this paper discusses in detail on research of integrated design technology of various types of satellite-borne microgravity scientific experiment system based on data management and process control,with maximum utilization of space,weight,energy and other resources provided by the satellite platforms and ensuring the integrity and adequacy of scientific experiments as the design principle,to guarantee the effectiveness of scientific achievements.The starting point of technological research and the idea of engineering implementation are to fully aim at scientific objectives and to satisfy the requirements of the principles,methods and means of scientific experiments.In the process of development,innovative exploration and implementation of various technological routes are carried out,and the key technologies of complex model and process control and mass information flow management of large space microgravity scientific experiment system are solved under strong engineering constraints.The main innovation points of this research include: Firstly,the low-cost RS485 bus physical layer interface is applied in the field of aerospace for the first time in China,which realized the system network communication based on self recognition mode of instructions and data,and the network node can choose FPGA,dedicated protocol chip,embedded software and other means to achieve network communication UART link layer protocol and application layer protocol with high reliability;Secondly,according to the distinguishing feature of SJ-10 satellite mission,the payload management subsystem takes LOONGSON CPU,Orbita memory chips and other high performance chips which are made in China as core devices to achieve a highly integrated design of its functional module,and the adopted support and management technology of multi-payload experimental devices is in the domestic leading level in the miniaturization design area,at the same time,it has made active exploration and laid a solid foundation for a large number of orbital applications of domestic high-performance core devices;Thirdly,the system level fault isolation and redundancy design are carried out for the reliability weaknesses of the commercial off-the-shelf(COTS)products,moving parts and pipelines,which are used by a large number of payloads.The SJ-10 satellite has made a complete success in launching,operating and recycling,and valuable recycling samples and large amounts of scientific data were obtained.The results of the sample and data analysis show that the scientific task has also been a complete success,thus proving the correctness and reliability of the payload system design.According to the statistical analysis of the results and experience of scientific experimental payloads on SJ-10 satellite,more than 95% of the scientific data are image and video data,especially for materials and life sciences experiments,there are still a considerable number of microscopic images.In the process of space experiment,because of the lack of real-time teleoperation,image quality control and data compression and transmission of mass data become the key points and difficulties in the management and control of the experimental system.The single pixel camera for super-resolution imaging using compressed sensing theory can solve the dual problems of imaging quality and data reduction,therefore,the future application of single pixel camera to space microgravity experiment and even other space image acquisition domain is analyzed and the key technologies are studied in advance in this paper.The main innovation points of this research include: Firstly,the sub-Rayleigh imaging technique of sub-scanning sampling is proposed by using compressed sensing algorithm,and the results are verified by experiments.By using only 6.25% of the total pixels of the images,super resolution images exceeding the system resolution are obtained.In addition,sub-sampling can reduce the sampling time,which has important significance for real-time observation;Secondly,this paper proposes a threshold method to increase the signal-to-noise ratio of compressed sensing imaging which perform image reconstruction by using only measurement data with larger absolute values,and the results are verified by theory and experiments.Compared with the traditional compressed sensing imaging,it can improve the quality of reconstruction and reduce the reconstruction time at the same time.The research direction are super-resolution imaging and de-noising,and achieved satisfactory results in the ground experiment.Furthermore,the research on miniaturization,integration and high reliability of single pixel camera has been carried out,so that single pixel super-resolution imaging can be applied in future space experiment system.