Design Of Infrared Measurement System For Determining The Relative Position Of Inner-formation Gravity Satellite

The Inner-formation satellite measurement system is used to measure the relativeposition of the Inner-satellite in the Outer-satellite. Its measurement results areimportant data to invert the Earth’s gravity field by Inner-formation Flying System (IFS).The Inner-satellite measurement system has to ensure an accuracy of1mm and ameasuring frequency of10Hz according to the mission requirements, and meet therequest that the interfere acceleration with the pure gravitational orbit on theInner-satellite is less than10-10ms-2. Based on the analysis of the mission requirementsand the interfere forces restraining, this paper focuses on the design of a suitableinfrared measurement system. The major work and conclusions are as follows:(1) In the mission analysis of relative position measurement system, infrared imagingsystem parameters and the light path of the measurement system are designed.According to the imaging environment and measurement precision requirement, asuitable infrared detector is selected and the corresponding lense paremeter is given out.According to the location precision requirement, the cavity configuration and cameralayout are designed. A detailed analysis of the cross locating precision is carried out, soas to determine an optimized optical path configuration scheme(2) An uncooled infrared camera for the measurement is studied. The imaginghardware circuit design includes low noise power supply, precision bias voltages, ADconversion, high speed clock, sampling timing and output interface design.The infraredimage processing method includes nonlinear correction, contrast enchancement,binarization, image filtering, edge extraction and circle center picking.(3) According to the overall design scheme, the satellite cavity structure is processdand a real measurement system is built. Based on the actual layout parameter, the crosslocating algorithm is analyzed and a redundancy backup strategy is put forward. Thetest results verify that the proposed measurement system can meet the requirement ofaccuracy and real-time.