Design And Implementation Of Micro CMOS Star Sensor System

Star sensor taking the star as the reference target for attitude measurement and calculation,it is currently the highest pointing accuracy of the sensor,and widely used in space missions.With the development of the spacecraft towards miniaturization,low power consumption,light quality and so on,the traditional star sensor is no longer suitable for the development requirements of the nano-satellite.Therefore,the thesis focuses on the design and implementation of micro star sensor which is suitable for nano-satellites.(1)System describe the imaging properties of CMOS image sensor,carried out the analysis and research to it working principle,performance indicators,and characteristic,determine program of the CMOS image sensor as the star sensor imager.(2)According to the centroid extraction accuracy directly affects the accuracy of measurement for spacecraft attitude.The thesis analysis and research on the current commonly used star extraction algorithm by simulation analysis,and analyzed the subpixel location algorithm for stars,then simulated and analyzed the positioning accuracy affect by stars position noise.The results show that the relative error of the coordinate is within 0.35 pixels,and has better anti-noise ability.(3)According to the two basic mode initial attitude acquisition and star tracking mode of star sensor,and based on analysis of the relevant algorithms,proposed a improve grid algorithm and a fast ROI tracking method.Though simulation to verify the reliability of its.At last,a novel star sensor mode is presented: moon tracking mode,and system analyzed and research to this mode,it is indicated that the moon tracking mode is a feasible star sensor mode.(4)Though the analysis and design of micro CMOS star sensor,developed an micro CMOS star sensor which can directly application on small satellite.The dimensions is 64 mm ?64mm ?82mm,less than 400 g,and peak power consumption below 1W.