Development Of Three-dimensional Small Angle Measuring Instrument Based On Temperature Compensation

Angle detection technology in the field of precision measurement has important significance.In order to study the effect of the magnetic field in space on the bending degree of the extension rod of the star sensor,it is necessary to carry out the precise measurement of the three-dimensional small angle.Due to the small installation and measurement space of the satellite and the strong electromagnetic interference and temperature changes in the measurement environment,the existing three-dimensional angle measurement method can not measure the three-dimensional bending small angle of the star-sensitive sensor extension rod with high precision,and even damage the instrument.In order to solve this problem,firstly,this paper analyzes the application of the autocollimation principle in 3D angle measurement,and puts forward the 3D small angle measurement algorithm combined with three-dimensional space angle synthesis and decomposition theory.Secondly,based on the principle of optical autocollimation theory and two-dimensional PSD principle,the focal length,resolution and magnification of the optical system are calculated based on the design objectives.On the basis of this,the optical devices are selected and the optical autocollimation system is designed.Based on the theoretical design of three-dimensional small-angle measuring instrument,the hardware circuit design of three-dimensional small angle measuring instrument is introduced,including PSD conditioning circuit system and embedded measurement and control system,and the software is designed.According to the requirements of the design objectives,the three-dimensional small-angle measuring instrument needs to work in the environment with severe temperature change,and the PSD has non-linearity and so on,which influence the measurement precision of the small angle measuring instrument.So the temperature-angle compensation model is established based on the experimental results..Finally,the calibration experiment is carried out on the small angle measuring instrument and the measurement error is calculated.Three-dimensional small angle value is calculated according to the three-dimensional small angle measurement algorithm.The experimental results show that the three-dimensional angle measuring instrument proposed in this paper has the advantages of anti-interference and high precision,and its working precision is 0.24 arcsecond.The method is mainly applied in the field of three-dimensional angle measurement with narrow measurement space,strong electromagnetic field disturbance and intense temperature change.It basically meets the requirements of three-dimensional angle measurement under small space conditions,such as stable and reliable,high precision,strong anti-interference ability and so on.