Application of polarized light compass system on solar position calculation

Abstract

In order to satisfy the polarization navigation requirements for the solar position calculation, a new method based on improved polarization angle model by using a three-channel polarization imaging system is proposed. The system consists of three microminiature TFT-LCD optical cameras equipped with three fish-eye lenses, making the structure more compact and smaller. Compared with common method based on spot detection, the proposed method has the advantages of wide field of view and high precision. First of all, the simulation based on optimization algorithm is carried out under different initial values. Then the three-channel polarization imaging system is used to verify the improved polarization angle model in three kinds of weather conditions. The experiment showed that: (i) under clear weather, the solar altitude angle and azimuth errors of the solar position calculated at different times are 0.018° and 0.028°; (ii) in building shelter environment, the solar altitude angle and azimuth errors of the solar position are 0.167° and 0.1°; (iii) in tree shelter environment, the solar altitude angle and azimuth errors of the solar position are 0.921° and 0.25°. Compared with the traditional method, the precision is enhanced at maximum 60.87% by using the proposed method.