A Bio-Inspired Navigation Strategy Fused Polarized Skylight and Starlight for Unmanned Aerial Vehicles

The migratory animals are capable of traveling long distances by fusing varied information, such as the halteres, the star positions, and the polarization pattern. Motivated by the navigation strategy of migratory animals, a bio-inspired navigation strategy based on polarized skylight, starlight, and halteres is presented in this paper. To enhance the environmental adaptability of the polarization navigation system, a sun vector calculation method tightly fusing the degree of polarization (DoP) and the azimuth of polarization (e-vector) is proposed. By setting the threshold of DoP values of the observation points, the DoP and the e-vector within the threshold range can be selected to deduce the sun position. As such, the robustness and reliability of the sun position can be improved. Concerned with the issue of attitude and heading determination in GNSS-challenged conditions, an integrated navigation strategy combined with polarized light and starlight is proposed. In addition, a Kalman filter is adopted to fuse the navigation data of polarized light, starlight, and inertial sensors. Finally, simulations are conducted to validate the performance of the integrated model. The results illustrated that the proposed navigation strategy is capable of determining the attitude and heading in the scenarios of which the Global Navigation Satellite System (GNSS) is disturbed.