<a></a>The angle of the polarization (AOP) and the degree of polarization (DOP) of the scattered skylight are symmetrically distributed concerning the solar meridian. Based on the symmetry of the skylight polarization distribution pattern, this paper proposes a novel skylight orientation sensor consists of a camera, an S-waveplate, and a linear polarizer. The skylight orientation sensor is using the image polarization encoding capability of the S-waveplate and the linear polarizer to convert the skylight polarization information into the image’s symmetry
axis extraction, which has the advantages of no resolution loss and
instantaneous field of view error. The symmetry axis in the image is consistent
with the solar meridian. Therefore, the angle between the solar meridian and
the skylight orientation sensor reference axis can be obtained without
calculating the polarization information, which is also beneficial for
real-time performance. The angle measurement accuracy and uncertainty of the skylight
orientation sensor are verified by numerical
simulation and outdoor experiments. The results demonstrate that the skylight
orientation sensor has good application potential in autonomous navigation.