  Inspired by many insects, several polarized skylight orientation
determination approaches have been proposed. However, almost all of these
approaches always require polarization sensor pointing to the zenith of the sky
dome. So, the influence of sensor tilts (not point to the sky zenith) on
bio-inspired polarization orientation determination needs to be analyzed
urgently. Aiming at this problem, a polarization compass simulation system is
designed based upon solar position model, Rayleigh sky model, and hypothetical
polarization imager. Then, the error characteristics of four typical
orientation determination approaches are investigated in detail under only
pitch tilt condition, only roll tilt condition, pitch and roll tilts condition
respectively. Finally, simulation and field experiments all show that the
orientation errors of four typical approaches are highly consistent when they
are subjected to tilt interference, in addition, the errors are affected by not
only the degree of inclination, but also the solar altitude angle and the
relative position between the Sun and polarization sensor. The results of this
paper can be used to estimate the orientation determination error caused by
sensor tilts and correct this kind of error.
