Author:
F. J. Smith
Affiliation:
School of Electronics, Electrical Engineering and Computer Science, Queens University, Ireland
Keyword(s):
Polarization, skylight, navigation, insect vision, POL, insect celestial map, robot, drone.
Related
Ontology
Subjects/Areas/Topics:
Biomedical Engineering
;
Biomedical Signal Processing
;
Physiological Processes and Bio-Signal Modeling, Non-Linear Dynamics
Abstract:
Many insects can navigate accurately using the polarised light from the sky when the sun is obscured. They navigate using two different types of optical features: one is a set of three ocelli on the top of the head and the second is a celestial compass based on several photoreceptors on the dorsal rims of the compound eyes. Either feature can be used alone, but the dorsal rim receptors appear to be more accurate. Robots have been built that navigate using three photoreceptors, or three pairs of orthogonally oriented photoreceptors, but none has been designed which uses a full set of photoreceptors similar to those in the dorsal rim. A new model of the function of the dorsal rim compass is proposed which relies on the four azimuths at which the polarization angle χ = ±π/4. A simulation shows that this could provide an accurate navigational tool for a robot (or insect) in lightly clouded skies.