FREQUENCY DOMAIN CHARACTERIZATION OF OPTIC FLOW AND VISION-BASED OCELLAR SENSING FOR ROTATIONAL MOTION

Abstract : The structure of an animals eye is determined by the tasks it must perform. While vertebrates rely on their 2 eyes for all visual functions, insects have evolved a wide range of specialized visual organs to support behaviors such as prey capture, predator evasion, mate pursuit, flight stabilization, and navigation. Compound eyes and ocelli constitute the vision-forming and sensing mechanisms of some flying insects. They provide signals useful for flight stabilization and navigation. In contrast to the well-studied compound eye, the ocelli, seen as the second visual system, sense fast luminance changes and allow for fast visual processing. Using a luminance-based sensor that mimics the insect ocelli and a camera-based motion-detection system, frequency-domain characterization of an ocellar sensor and optic flow (due to rotational motion) is analyzed. Inspired by the insect neurons that make use of signals from both vision-sensing mechanisms, complementary properties of ocellar and optic flow estimates are discussed.