A novel hyperacute gimbal eye to implement precise hovering and target tracking on a quadrotor

Abstract

This paper presents a new minimalist bio-inspired artificial eye of only 24 pixels, able to locate accurately a target placed in its small field of view (±10°). The eye is mounted on a very light custom-made gimbal system which makes the eye able to track faithfully a moving target. We have shown, that our gimbal eye can be embedded on a small quadrotor to achieve accurate hovering with respect to a target placed onto the ground. Our aiborne eye was enhanced with a bioinspired reflex in charge of locking efficiently the robot's gaze onto a target and compensate for the robot's rotations and disturbances. The use of very few pixels allowed to implement a visual processing algorithm at a refresh rate of 400 Hz. This high refresh rate coupled to a very fast control of the eye's orientation allowed the robot to track a target moving at a speed up to 200°• s −1 .

A bio-inspired sighted robot chases like a hoverfly

“…On the robotic side, it was established here that only 23 pixels part of a vibrating artificial compound eye was able to locate a robotic target with hyperacuity and to pursue it with great accuracy. Compared to a previous study [44], we obtained a similar linearity in the target localization within a much larger visual range and without the need of a complex calibration process. The robot's orientation and its distance from the mobile target were precisely estimated under various lighting conditions.…”

“…Recent studies featuring hyperacuity, i.e. 'locating features with a greater accuracy than that corre sponding to the resolution imposed by the photoreceptor's limited pitch' as defined by [42], have focused on the processing of the amplitude of the photosensor's output signals to locate an edge/bar using only two pixels [43], to locate and track a white cross using complex calibration process [44] or to measure robot 1D egomotion [45]. The visual sensor is a vibrating artificial compound eye called Active CurvACE (i.e.…”