AntBot, a robot ant capable of navigating outdoors and autonomously, without GPS with only 14 pixels.
AntBot’s objective is to show that it is possible to navigate autonomously outdoors, without using GPS and with very few resources while ensuring precision, robustness and resilience with regard to environmental conditions. This insectoid robot is inspired by desert ants Cataglyphis fortis in many ways respects.
The AntBot robot was developed as part of the thesis of Julien Dupeyroux (2015-2019, ISM – AMU/CNRS) which I co-directed with Stéphane Viollet. AntBot is a 3D printed hexapod robot and totally open-source.
AntBot is equipped with six legs made up of three actuators each and allowing a tripod locomotion similar to that observed in ants. The robot can walk with a maximum speed of 90 cm/s while ensuring a good stability in roll and pitch of the robot head.
Desert ants are sensitive to polarized light from the sky: the dorsal marginal area of their compound eye consists of ommatidia showing sensitivity to polarized radiation of UV light emanating from the sky. This sensory modality was reproduced on AntBot by means of a celestial compass comprising two pixels sensitive to UV light and surmounted by rotating linear polarizing filters. Ventral optic flow vision of insects was also reproduced on AntBot using a minimalist sensor (only 12 pixels) bio-inspired and self-adaptive to changes in brightness: the M²APix (Michaelis-Menten Auto-Adaptive Pixels) sensor.
In order to navigate autonomously, AntBot embeds a navigation system directly inspired by the path integrator of desert ants. This vector and relative navigation mode allows the insect to merge heading information (vision of the polarized light of the sky) and distance information (combination of the ventral optical flow and step counting) to estimate at each moment its homing vector, thus giving the direction, the sense and the distance to be covered to find the nest. This system allowed AntBot to find its way back to the nest with a positioning error of about 5 cm after nearly 14 meters of travel.