Robots Evolution: Adopting Eyes of a Fly

Robots with flies' eyes could take advantage of the insect’s vision system to better locate the edges and boundaries of objects. This ability could help robots perform a variety of tasks more quickly and accurately than if they were using traditional sensors enhancing unmanned vehicles, guided missiles, and high-speed industrial inspection robots to locate tiny, moving objects with high precision.

Researchers from the Naval Air Warfare Center in China Lake, California, and the University of Wyoming have developed a fiber optic sensor inspired by the compound eye of the common housefly, Musca domestica. Flies possess a visual precision beyond the resolution limit – a property called hyperacuity. This feature is actually common to many animals, including humans. Overall, insect vision (and sensor technology inspired by it) is still far inferior to human vision. Unlike conventional image processing systems which are often digital, the fly’s processing system is analog. The analog system helps the fly extract edge information much more quickly, and also enables parallel processing. Both these features contribute to the fly’s highly accurate, high-speed vision system.

The researchers explained that the more interesting component of the fly’s vision system is that the field of view of each photoreceptor in a fly’s eye overlaps with those next to it, with up to 90% overlap. Each eye contains about 3,000 ommatidia – the major structural unit of the eye – and each ommatidium contains eight photoreceptors. The photoreceptors’ main function is to convert light into ionic current, which then goes to the fly’s processing system(s).

The researchers designed their sensor to mimic the fly’s overlapping photoreceptors and analog, parallel processing system. The sensor consists of a 1-mm-diameter ball lens that focuses light onto an array of photodetectors, where the field of view overlaps by about 70%. In experiments, the sensor could locate a 1-mm-wide string as the string moved across the field of vision at distances up to 200 mm from the lens, with minimal error.

Posted by Jason McManus.