Cameras inspired by insect eyes could give robots a wider view

Cameras inspired by insect compound eyes allow an extremely wide field of view without expensive lenses, potentially providing cheap, simple and lightweight visual sensors for navigation or tracking of robots and driverless cars.

Insects like dragonflies have eyes that, in pairs, provide a nearly 360-degree field of vision and help them skillfully escape predators. Their eyes are made up of numerous ommatidia, which are essentially tubes with a simple lens on one end and a basic photoreceptor on the other. Their vision consists of pixel-like inputs from large bundles of these ommatidia.

Creating cameras that can achieve the same thing affordably, either by covering a hemisphere with image sensors or by creating multiple lenses to direct light onto a central sensor, has proven to be a challenge. Now, Zhiyong Fan and colleagues at the Hong Kong University of Science and Technology have replicated the architecture of insect eyes using nanowires made from a crystalline material called perovskite, without the need for of precision-made lenses.

Their design consists of a 3D printed hemisphere approximately 2 centimeters in diameter with 121 apertures, each one millimeter in diameter, which act as a simple pinhole camera. In each hole, a perovskite nanowire directs light from a very narrow field of view directly onto a light sensor, and the electronics combine the results into a single frame. The artificial eye can generate images with a field of view of 140 degrees, and a superimposed pair can extend it to 220 degrees.

Fan says this could be a huge advancement in some robotic applications, such as a swarm of drones flying in close formation. “They have to maintain a distance, maybe a few meters from each other, so they have to know the precise location and the relative speed at which they are moving towards and away from each other,” he says . “So the compound eye is important; it has a wider field of view and also motion sensitivity.

The researchers also built a pair of smaller compound artificial eyes, equipped with 37 light sensors. They equipped a quadcopter drone with this system and were able to use it to track a robotic dog on the ground.

Fan says the compound eye design also has the advantage of being simple, lightweight and cheap, but it won’t completely replace traditional cameras. Instead, he believes the devices will provide additional data useful to robots and other machines, such as self-driving cars.