Tianjin University develops bionic compound eyes to create 3D positioning systems for self-driving cars

According to foreign media reports, scientists have recently invented a bionic compound eye that can help scientists understand how insects use their compound eyes to quickly perceive objects and their movement trajectories. In addition, this compound eye can also work with cameras to create a 3D positioning system for robots, self-driving cars and drones.

(Photo source: Tianjin University)

Researchers at Tianjin University in China say they have developed a bionic compound eye that not only looks like an insect's eye, but also works like one. A compound eye is made up of hundreds to thousands of identical eyelets, each of which is an independent light-sensing unit.

"Imitating the insect vision system tells us that unlike the human vision system, which uses precise images to detect the trajectory of an object, insects detect the trajectory of an object based on the intensity of the light emitted by the object," said a member of the research team. "This motion detection method requires less information and allows insects to respond quickly to threats."

Mimicking insect eyes

The researchers used a single-point diamond turning method to create 169 microlenses on the surface of the compound eye, each with a radius of about 1 mm, creating a component with a total radius of about 20 mm that can detect objects within a 90-degree field of view. Adjacent microlenses have overlapping fields of view, just like the eyes of insects.

One of the challenges in making an artificial compound eye is that the image detector is flat, while the surface of the compound eye is curved. The researchers placed a light pipe between the curved lens and the image detector, overcoming this challenge while also allowing the assembly to evenly receive light from different angles.

The researchers explained: "The bionic compound eye we created has the same ability to receive light, which is more similar to the biological compound eye. Compared with previous attempts to replicate compound eyes, it can better mimic the biological mechanism."

In order to use this artificial compound eye to measure the 3D trajectory of an object, the researchers added a grid to each hole to help with positioning, and then placed an LED light source at a known distance and direction of the compound eye, and used an algorithm to calculate the 3D position of the LED based on the position and intensity of the light emitted by the LED light source.

The researchers found that the compound eye system can quickly provide the 3D position of an object. However, when the light source is far away, the positioning accuracy decreases, which can also explain why most insects are nearsighted.

How insects see the world

"This design allowed us to demonstrate that compound eyes can identify the location of objects based on their brightness, rather than complex image processing," said the researchers. "This highly sensitive mechanism works perfectly with the brain processing capabilities of insects to help them avoid predators."

According to the researchers, this new bionic compound eye can detect the 3D position of objects, which is very useful for small robots, because small robots need to use a very lightweight system to achieve fast detection. It also provides a new way for biologists to study the visual system of insects.

The researchers also plan to embed the positioning algorithm into platforms such as integrated circuits so that the system can be integrated into other devices. In order to reduce unit costs, the researchers are also developing methods to mass-produce such compound eye lenses.