University of Illinois at Urbana-Champaign (UIUC) researchers have developed a bio-inspired camera for autonomous vehicles.
The camera, which is based on the visual system of the mantis shrimp, could improve a car’s ability to spot hazards in challenging imaging conditions.
According to a report published in Optical Society’s Optica, the new device is capable of detecting polarization and features a dynamic range 10,000 times higher than that of today’s cameras.
This range allows the camera to see better in driving conditions especially when it transits from a dark tunnel into bright sunlight or during hazy or foggy conditions.
“In a recent crash involving a self-driving car, the car failed to detect a semi-truck because its color and light intensity blended with that of the sky in the background,” said team lead Viktor Gruev. “Our camera can solve this problem because its high dynamic range makes it easier to detect objects that are similar to the background and the polarization of a truck is different than that of the sky.”
In order to achieve a high dynamic range for their camera, the researchers tweaked the way the camera’s photodiodes convert light into an electrical current.
And instead of operating the photodiodes in reverse bias mode – which is traditionally used for imaging – the researchers used forward bias mode.
This changed the electrical current output from being linearly proportional to the light input to having a logarithmic response like the shrimp.
For the polarization sensitivity, the researchers mimicked the way that the mantis shrimp integrates polarized light detection into its photoreceptors by depositing nanomaterials directly onto the surface of the imaging chip that contained the forward biased photodiodes.
“These nanomaterials essentially act as polarization filters at the pixel level to detect polarization in the same way that the mantis shrimp sees polarization,” said Gruev.
The researchers are currently working with an air bag manufacturer to see if the camera’s high dynamic range and polarization imaging capability can be used to avert a collision, or deploy the air bag a few milliseconds earlier than is currently possible.
Viktor Gruev, University of Illinois at Urbana-Champaign
