When eye tracking in cars, what works and what doesn't?
How should the eye tracker be configured to work with the outdoor lighting in a car?
What advantages does EyeTech have with eye tracking in cars?
Does it work through sun glasses? What other factors should be considered?
asked 23 Feb '15, 18:20
Eye tracking and face tracking has a long history of use in commercial vehicles, especially mining vehicles. Multi-million dollar mining vehicles could have the eye tracker added without worrying about the cost or space or computing requirements. Eye tracking in other markets is becoming more of a reality as eye tracking technology has been advancing and changing.
A dark pupil based eye tracker can track the user's eyes across 70+ eye degrees of rotation, or roughly 40 eye degrees off center from where the camera is placed. After the rotation of the eye off the axis of the camera exceeds 40 degrees off center, the cornea reflections fall off the cornea and are not as reliable to track off of.
To track across a larger angle around the user, multiple eye trackers can be added fairly easily. EyeTech's AEye chip is unique in that it has a light load on the USB bus, and can share the bus with several eye trackers without an issue. So with 3 eye trackers placed 70 degrees offset from one another, you can get 210 degrees out of 360 around a user.
Sun Light and Sun Glasses
Eye tracking works in the near IR spectrum, which also is found in sunlight.
Sun glasses tend to allow IR light without a problem. Any glasses that are heavily scratched or bifocals or trifocals tend to cause unnecessary artifacts on the eyes, preventing the view of the pupil to the eye tracker.
Image Processing and Computers in Cars
Image processing in cars has been on the rise with self driving cars since about 2013.
EyeTech's key advantage here is the AEye eye tracking on a chip. An Android tablet or a light weight Windows computer can be used to initialize the eye tracker and give the feedback to the user, or do the data logging, and the heavy lifting of the image processing and measuring the eyes are all done on the AEye chip.
Or it can be added to an existing computer setup in the car pretty easily.
CAN bus support could be added, too. The eye tracker can track and measure pupils standalone without a computer.
Placement in the Cab
Some difficulties include the placement of the eye tracker and the IR lights without either getting blocked by the user's hands or steering wheel. For the best measurements, the eye tracker should be placed just below the area that is to be tracked.
Heads Up Display (HUD)
In the assistive technology world, eye tracking has been used for controlling and interacting menus and buttons has been around for a long time. The driver doing such an interaction should probably only be done with a HUD, or a heads up display, so the user never lets his/her eyes leave the road. Drivers would also not have to worry about moving their hands off the steering wheel either!
Tablets and other devices in the car for entertainment and information for the passengers are on the rise, too.
Eye tracking can give a hand free interaction for using the interface. EyeTech's QuickKIOSK demo shows how to select menus, control video playback and navigate an interface with a painless calibration and the high speed eye movements.