Professional Engineering

Researchers at the Fraunhofer Institute for Digital Media Technology in Ilmenau, Germany, have developed a system that tracks a driver’s eye movements and issues a warning before the driver has an opportunity to nod off to sleep.

The special feature of the Eyetracker is that it can be installed in any model of car and there is no need for a complicated calibration of the cameras, the researchers said. “With conventional systems, every person whose line of vision is to be monitored has to complete more or less time-consuming preparations. Because every head, every face, every pair of eyes is different,” said Professor Husar of the IDMT.

The Eyetracker system does not require a PC or a laptop. “What we have developed is a small modular system with its own hardware and programs on board, so that the line of vision is computed directly within the camera itself. Since the Eyetracker is fitted with at least two cameras that record images stereoscopically – meaning in three dimensions – the system can easily identify the spatial position of the pupil and the line of vision,” said Husar. The information is fed out through a standard interface such as USB or CAN. This means the Eyetracker can be connected directly to the car’s trip computer.

If the camera modules detect the driver’s eye is closed for longer than a user-defined interval, it sounds an alarm. When used as a driver-assistance system, there can be four to six cameras keeping watch over the driver’s eyes. The cameras evaluate up to 200 images per second to identify the line of vision, even when a driver’s head moves to the left or right. 

The Eyetracker is roughly half the size of a matchbox and can be mounted the sun visor and in the dashboard. Its lenses are three to four millimeters in diameter.

In medicine, the camera system could also be used to assist eye operations by registering a patient’s eye movements.