Harman’s pupil-based driver monitoring system

Harman’s pupil-based driver monitoring system

Research by the Royal Society for the Prevention of Accidents shows that driver fatigue may be a contributory factor in up to 20 percent of road accidents. While driver alert systems – aimed at identifying signs of driver fatigue – have been around for a while, eye tracking and camera-based facial recognition technology are under development. This research snapshot reviews the stage reached with driver alertness technologies and what we can expect to see on tomorrow's cars.

Driver alert systems

Volvo was among the early adopters of driver alert technologies. The Swedish automaker introduced Driver Alert Control way back in 2007.  We have since seen such systems offered by a number of OEMs using different guises, including Ford (calling it Driver Alert), BMW (Active Driving Assistant), Mercedes-Benz (Attention Assist), Toyota (Driver Monitoring System), and VW (Fatigue Detection System).

Driver fatigue systems typically work by monitoring driver behaviour, noting any erratic steering wheel movements, lane departures or changing speeds for no reason. As these elements tend to suggest a drowsy driver, most solutions involve trying to grab the driver's attention via a flashing/blinking dashboard display and/or audible warning.  For example, Volkswagen's system uses a flashing display and series of beeps if it detects that a driver is starting to lose concentration. If the driver has not taken a break within 15 minutes, the system will repeat the warning. Ford's Driver Alert works along similar lines.  If a dozy driver ignores a warning, the system can only be reset by pulling over and opening the driver's door. The system then recognises that the driver has either taken a break or changed drivers.

Eye tracking technologies

When cars are finally on the road in a highly automated mode, driver monitoring will become even more significant. Hence the focus of development is on camera-based facial recognition technology.

Given that there are lots of things that can divert a driver's attention, Magna's solution comes in the form of a camera-based monitoring system. It detects the driver's eye gaze and measures levels of drowsiness and distraction. The head-up display projects an unobstructed image from the rear camera, using eye gaze determination to identify when a driver looks up at the interior mirror to get a rearward view. 

Developed along similar lines, Harman's eye tracking system can also monitor a driver's alertness levels. It uses eye tracking software and a camera to monitor a driver's state of alertness.

For its part, Delphi used the most recent Consumer Electronics Show to demonstrate several of its latest advanced technologies including a touch-free cockpit and 3D instrument cluster. Delphi's touch-free cockpit uses hidden infrared cameras to track eye movement to detect what a driver is looking at and infers what action should be carried out by the infotainment system. The supplier's 3D cluster uses multi-layer graphics technology to create a high-end, enhanced driving experience.

GM has let it be known that its Super Cruise, a highway driving automation technology that will enable hands-free driving even in stop-and-go traffic, will be introduced in China shortly after it becomes available next year in the Cadillac CT6 in the US. Super Cruise incorporates driver eye tracking technology to ensure they are paying attention when using the optional semi-autonomous system. The system triggers an initial warning if it detects that the driver's attention is drifting off while Super Cruise is activated. But if this is ignored then an OnStar operator will attempt to make contact with the driver via the intercom. If still no response then the car will be pulled safely over to the side of the road. 

Meanwhile, Omron has developed a prototype facial recognition system for cars that use an infrared camera to track the driver's eye movements and gestures. Similar to the approach used in Super Cruise, when Omron's system detects the driver is not responding to any warning or signal, it slows the car down and brings it to a halt.

Other driver alertness solutions

Faurecia has taken an entirely different approach. Among the supplier's technologies showcased at the last year's Frankfurt motor show included its so-called Active Wellness, a car seat that can detect occupant stress levels. It was developed with support from Stanford University with the aim of keeping drivers alert and comfortable while in a self-driving car. The seat is embedded with piezoelectric sensors to measure the driver's heart rate and breathing rhythms. If it detects the driver's stress levels, counter-measures such as a seat massage will be offered on a touchscreen.

Explaining the reasons behind this development, Geoffroy de Grandmaison, marketing director, Faurecia told just-auto: "You cannot have an autonomous car without a good and comprehensive assessment of the driver status. Are you distracted at all? Are you turning behind to talk to your children? Are you a bit drowsy? Are you under pressure? The autonomous car needs to know that. The seat is one of the best car components to have reliable information such as blood pressure, temperature, humidity, respiration, weight, pressure map and so on. It is difficult to cheat on a seat."

Another novel departure from eye tracking comes from Audi in the form of its Fit Driver. Audi states its Fit Driver "focuses on the well-being and health of the driver." It works by the driver wearing fitness wristband or smartwatch that monitors important vital parameters such as heart rate and skin temperature. Vehicle sensors supplement this data with information on driving style, breathing rate and relevant environmental data such as weather or traffic conditions. The current state of the driver, such as elevated stress or fatigue, is deduced from the collected data. As a result, various vehicle systems act to relax, vitalise, or even protect the driver.

Finally, Plessey used the most recent Paris motor show to demonstrate a heart-rate based driver alertness monitoring system. The company worked with Segula Technologies to develop the seatback system, known as EPIC. It can sense the electrical impulses of the heart without direct skin contact and can return an accurate R peak signal from the user's electrocardiograms which can be used to calculate heart rate variability. The partners say the EPIC sensor electrodes can be incorporated inside car seatbacks to access the necessary biometric signals and provide earlier warning of drowsiness or health issues than systems based on eye or head movement.

See also: Global light vehicle safety systems market - forecasts to 2031