Driver Monitoring Systems awaken the driver's attention and can thus prevent fatal accidents.
Driver Monitoring Systems awaken the driver's attention and can thus prevent fatal accidents.
( Source: ©metamorworks -

SAFETY What are Driver Monitoring Systems and why do we need them?

Author / Editor: Seth Lambert / Nicole Kareta

While driver monitoring may have been looked at some years ago as a “nice-to-have” or “extra” feature for autonomous vehicles, it’s quickly becoming an integral part of advanced platforms for these automobiles. But what exactly is the technology good for?

When an auto enthusiast hears the phrase “driver monitoring,” they may think of several different functions. The most common of these that driver monitoring accomplishes is that it makes sure drivers stay awake, via the use of audio alerts, or, in extreme cases, vibrations in a vehicle’s steering wheel, seat belts, and/or driver’s seat. Auto accident fatalities in the United States that can be attributed to drivers falling asleep at the wheel number roughly 1,550 annually. It’s estimated that Driver Monitoring Systems could prevent at least 50 % of these deaths if they were used as envisioned by car manufacturers.

Early Driver Monitoring Systems relied only on sensors to check a car’s steering wheel column for minute movements to tell if a driver was asleep or awake and actively navigating the vehicle. Tesla is one carmaker OEM that still utilizes this variant of a Driver Monitoring System, which could be a contributing factor in multiple fatal accidents that have occurred when Tesla drivers began to over-rely on their vehicles’ Autopilot autonomous driving features. Today’s more advanced Driver Monitoring Systems utilize cameras and infrared technology to detect which direction a driver’s face is aimed at and where their eyes are looking—even in the dark or if the driver is wearing sunglasses.

Besides sleep, other big culprits of traffic fatalities are drunken/impaired and/or distracted driving. By scanning the retinas and facial expressions of a driver multiple times per second, an advanced Driver Monitoring System can tell if the driver has his or her attention on the road and/or if he or she could be under the influence of alcohol or narcotics. In the case of such impairment, the goal of the Driver Monitoring System is to enable the vehicle to decelerate and stop safely as quickly as possible to prevent any potential accidents from occurring.

With distracted driving, the goal is to bring a driver’s attention back to the road and his or her surroundings. In 2017, distracted driving was responsible for at least 3,166 fatalities in the United States. A continuously operating factory-installed Driver Monitoring System should be able to detect some or all of the above cases and respond according to the automaker’s requirements.

Driver monitoring and autonomous vehicles

While all of the above capabilities sound like “nice to have” features on a car, when one makes the transition to partial or fully autonomous driving, driver monitoring starts to become essential equipment to have aboard a vehicle. The Society of Automotive Engineers (SAE) defines Level 3 automotive autonomy as “conditional automation” whereby drivers are permitted to take their hands off the steering wheel of their cars, but still must keep their attention on the road in case the vehicle needs to return driving functionality to the driver (which is typically accomplished in a matter of a few seconds). Driver monitoring can come into play to see if the driver is drowsy, distracted, under the influence of alcohol or drugs, or otherwise impaired. In cases where a driver is unwilling or unable to retake manual control of their vehicle, most autonomous vehicle (AV) platforms decelerate and stop the vehicle safely as described above.

What’s interesting about SAE Autonomy Level 3 is that in some places, such as Japan—where traffic safety laws do not normally allow drivers to take their hands off the steering wheel in order to let an AV platform take over driving—the Driver Monitoring System is a mitigating factor that the government has accepted for safety requirement fulfillment in lieu of the driver’s hands on the steering wheel. Essentially, the Driver Monitoring System keeps the driver’s attention on the task of driving, so that even if their hands are not physically on the steering wheel, their attention is continually re-directed to the task of vehicle navigation, and this satisfies the government’s legal requirements.

More and more, developers of AVs and AV technology are starting to see driver monitoring as an essential component of AV platforms as they begin to transition from SAE Level 2 to SAE Levels 3 and 4. Autonomous driving opens up a huge realm of liability for automakers, and driver monitoring is a nearly foolproof way to make sure the human link in the autonomous driving chain is performing its duties when and where required.

Even without AV features, beginning in 2020, the European New Car Assessment Program (EuroNCAP) will be starting to evaluate the effectiveness of new car Driver Monitoring Systems, and it’s expected that to achieve a top EuroNCAP score, an automaker will have to include a high-quality system in its vehicles. Additionally, the European Union has mandated Driver Monitoring Systems for inclusion in all new automobiles by the middle of 2022.