Driver Monitoring Systems

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Driver monitoring systems are a feature in modern vehicles that use sensors or cameras to determine if you are becoming fatigued or if you are paying attention to the road. 

A driver monitoring system is also referred to as a "driver attention monitor" or "driver attention warning," and these systems are part of a greater network of advanced driver assistance systems (ADAS), which are increasingly common on nearly every new vehicle in the market. ADAS include automatic emergency braking, lane keeping assistance and adaptive cruise control. With this in mind, here's why driver monitoring systems are important, how they work, and what vehicles offer them.

What are the different types of driver monitoring systems?

There are two types of driver monitoring systems. The first has been around longer and uses various sensors to monitor a driver's driving patterns. In some cases, the system can also use a forward-facing camera that monitors lane markings. If the system detects a pattern of drowsiness or inattentiveness — for example, too many steering corrections or frequent crossings of lane markers — it will alert the driver. Most systems will first use an audible alert and display a warning message (which usually looks like a steaming cup of coffee) on the instrument panel. But if the driver continues driving the same way, certain systems will vibrate the steering wheel. Mercedes-Benz says its system, called Attention Assist, continuously monitors up to 70 parameters of driving behavior. This type of driver monitoring system is less advanced and less accurate than the next. 

The other type of driver monitoring system is newer and is becoming more widely used. It uses an interior driver-facing camera. The camera can be used on its own or as part of a hands-free driving system. It continually monitors the driver's face and is usually mounted on top of the steering column. In many systems, the camera uses infrared light-emitting diodes (LEDs) that "see" the driver's face. It can also monitor the driver's face at night and can see the driver's eyes even when the driver is wearing sunglasses. 

The camera is linked to a computer that determines the driver's typical driving state when the person is awake and attentive. If the computer notices drowsiness symptoms such as frequent blinking, eyes narrowing or closing, or yawning, it will alert the driver. The camera's computer can also tell if the driver is paying attention to the road by monitoring the driver's eyes and determining if they are watching the road. If the system detects drowsiness or inattentiveness, the driver will hear audible alerts and get visual alerts on the instrument panel. Some systems, such as Ford's BlueCruise, will even briefly hit the brakes to issue an alert to the driver. If the driver still doesn't respond, as in the case of a medical emergency, certain systems can slow the car down and bring it to a stop. 

What vehicles have driver monitoring systems? 

Driver monitoring systems are widely used in today's new cars. Many automakers, such as Hyundai, Mercedes, Jeep, and Honda, offer systems that don't use driver-facing cameras. However, some Mercedes and Jeep models with hands-free driving systems use driver-facing cameras. Some models come with standard driver monitoring systems, usually in upper trims, but they are optional in others. Ask your salesman or check the vehicle's window sticker (also known as a Monroney sticker) to find out if the vehicle you want to buy has the system. The system's name varies by brand. For example Jeep calls it Drowsy Driver Detection, and Hyundai labels it Driver Attention Warning. 

Automakers that offer driver monitoring systems with driver-facing cameras include BMW, Ford (including Lincoln), GM (mainly Chevrolet, GMC and Cadillac), Tesla and Subaru. As mentioned before, systems that use driver-facing cameras usually have a hands-free driving system, but Subaru is an exception because the company doesn't offer a hands-free system. But kudos to Subaru for offering a driver-facing camera system (called DriverFocus). Most automakers who don't have hands-free driving systems make do with less advanced cameraless driver monitoring systems. 

Why are driver monitoring systems important?

According to AAA, a study conducted by the U.S. Department of Transportation's National Highway Traffic Safety Administration says that 17.6% of all fatal crashes from 2017 to 2021 involved a drowsy driver. Driver monitoring systems can help reduce the number of traffic accidents caused by drowsy drivers by alerting drivers when the system detects signs of drowsiness or inattentiveness. The driver monitoring systems that use driver-facing cameras are especially good at recognizing when drivers are distracted by their phone or something else and aren't paying attention to the road. Distracted driving is another cause of many traffic accidents. 

Although the main goal of driver monitoring systems is to prevent accidents, another reason involves vehicles with semi-autonomous driving systems (also called partial automation systems) like Volvo's Pilot Assist and Tesla's Autopilot. These systems, which work best on highways, can accelerate, brake and steer for the driver.

A study from the Insurance Institute for Highway Safety says that drivers are more likely to be distracted by multitasking while using a partially automated driving system. The study said that drivers engaged in tasks like eating, combing their hair, and using electronics while the driving system was activated. Even though the vehicle does most of the driving, the system requires the driver to pay attention at all times in case the driver needs to take control or if the system fails to detect something on the road. Strict driver monitoring systems can help prevent this type of distracted driving by monitoring the driver and issuing an alert or possibly disengaging the driving system if the driver is distracted while the driving system is activated. 

Expect the use of driver monitoring systems to increase 

Hands-free driving systems that require the driver's constant attention — also called Level 2 systems — are quickly becoming popular and require driver monitoring systems with a driver-facing camera that continuously monitors the driver when the system is activated. More advanced versions, like Mercedes' Drive Pilot, are hands-free Level 3 systems that allow drivers to take their eyes off the road while the system is activated. This type of system, which also uses a driver monitoring system with a driver-facing camera, will take longer to spread to other automakers because of federal regulations but is likely to become popular.  

The European Union passed a regulation this year that requires all new vehicles to come equipped with a slew of advanced driver assistance systems including a driver monitoring system. The United States hasn't passed a regulation like that, but the National Highway Traffic Safety Administration will require all passenger cars and light trucks to have automatic emergency braking by 2029. Other advanced driver assistance systems such as a driver monitoring system could be required in the future as well.