The semiautonomous vehicle is the future of the automotive industry. Innovations such as forward collision avoidance radar and lane departure warning systems are evidence of a clear trend – little by little, demands on the driver are being shifted to the car. It’s easy to see how these and other safety advances could make our roadways less dangerous. After all, the vast majority of traffic accidents are the result of human error. Any technology that can take a bit of responsibility away from the guy fiddling with the radio and playing Angry Birds while traveling 70 MPH down the freeway is welcome.
But let’s not forget the ‘semi’ in semiautonomous. A recent feature in Wired Magazine explains the risks inherent in the automation of certain aspects of the driving experience. While computerized assistance can improve safety in dealing with stressful situations, it may actually have an opposite effect in less taxing ones. The deciding factor is cognitive load. Until vehicles reach the point of being fully autonomous, the driver must remain mentally engaged at all times. That isn’t a problem when navigating the gridlock of downtown at rush hour (i.e. high cognitive load), but consider the open road at its most hypnotic – a long straight featureless desert highway late at night. It can get quite boring. You might flip on the cruise control. You might activate voice navigation to let you know when to exit. Such actions reduce the cognitive load of a task that is already, perhaps, too low. The potential consequences include decreased situational awareness and increased reaction time. This can be a dangerous combination as you speed toward that stalled truck in your lane a few miles ahead.
So it seems that a safeguard is required to ensure that our safety features do indeed keep us safe. More specifically, the semiautonomous vehicle needs a means of monitoring the mental state of the driver, a way to determine whether or not he or she is sufficiently engaged in steering, braking, accelerating, etc. There are several ways to measure task-based cognitive workload. They run the gamut from paper-and-pencil subjective ratings (e.g. the NASA-TLX) to complex objective readings of brain activity (e.g. EEG). Obviously, you aren’t going to ask people to fill out a questionnaire or wear a network of electrodes every time they take a trip to the supermarket. The goal is to make driving safer without adding further complications. If we want to monitor workload in a real world driving scenario, we’re going to need something a bit more subtle.
EyeTracking, Inc. has a solution. The Index of Cognitive Activity (ICA) is an objective, unobtrusive means of measuring cognitive workload. Instead of relying on driver feedback or direct physiological sensors, the ICA algorithm analyzes fluctuations in pupil size while minimizing light effects. Best of all, this patented metric relies on a tool that will most likely be available in tomorrow’s cars anyway – eye tracking. The benefits of monitoring not only point of gaze, but also workload are undeniable. In this model of ICA-enhanced eye tracking, your car will be able to address four critical driving questions: (1) are your eyes are opened? (2) are your eyes focused on the road? (3) are you cognitively overwhelmed and (4) are you cognitively underwhelmed? This information can be used in real-time to alert you to the greatest hazard out there – your own visual and mental behavior.
Several major automakers have discovered this valuable metric and put it to use in their testing labs. For example, the BMW group conducts groundbreaking research using the ICA to evaluate cognitive workload during critical driving events (Schwalm, 2008). For another automaker, the ICA has been employed to examine the differences between professional racers and normal drivers. These and other applications represent key steps toward integration of a cognitive workload gauge into the next generation of automobiles. Additional R&D is required, but hopefully a new breed of semi-autonomous vehicles, capable of evaluating the mental state of the driver, is just a bit further down the road.
Featured image from Unsplash.
