Research shows ‘active’ signs could aid pedestrian safety


Researchers from the University of Michigan (U-M) and Brigham Young University (BYU) have discovered a way to provide a few extra milliseconds in driver reaction times, which could be crucial for pedestrians’ safety. The new study finds that drivers react significantly faster to warning signs that depict greater movement. Co-author, Ryan Elder, a professor in BYU’s Marriott School of Management, and lead authors, Luca Cian and Aradhna Krishna of the University of Michigan, pursued research to explore how static imagery that implies motion can impact behavior. Using driving simulations, click-data heat maps, surveys, reaction time exercises and eye-tracking, the trio found that signs conveying a higher perception of movement, lead to quicker reaction from observers.

Signs depicting figures or other images that appear to be moving at higher speeds, create a faster reaction time than those where the image shows less ‘dynamism’. In one study experiment, researchers found that participants in a driving simulation reacted an average of 50 milliseconds faster to warning signs with higher dynamism. For a car traveling at 60mph (96km/h), 50 milliseconds equates to an extra 4.4ft (1.3m) of road, which could make a crucial difference in vehicle/pedestrian collisions. In a second experiment, the team used eye-tracking technology to measure how long it takes a person’s eyes to notice a traffic sign. The eye-tracker results showed that signs with higher perceived movement attracted and maintained significantly earlier attention than static signs.

“A sign that evokes more perceived movement increases the observer’s perception of risk, which in turn brings about earlier attention and earlier stopping,” explained Elder. “If you want to grab attention, you need signs that are more dynamic. If the figures look like they’re walking, then your brain doesn’t worry about them shooting out into the road. But if they’re running, then you can imagine them being in front of your car in a hurry. “Things that look like they’re going to move, get moved in our minds. Our minds want to continue the motion that is contained within an image; and that has important consequences.” The researchers believe increasing the number of ‘dynamic’ warning signs will help increase the effectiveness of those signs and ultimately lead to fewer deaths on the road.

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Tom has edited Traffic Technology International (TTi) magazine and its Traffic Technology Today website since May 2014. During his time at the title, he has interviewed some of the top transportation chiefs at public agencies around the world as well as CEOs of leading multinationals and ground-breaking start-ups. Tom's earlier career saw him working on some the UK's leading consumer magazine titles. He has a law degree from the London School of Economics (LSE).