The project directly ties into the institute’s growing endeavor into connected-vehicle technology.

There are a number of reasons to bring adaptive traffic signage and warnings directly into cars:

• Stopping at an intersection before proceeding through when no other vehicles are present wastes fuel and time.

• Roadside stop and yield signs are often overlooked or outright ignored; 3,069 people were killed at stop-sign controlled intersections in the US in 2012.

• Physical signs are costly; they must be kept up, replaced when damaged, and there’s always the danger of a sign being stolen or covered by tree growth

• Other traffic signs only have limited use—e.g., the “Bridge Freezes Before Road” sign during the summer.

This is part of our initial efforts to integrate more revolutionary safety concepts with the growing field of connected-vehicle technology. While a relatively new area in the transportation realm, adaptive stop/yield signs have the potential to be a long-term solution for not only minimizing traffic problems experienced on increasingly congested roadways, they may also help mitigate negative environmental impacts.

—Thomas Dingus

Noble recently finished a 17-week closed experiment at the Virginia Smart Road, directly behind the institute’s main base, involving dozens of local test participants, aged 18-25 and then older than 50, in cars outfitted with small GPS-like dashboard screens that would alert the driver with a flashing display to either stop or yield, and proceed through the intersection. Additional cars at intersections during the tests were driven by institute researchers trained to safely interact with the participant driving test vehicles.

Test subjects were filmed by cameras set up inside the institute-provided test vehicle, capturing images of the motorist’s upper body, line of sight, the dashboard, and the vehicle itself. Also part of the test were scenarios in which the automated sign technology was allowed to fail, leaving the test subject to act on their his or her own accord.

This study was set up to take place in a future where all static traffic control infrastructure, such as stop signs and yield signs, are no longer needed, and you have an adaptable in-vehicle display telling you when you need to stop and when a stop is unnecessary.

The deployment of this technology in the real world would involve a whole re-working of the transportation system and is not likely to be deployed in the near future. However, this study will be useful in developing future connected-vehicle applications in a general sense and demonstrates that this is possible and how well it is received by naive drivers with minimal training on the subject.

—Alexandria Noble

The project is only beginning, and there has been no testing in real traffic environments. Hours of footage of tests subjects will be reviewed and compared to that of drivers filmed during naturalistic conditions in separate institute studies. Fail-safe measures will need to be developed. Intersections involving physical signs have not yet been tested, nor have traffic lights.