Ohio State EcoCAR research aims to improve safety of autonomous vehicles

Autonomous vehicles can accelerate, brake and steer all on their own; however, there are some situations that require the driver to take control. The Ohio State University EcoCAR team studied various warning methods to determine which was the most effective in alerting the driver.

The study’s participants were placed in the Ohio State Driving Simulation Laboratory, which was built in partnership with Honda R&D Americas. The state-of-the-art driver-in-the-loop simulation system makes participants feel like they are driving a real vehicle, allowing researchers to test drive scenarios that are not safe on public roads.

Inside the lab, a Honda Accord is surrounded by curved screens and raised on a moving platform. The screens display the road and traffic, and the platform leans the car forward, backward and side to side depending on whether the driver accelerates, brakes or steers. The simulator even plays the sounds associated with driving a car.

The EcoCAR team studied five warning systems: a flashing head-up display, flashing LEDs across the interior, a haptic vibration system, rapid beeps and a voice warning the driver that the system is unavailable. To test these systems, participants played a game on a tablet while the vehicle drove itself in the simulator, and the vehicle would randomly warn the driver to take control. Researchers then measured their reaction times to each warning system.

The study found that the reaction times had little variation after the participant was exposed to the first warning. The driver learned when and how to react to each subsequent warning, almost like reacting to a fire drill.

Simon Trask, Ohio State EcoCAR’s engineering manager, presented the findings at the Society of Automotive Engineers (SAE) World Congress Experience in Detroit, Michigan on April 11. He said that although the results were not particularly surprising or groundbreaking, he noticed other surprising findings, such as how the driver interacted with the tablet.

“What was interesting was how people behaved during their reaction period,” Trask said. “Many participants were out of position because they were setting the tablet on the passenger seat, so the passive safety systems like the seat belt and airbag would not work properly. Other people would hold the tablet directly in front of the steering wheel, which could turn the airbag into a dangerous cannon."

Trask also said that innovators are looking to other industries for solutions to keep the driver engaged. Some researchers are applying concepts from the video game industry to “gamify” a vehicle’s interior. For example, while the vehicle is driving itself, the driver would have to look at points on the windshield to win the game. This keeps the driver focused on the road and ready to react if the vehicle needs them to take control.

“The idea of bringing the game industry into automotive makes us wonder, ‘Where are we going to find a solution next?’” Trask said. “What industries will inspire researchers and engineers to solve problems in autonomous vehicles?'

Ohio State EcoCAR’s next research project addresses driver distraction directly. The team is developing a camera system that tracks the driver’s eyes and knows when they are distracted. 

The EcoCAR team plans to use the findings from both studies when it implements semi-autonomous systems in its 2019 Chevrolet Blazer during the EcoCAR Mobility Challenge. Read the full research article here.

by Jake Berg, Center for Automotive Research communications intern