Distracted driving caused by smartphone use remains a serious safety concern, and one solution is disabling certain phone features such as texting while the user is driving. However, detecting whether it’s the driver or a passenger using the phone has been problematic. Now, U of M researchers are addressing this challenge with a new method for automatically identifying the position of a smartphone inside a moving vehicle.
“Determining whether a phone is inside a moving vehicle is simple using GPS speed data, but determining the phone location inside the vehicle is much more challenging,” says Rajesh Rajamani, a professor in the Department of Mechanical Engineering.
Previous systems have required external hardware, wireless communication with the vehicle, or access to the phone’s camera, Rajamani explains. The goal of this research was to develop a method that uses only the non-camera sensors already available on the phone.
Researchers began by developing a method to determine, in real time, how the phone is positioned in relation to the vehicle, since the phone could be carried in a purse or pocket, on a display stand, or in the user’s hands. Next, researchers conducted simulations and experiments to determine how a vehicle pitches and rolls from front-to-back and side-to-side as it moves and turns, and how those movements correlate to the phone’s position within a vehicle. Finally, those roll-and-pitch dynamics were used to create a new algorithm, which was then tested through simulations and experiments.
“Our research shows that the system we developed can accurately determine if the phone is being carried by the driver or passenger of a vehicle, provided the terrain is flat and the phone’s orientation does not keep changing rapidly,” Rajamani says. “This technology could be a very valuable tool for correctly disabling texting features for the driver only.”
The research was supported in part by a research grant from the National Science Foundation and was published in the journal Vehicle System Dynamics. Graduate student Gregory Johnson is the lead author of the article.
