While Congress has already called for alcohol-detection technology that could eventually be standard equipment in all new cars, European scientists are now proposing technology should also gauge an individual’s emotional state of mind before they take the wheel.
Such technology can already read facial expressions and identify which of the seven “universal” emotions a person is feeling: fear, anger, joy, sadness, disgust, surprise, or suspicion. This technology is being used for video game development, medicine, marketing, and, perhaps less obviously, in driver safety.
Researchers know that in addition to fatigue, the emotional state of the driver is a risk factor. Irritation, in particular, can make drivers more aggressive and less attentive.
Swiss researchers from Ecole polytechnique fédérale de Lausanne (EPFL) University in collaboration with PSA Peugeot Citroën, have developed an on-board emotion detector based on the analysis of facial expressions.
Tests carried out using a prototype indicate that the idea could have promising applications.
Although it is not easy to measure emotions within the confines of a car, especially non-invasively, researchers adapted a facial detection device using an infrared camera placed behind the steering wheel.
Nevertheless, the problem was to get the device to recognize irritation on the face of a driver.
Everyone expresses this state somewhat differently — a kick, an epithet, a nervous tic or an impassive face.
To simplify the task at this stage of the project, Hua Gao, Ph.D., and doctoral student Anil Yüce, who spearheaded the research, chose to track only two expressions: anger and disgust, whose manifestations are similar to those of anger.
Two phases of tests were carried out. First, the system “learned” to identify the two emotions using a series of photos of subjects expressing them. Then the same exercise was carried out using videos.
The images were taken both in an office setting as well as in real life situations, in a car that was made available for the project. The rapidity with which the comparison between filmed images and thus detection could be carried out depended on the analysis methods used.
Although still a prototype, the system worked well and irritation could be accurately detected in the majority of cases. When the test failed, it was usually because this state is very variable from individual to individual.
“This is where the difficulty will always lie, given the diversity of how we express anger. Additional research aims to explore updating the system in real-time — to complement the static database — a self-taught human-machine interface, or a more advanced facial monitoring algorithm,” said Hua Gao.
Detecting emotions is only one indicator for improving driver safety and comfort. In this project, it was coupled with a fatigue detector that measures the percentage of eyelid closure.
Researchers are also working on detecting other states on drivers’ faces such as distraction, and on lip reading for use in vocal recognition. These projects are coordinated by EPFL’s Transportation Center and carried out in collaboration with PSA Peugeot Citroën.