Individualized stress detection using an unmodified car steering wheel

Abstract

In-car passive stress sensing could enable the monitoring of stress biomarkers while driving and reach millions of commuters daily (i.e., 123 million daily commuters in the US alone). Here, we present a nonintrusive method to detect stress solely from steering angle data of a regular car. The method uses inverse filtering to convert angular movement data into a biomechanical Mass Spring Damper model of the arm and extracts its damped natural frequency as an approximation of muscle stiffness, which in turn reflects stress. We ran a within-subject study (N = 22), in which commuters drove a vehicle around a closed circuit in both stress and calm conditions. As hypothesized, cohort analysis revealed a significantly higher damped natural frequency for the stress condition (P = .023, d = 0.723). Subsequent automation of the method achieved rapid (i.e., within 8 turns) stress detection in the individual with a detection accuracy of 77%.

Emotion-Aware In-Car Feedback: A Comparative Study

“…Fakhrhosseini et al explored the use of music to mitigate angry driving [32], and Ambient Breath explored just-in-time breathing intervention with auditory, wind, and visual feedback [33]. Balters et al performed an on-road study of a haptic seat for guided breathing exercises in a car [34]. Examples of other works focusing on providing intervention for guided breathing involve haptic and voice-based stimuli [35,36].…”

The Impact of Surrounding Road Objects and Conditions on Drivers Abrupt Heart Rate Changes

“…One of the key elements of human-vehicle interaction is the prediction and analysis of drivers' states and behaviors, such as stress, anxiety, and negative emotions. Detecting and mitigating drivers' stress levels and negative emotions on the road are of high importance for decreasing accident rates as well as providing a human-centered experience in driving (Balters et al, 2021;Chung et al, 2019). Additionally, research shows that driver-state changes are associated with certain environmental events.…”

“…Integrating the above information into the human-vehicle interaction development can help mitigate the adverse effects of driving on the users and provide a human-centric driving experience. However, methods of data collection other than subjective self-reports are required to understand the real-time reaction of drivers to these environmental attributes (Balters et al, 2021). In this regard, studies have already shown the utility of drivers' psychophysiology in capturing drivers' reactions to environmental attributes.…”