Evaluation of a user-accessible countermeasure: Effect of manual dexterity gymnastics on passive driver fatigue

Driver fatigue remains a critical concern in the realm of traffic safety. In particular, passive driver fatigue, promoted by prolonged exposure to low-workload driving and boredom, not only poses threats to daily driving but also may compromise the effectiveness of takeover in future autonomous driving. Commonly adopted strategies involve activities that drivers can engage in to awaken their bodies and minds, or in-vehicle interactive systems implemented by manufacturers to alleviate boredom. However, there is currently limited focus given to user-accessible in-vehicle physical activities aimed at addressing passive fatigue. Therefore, this study proposed manual dexterity gymnastics as finger exercises that are conveniently implemented against passive driver fatigue. The finger exercises consisted of tapping the fingertip, pressing nail roots, flicking fingers, pressing the sides of fingertips, and closing and opening the fingers. To evaluate this countermeasure, eighteen participants performed a monotonous driving task using a driving simulator. The driving sessions each lasted 90 min. Each participant drove in two sessions consisting of either manual dexterity gymnastics or watching videos. Passive driver fatigue was assessed by physiological indexes, driving performance analysis, vigilance assessment, and subjective evaluation. The manual dexterity gymnastics significantly suppressed driver fatigue according to the percentage of eyelid closure, blink frequency, and steering reversal rate. Furthermore, vigilance was also improved, and the subjective evaluation showed that fatigue was significantly lower. The experimental results suggested that manual dexterity gymnastics may be regarded as an effective countermeasure to suppress the deterioration of passive driver fatigue.