Tactile manual input driver-vehicle interface enabling non-driving-related tasks and emergency braking for conditionally automated vehicles

This study aimed to develop and evaluate a tactile manual input driver–vehicle interface to support simple non-driving-related tasks and emergency braking in conditionally automated vehicles. A within-participant simulator experiment with 30 drivers compared the proposed interface with a conventional interface for simple non-driving-related task usability, and with the foot brake pedal for emergency braking. User acceptance was explored by comparing participants who experienced the proposed interface with selected respondents from a previous questionnaire study. The results showed that participants completed the item-switching task significantly faster and exhibited more efficient interaction behaviours using the proposed interface. Questionnaire responses indicated higher scores on several acceptance variables than selected respondents. In the emergency braking task, reaction times were significantly shorter using the proposed interface than the foot brake pedal. These findings provide practical implications for designing tactile manual input interfaces that support simple functions and rapid driver intervention in conditionally automated vehicles.