Effects of vibrotactile signals coupled with pressure detection or timer when interacting with a touch screen in automobile

The aim of our study was to determine the benefit of vibrotactile feedback when interacting with the Lane Change Task (LCT) simulated driving display, but also to compare three modes of driving interaction: the pressure, the timer and the capacitive during two types of tasks: the slider and the push. The thirty-three participants were initially separated into two groups, depending on the type of task (slider or push) and thus conducted under two levels of cognitive load modulated by the OSPAN task (operation-word-span) which solicits working memory where the participant is asked to check the accuracy of a calculation or retain a word while interacting with a touch screen and performed these tasks in a driving simulator. The subjective results showed that i) for the slider, the pressure is preferred over the capacitive and timer modes. However, this is not verified for the pushes, ii) The subjective questionnaires confirmed the interest of the vibrotactile return as well in terms of preference, feeling of security and confidence regarding the touch screen. Conversely, the results obtained via the Driving Activity Load Index (DALI) questionnaire did not show any significant results.