What feels light to you? An exploration into supplying simple information through a light bar in a highly automated vehicle

As advanced features integrate into vehicle, drivers may feel apprehensive to use them. Providing users information using human-machine interfaces (HMIs) may ease fears; however, in highly automated vehicles, the optimal method of displaying information is unclear. Our study examined how using a light strip to transmit varying degrees of information (none, redundant, or supplemental) impacted trust and acceptance in participants (N = 36) across two drives using self-report and physiological measures. We also analyzed which measures predicted psychological comfort in an exploratory investigation of the largely undefined concept. The results indicated no significant effects suggesting that transmitting information through a light strip and its presence may not impact users. In a regression, only trust significantly explained variance of psychological comfort. Future research would benefit from examining what factors influence psychological comfort. Given our young participant demographic, it is possible future AI users may remain unaffected by additional non-textual HMI displays.