Thermal feedback has been proven to enhance user experience in human-machine interactions. Yet state-of-the-art thermal technology has focused on the single finger or palm in static contact, overlooking dynamic and multi-finger interactions. The underlying challenges include incompatible designs of conventional interfaces for providing salient thermal stimuli for such interactions and, thereby, a lack of knowledge on human thermal perception for relevant conditions. Here we present the ThermoSurf, a new thermal display technology that can deliver temperature patterns on a large interface suitable for dynamic and multi-finger interactions. We also investigate how user exploration affects the perception of the generated temperature distributions. Twenty-three human participants interacted with the device following three exploration conditions: static-single finger, dynamic-single finger, and static-multi finger. In these experiments, the individuals evaluated 15 temperature differences ranging from -7.5°C to +1.5°C with an initial temperature of 38°C. Our results showed that human sensitivity against thermal stimuli is significantly greater for static-single finger contact compared to the other tested conditions. In addition, this interaction type resulted in higher thermal discrimination thresholds than the ones reported in the literature. Our findings offer new perspectives on providing salient and consistent thermal feedback for future tactile interfaces.

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This study is the third iteration in a series of studies aimed to develop a system that allows driving blindfolded. We used a sonification approach, where the predicted angular error of the car 2 seconds into the future was translated into spatialized beeping sounds. In a driving simulator experiment, we tested with 20 participants whether a surround-sound feedback system that uses four speakers yields better lane-keeping performance than binary directional feedback produced by two speakers. We also examined whether adding a corner support system to the binary system improves lane-keeping performance. Compared to the two previous iterations, this study presents a more realistic experimental setting, as participants were unfamiliar with the feedback system and received the feedback without headphones. The results show that participants had poor lane-keeping performance. Furthermore, the driving task was perceived as demanding, especially in the case of the additional corner support. Our findings from the blind driving projects suggest that drivers benefit from simple auditory feedback; additional auditory stimuli (e.g., corner support) add workload without improving performance@en