We present a novel approach to render thermal and tactile feedback to the palm and fingertips through thermal and tactile integration. Our approach minimizes the obstruction of the palm and inner side of the fingers and enables virtual object manipulation while providing localized and global thermal feedback. By leveraging thermal actuators positioned strategically on the outer palm and back of the fingers in interplay with tactile actuators, our approach exploits thermal referral and tactile masking phenomena. Through a series of user studies, we validate the perception of localized thermal sensations across the palm and fingers, showcasing the ability to generate diverse thermal patterns. Furthermore, we demonstrate the efficacy of our approach in VR applications, replicating diverse thermal interactions with virtual objects. This work represents significant progress in thermal interactions within VR, offering enhanced sensory immersion at an optimal energy cost.
https://doi.org/10.1145/3654777.3676457
Skin temperature is an important physiological factor for human hand dexterity. Leveraging this feature, we engineered an exoskeleton, called DexteriSync, that can dynamically adjust the user's finger dexterity and induce different thermal perceptions by modulating finger skin temperature. This exoskeleton comprises flexible silicone-copper tube segments, 3D-printed finger sockets, a 3D-printed palm base, a pump system, and a water temperature control with a storage unit. By realising an embodied experience of compromised dexterity, DexteriSync can help product designers understand the lived experience of compromised hand dexterity, such as that of the elderly and/or neurodivergent users, when designing daily necessities for them. We validated DexteriSync via a technical evaluation and two user studies, demonstrating that it can change skin temperature, dexterity, and thermal perception. An exploratory session with design students and an autistic compromised dexterity individual, demonstrated the exoskeleton provided a more realistic experience compared to video education, and allowed them to gain higher confidence in their designs. The results advocated for the efficacy of experiencing embodied compromised finger dexterity, which can promote an understanding of the related physical challenges and lead to a more persuasive design for assistive tools.
https://doi.org/10.1145/3654777.3676422
This study introduces "Flip-Pelt," a motor-driven peltier device designed to provide rapid thermal stimulation and congruent pressure feedback in virtual reality (VR) environments. Our system incorporates eight motor-driven peltier elements, allowing for the flipping of preheated or cooled elements to the opposite side. In evaluating the Flip-Pelt device, we assess user ability to distinguish between heat/cold sources by their patterns and stiffness, and its impact on enhancing haptic experiences in VR content that involves contact with various thermal sources. Our findings demonstrate that rapid thermal stimulation and congruent pressure feedback provided by Flip-Pelt enhance the recognition accuracy of thermal patterns and the stiffness of virtual objects. These features also improve haptic experiences in VR scenarios through their temporal congruency between tactile and thermal stimuli. Additionally, we discuss the scalability of the Flip-Pelt system to other body parts by proposing design prototypes.
https://doi.org/10.1145/3654777.3676363
We control the temperature of materials in everyday interactions, recognizing temperature's important influence on our bodies, minds, and experiences. However, thermal feedback is an under-explored modality in human-computer interaction partly due to its limited temporal (slow) and spatial (small-area and non-moving) capabilities. We introduce hydroptical thermal feedback, a spatial thermal feedback method that works by applying visible lights on body parts in water. Through physical measurements and psychophysical experiments, our results show: (1) Humans perceive thermal sensations when visible lights are cast on the skin under water, and perceived warmth is greater for lights with shorter wavelengths, (2) temporal capabilities, (3) apparent motion (spatial) of warmth and coolness sensations, and (4) hydroptical thermal feedback can support the perceptual illusion that the water itself is warmer. We propose applications, including virtual reality (VR), shared water experiences, and therapies. Overall, this paper contributes hydroptical thermal feedback as a novel method, empirical results demonstrating its unique capabilities, proposed applications, and design recommendations for using hydroptical thermal feedback. Our method introduces controlled, spatial thermal perceptions to water experiences.
https://doi.org/10.1145/3654777.3676453