Realistic thermal haptics for discriminating materials with identical temperatures

Abstract

Realistic thermal feedback is essential for improving immersion in virtual and augmented reality (VR/AR) systems. However, conventional wearable thermal devices often fall short in replicating the subtle thermal sensations associated with real-object contact, largely owing to their oversimplified emphasis on temperature while overlooking the complex interplay between object thermal properties and human thermophysiology. In this study, we propose a bioheat-based thermal contact model that enables accurate thermal haptic reproduction, allowing users to distinguish between objects with identical surface temperatures. To validate the model, we conducted finite element simulations and controlled experiments using materials (wood and copper) maintained at the same temperature. The results indicate that both interfacial temperature and heat flux exhibit time-dependent behavior and must be concurrently regulated to reproduce realistic thermal haptic feedback. Overall, this study establishes a comprehensive framework for developing wearable thermo-haptic systems capable of delivering lifelike thermal sensations in VR/AR and broader human–machine interface applications.