Warm or cool, large or small? The challenge of thermal displays

Thermal displays have been developed to present thermal cues to the hand to facilitate object recognition in virtual environments or in teleoperated robotic systems. This review focuses on this application domain of thermal displays and considers the models developed to simulate the thermal interaction between an object and the hand as they make contact. An overview of thermal perception and the mechanisms underlying the processing of thermal information is provided to give a framework for analyzing the design of thermal displays. The models developed to simulate thermal feedback are examined together with a description of the implementation of these models in thermal displays. The domains in which thermal displays have been used are described; this includes the simulation of material properties, the recreation of large-scale thermal effects in virtual environments, the encoding of abstract concepts and the use of thermal feedback in interactive art. The review concludes by considering the advantages and challenges associated with using thermal displays in these diverse areas.