In this paper, a numerical model of the thermal process of touching an object is described. The model takes into account the object geometry and temperature, the thermal parameters of the material and the contact resistance between finger and object. Based on the heat extraction rate, this model predicts which materials will feel warm or cold to the touch. The model is empirically verified with psychophysical experiments. In a temperature-controlled box, subjects had to discriminate between stimuli of different materials and geometries based on thermal cues. The results are in line with the idea that the perceived `coldness' of materials is determined by the initial heat transfer rate, as predicted by the model.
Wouter M. Bergmann Tiest