Monitoring Skin Temperature during Hand-Object Interactions

Modeling the thermal responses that occur when the hand makes contact with an object is essential for developing thermal feedback systems for haptic displays. When evaluating a thermal model from a physiological perspective, the temperature responses of the skin during contact are typically measured with small thermal sensors, such as thermistors or thermocouples affixed to the skin. However, it is difficult to obtain consistent temperature measurements with sensors. When the sensor is placed directly on the contact area [1, 2], it molds to the fingerpad and affects the surface area between the fingerpad and material. When it is attached to the perimeter of the contact area [3, 4], the localized nature of the change in skin temperature means that the sensor is not able to detect the full extent of the temperature change during contact. As a result, there are considerable differences in the magnitude of the changes in skin temperature recorded as a function of the location of the thermal sensor, with larger decreases reported when the sensor is directly on the contact area as shown in Figure 1.