  In modern robotic applications, tactile sensor arrays (i.e., artificial
skins) are an emergent solution to determine the locations of contacts between
a robot and an external agent. Localizing the point of contact is useful but
determining the force applied on the skin provides many additional
possibilities. This additional feature usually requires time-consuming
calibration procedures to relate the sensor readings to the applied forces.
This letter presents a novel device that enables the calibration of tactile
sensor arrays in a fast and simple way. The key idea is to design a plenum
chamber where the skin is inserted, and then the calibration of the tactile
sensors is achieved by relating the air pressure and the sensor readings. This
general concept is tested experimentally to calibrate the skin of the iCub
robot. The validation of the calibration device is achieved by placing the
masses of known weight on the artificial skin and comparing the applied force
against the one estimated by the sensors.
