A new technique for touch sensing based on measurement of current generated by electrostatic induction

In this paper, we propose a new concept for touch sensors that is based on measurement of the current generated by electrostatic induction. The proposed sensor can detect the timing of contact between two objects from a distance without contact with either object. When the human body comes in contact with an object, electrostatic charge is generated in the human body due to tribological interactions. We assume that the human body is a good conductor. As a result, an instantaneous change is observed in the electric potential of the human body. Therefore, contact can be detected via the change in the electric potential of the human body. We have developed an effective technique for measuring the change in the electric potential of the human body using a noncontact electrode. Such indirect measurement is made possible by the measurement of the instantaneous current flowing through the electrode, instead of measurement of the voltage of the electrode by the conventional capacitively coupled method. This new technique requires measurement of the electrostatic induction current generated due to changes in the electric potential of the human body.