Patent attributes
A new capacitive sensor array comprises a first plurality of conductors separated by a compressible insulator from a second plurality of conductors lying in a second plane parallel to the first plane. The second plurality of conductors are paired to partially overlap the first plurality of conductors, two by one in sets, whereby a shear force applied in a plane parallel to the conductor array will cause capacitance between the first and second conductors to change. Serially sampling the two by one sets for changes in capacitance provides information on both the magnitude and direction of shear. Moreover, forces applied perpendicular to the planes causes the insulator to compress, thus also changing the capacitances of the two by one sets of the sensor array. In the preferred embodiment, the imbalance of voltages between the paired conductors is applied to a differential amplifier to sense shear magnitude and direction. Compression force appears as an increase in peak voltage magnitude in both of the paired conductors.