Multi-layer tactile sensor

Abstract

A sensor assembly comprising first, second and third layers of flexible material forming, when superposed, a pressure-sensitive sensor having at least two sensor cells. The first layer comprises first and second electrically conductive regions mechanically connected to each other via an electrically non-conductive region. The second layer comprises a third electrically conductive region. The third electrically conductive region of the second layer overlaps the first and second electrically conductive regions of the first layer. The region of overlap defines an active region of a first and a second sensor cell. The third layer is formed of a conductive elastic material that cooperates under a local mechanical load in the active region with the first and second conductive regions of the first layer so that an electrical resistance between the electrical conductive regions changes in the place of the compressive load. Furthermore, the sensor assembly comprises a fixation adapted to fix the first and the second layers together. The fixation is arranged outside the active region so that the first and third layers lie unloaded on top of each other in the active region and the surfaces of the first and third layers facing each other are substantially free of a fixation.