Abstract
In this work, we propose a novel capacitance tactile sensor with flexibility and transparency using polydimethylsiloxane (PDMS), polyethylene terephthalate (PET), and indium tin oxide (ITO) for based materials. This sensor can measure normal force and shear force simultaneously. Each capacitance sensor cell consists a top electrode layer, a spacer layer, an insulation layer, and a bottom electrode layer. We use differential capacitance changed to measure the shear force and consider the relationship of capacitance changed around the sensor cell to determine the magnitude and direction of the shear force. The special design of electrodes can magnify the capacitance. The readout sensing circuit is also designed and implemented. The sensitivity is 1.56 %/mN or 28 fF/mN and the transparency is over 88 %. The tactile sensor can be applied on the touch penal and display devices. © 2011 SID.