Abstract
A tactile sensing system that measures normal and shear (triaxial) forces has been developed, and its characteristics such as linearity and crosstalk have been evaluated. Triaxial forces are estimated from the resistance changes of NiCr thin film strain gauge attached to three microcantilevers. The output voltage of the Wheatstone bridge that comprises a gauge film and three reference resistances is acquired using an A/D converter after amplification. Triaxial forces are calculated from the output voltages of three microcantilevers by simple matrix multiplication. Nonlinearity and crosstalk are less than 4% when the normal force applied is up to 1N and less than 10% when the shear force applied is up to 0.2N. Active touch sensing was demonstrated using an object having a striped profile measuring 0.1mm in height and 1mm in width.
