Abstract
This paper discloses the recent advancements in capacitive tactile sensors (CTSs) that are mostly composed of polymeric materials. Six advancements of functionality, angular resolution, spatial resolution, sensitivity, tolerance suppression, and operation range are described. The add-on function of a CTS that supports normal and shear force detection is introduced based on the expansion of capacitances used in a sensing unit; the angular resolution of a CTS that distinguishes the shear force applied along a specific angle in the xy-plane is explained based on an intentional electrode misalignment; the spatial resolution improvement of the CTS is explained with compact arrangement of the capacitors in a sensing unit; the sensitivity enhancements in both normal and shear force detection are explained with the lowered material and structural rigidity; the suppression of detection tolerance generated during fabrication is explained by a universal solution of electrode shape modulation; and the working range expansion of a CTS is concluded with the introduction of additional stopper structure.