Flexible silicon triaxial tactile imager with integrated 800µm-pitch sensor pixel structures on a diaphragm

In this paper, a silicon integrated triaxial tactile imager with 800µm-pitch sensor pixel circuits and its real-time demonstration of slipping motion detection are presented for the first time. Distributions of normal- and shear-force components on contacting object surface are independently detected by the triaxial micro force sensor pixels on a flexible silicon diaphragm. The minimum force resolutions of each triaxial force sensor are below 5mN, and the cross-axis errors are below 3%. The new device structure of triaxial tactile imager can cope with both high spatial/force resolution and high adaptability to the object surface. Also, the beginning point of slipping can be specified by the individually formed fingerprint structures on the high-density multi-axis force sensor circuits. This is the first triaxial tactile imager which can be compared with human fingertip functions on the sensing performance of slip detection.