A SILICON-BASED TACTILE SENSOR FOR FINGER-MOUNTED APPLICATIONS

This paper presents a silicon-based force sensor packaged in a flexibl e package and describes the sensors performance on human subjects, The sensing element consists of a circular silicon diaphragm (200-mu m th ick with a 2-mm radius) over a 10-mu m sealed cavity with a solid Torl on dome providing force-to-pressure transduction to the diaphragm, Two dome heights (0.5 and 1.5 mm) were compared, The sensor with the tall er dome showed improved sensitivity, Dynamic calibration and tracking experiments are performed with the sensor mounted on the dominant thum b of five human subjects, Both force and loading direction are statist ically significant (P < 0.05), Subject variability accounted for 8.7% of the variance, while loading direction accounted for 1.9% of the var iance, Average errors for the tracking experiment range from -2.8 to 1 .0 N and are subject dependent, Three out of four subjects showed incr easing negative error with increasing load.