Tactile Array

Many small tactile sensing elements arranged in a grid, measuring the pressure distribution across a contact surface.

A tactile array is a sensor made of many tactile elements (taxels, each of which measures pressure at one point) arranged in rows and columns on a flexible circuit or skin. A single force sensor can only tell you the total force applied, whereas an array gives the distribution of pressure across the contact surface: where contact is happening, how large the contact area is, its shape, and where the center of force is. Common sensing principles are piezoresistive, capacitive, piezoelectric, and magnetic, typically read out by scanning row by row and column by column. Tactile arrays are commonly mounted on dexterous-hand fingertips, finger pads, and palms, or built into large-area electronic skin. Design involves trading off element density (spatial resolution), sampling rate, the number of wires, and durability. Compared with a vision-based tactile sensor that watches a gel deform through a camera, an array is thinner and easier to fit onto a curved surface, but usually has lower resolution.

ExampleA 4×4 capacitive tactile array is attached to each dexterous-hand fingertip; while grasping an egg, it shows exactly which elements the pressure concentrates on, revealing whether the egg is about to slip.

Also called

Tactile Array Sensor, Array-Type Tactile Sensor

Related

Taxel · Tactile Image · Tactile Sensor · Electronic Skin · Piezoresistive Tactile Sensing · Capacitive Tactile Sensing

Sources

Tactile Sensing—From Humans to Humanoids (Dahiya et al., IEEE T-RO 2010)