Simulating Human Touch

March 7, 2016

The human fingertip is a complex sensing machine, and scientists have now found ways of emulating it in order to give robots a sense of touch.

Jeff Kerns

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A new tactile sensor from SynTouch performs three notable functions. First, the impedance is measured by using a flexible bladder against an array of sensing electrodes in a rigid core. This is to obtain a deformity measurement, much like the human finger uses ductile skin and flesh against a rigid bone. This is where the fingernail is needed—it causes budges in the skin that allow shear forces to be detected.

Second, micro-vibrations are registered by a pressure sensor mounted on the inside of the sensor’s core, enabling the measurement of surface roughness and texture. This is where the fingerprints add a lot of value, as they interact with textures.

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Third, in the sensor’s thermistor, the electrical resistance is dependent on temperature. The sensor (like a human finger) generates heat, and the thermistor allows their sensor to detect how it’s exchanged when it touches something.

By placing all electronics inside a rigid core and covering them with a compliant replaceable bladder, this sensor is able to function more robustly while providing sensitive human-like measurements. Electronics such as this could someday be a normal sight on robotic hands, offering a real human touch that allows a robot to identify material and grip it appropriately.