Robotic finger that feels and works like real thing

Inspired by both nature and biology, a scientist from Florida Atlantic University has designed a robotic finger that looks and feels like the real thing.

Most robotic parts used today are rigid, have a limited range of motion and do not really look lifelike.

"We have been able to thermomechanically train our robotic finger to mimic the motions of a human finger like flexion and extension," said scientist Erik Engeberg.

"Because of its light weight, dexterity and strength, our robotic design offers tremendous advantages over traditional mechanisms, and could ultimately be adapted for use as a prosthetic device, such as on a prosthetic hand," he added.

Engeberg and his team used a resistive heating process called "Joule" heating that involves the passage of electric currents through a conductor that releases heat.

With a 3D printer, they created the inner and outer moulds that housed a flexor and extensor actuator and a position sensor.

The extensor actuator takes a straight shape when it is heated, whereas the flexor actuator takes a curved shape when heated.

This new technology used both a heating and then a cooling process to operate the robotic finger. As the actuator cooled, the material relaxed slightly.

Since the initial application of this finger will be used for undersea operations, Engeberg used thermal insulators at the fingertip, which were kept open to facilitate water flow inside the finger.

As the finger flexed and extended, water flowed through the inner cavity within each insulator to cool the actuators.

The study was described in the journal Bioinspiration & Biomimetics.