Octobot – the first soft-skinned, self-powered robot

Robotics engineers are increasingly looking to nature for inspiration for their designs, with cockroaches, eels, salamanders, spiders, and stingrays all capturing their imaginations.

Now Harvard scientists have turned to one of Earth’s cleverest animals, the octopus, in a bid to capitalise on its unique strengths.

The self-powered, eight-armed device is an entirely soft robot, a trait its designers say could be able to adapt better to natural environments than those made of rigid materials.

The “octobot” is powered by chemical fuel – an aqueous solution of hydrogen peroxide – in its body that decomposes as it passes through reaction chambers containing a platinum-based catalyst. That produces pressurised oxygen, which in turn is used to expand inflatable compartments in the octobot’s arms, allowing them to move.

“The control system is roughly divided into four sections: upstream (liquid fuel storage), oscillator (liquid fuel regulation), reaction chamber (decomposition into pressurised gas) and downstream (gas distribution for actuation and venting),” the paper explains. 

The robot was constructed with a range of techniques including 3-D printing of the pneumatic networks.

In the past, soft robots have been limited by the need to be attached to hard batteries. The ability to carry its own liquid fuel changes all that.

Jennifer Lewis and colleagues report in Nature that the octobot can operate between four and eight minutes, but this run-time will improve as design and production of its components becomes more sophisticated.

“Our integrated design and rapid fabrication approach enables the programmable assembly of multiple materials within this architecture, laying the foundation for completely soft, autonomous robots,” the researchers write.