A new eight-armed robot’s rhythmic, tentacle-flailing dance routine is so awkwardly cute that you might not immediately grasp the engineering feat achieved by the octopus mimic.
Dubbed the “octobot,” it is the first robot to be self-propelled, untethered, and made entirely from soft materials (Nature 2016, DOI: 10.1030/nature19100). All previous robots have either had some rigid components or they’ve been attached to a rigid system, explains Harvard University’s Jennifer A. Lewis, who, along with colleague Robert J. Wood, led the team that built the machine.
The achievement helps pave the way for soft robots that can perform search-and-rescue operations and exploration or devices that can be put to work as soft endoscopes in biomedical applications, note Barbara Mazzolai and Virgilio Mattoli of the Center for Micro-BioRobotics in an associated commentary (Nature 2016, DOI: 10.1038/536400a). “Robots made from soft, deformable materials would be better able to grasp and manipulate unknown objects, and to move on unstructured and rough terrains, and might be less hazardous to people,” they add.
Lewis and colleagues made the octobot using a combination of 3-D printing, molding, and soft lithography. Hydrogen peroxide fuels the robot: When the chemical, encapsulated within the machine’s core, comes in contact with a platinum catalyst in a reaction chamber, the hydrogen peroxide breaks down into oxygen gas and water vapor that power the robot’s tentacle motions. Microfluidic logic circuits direct this gas into four of the octobot’s arms at a time, moving half the tentacles out and up with pneumatic pressure. The sequence is then repeated with the octobot’s remaining four tentacles so that every other arm of the robot is either up or down at any given time.
This motion “is a very minimalist embodiment of our concept,” Lewis says. “But it’s a sea change for what could be done,” she adds.