Harvard University scientists have revealed the first-ever robot that is autonomous, untethered and made from entirely of soft parts.
The small robot, dubbed ‘octobot’ and described in an upcoming paper in the journal Nature, could open the door for a new era of totally soft, autonomous drones– revolutionizing how we think about and interact with machines.
Scientists have had trouble building totally soft robots. Electrical power and command systems – like batteries and circuit boards – are stiff and until now soft-bodied robots have been either connected to an off-board system or outfitted with hard parts.
“One long-standing vision for the field of soft robotics has been to create robots that are entirely soft, but the struggle has always been in replacing rigid components like batteries and electronic controls with analogous soft systems and then putting it all together,” team member Robert Wood, a professor of Engineering and Applied Sciences at Harvard, told redOrbit via statement. “This research demonstrates that we can easily manufacture the key components of a simple, entirely soft robot, which lays the foundation for more complex designs.”
Inspired by Nature
The new robot was inspired by octopuses, whose their incredible feats of power and dexterity without an inner skeleton have long been an inspiration for soft robotics engineers.
“Through our hybrid assembly approach, we were able to 3D print each of the functional components required within the soft robot body, including the fuel storage, power, and actuation, in a rapid manner,” said Jennifer A. Lewis, a professor of biologically-inspired engineering at Harvard. “The octobot is a simple embodiment designed to demonstrate our integrated design and additive fabrication strategy for embedding autonomous functionality.”
The octobot powered by pressurized gas. A chemical reaction inside the drone converts a small quantity of liquid fuel (hydrogen peroxide) into a large quantity of gas, which moves into the octobot’s arms and expands them like a balloon.
“Fuel sources for soft robots have always relied on some type of rigid components,” said team member Michael Wehner, a postdoctoral fellow in Wood’s lab. “The wonderful thing about hydrogen peroxide is that a simple reaction between the chemical and a catalyst — in this case platinum — allows us to replace rigid power sources.”
To manage the reaction, the team applied a microfluidic logic circuit, a cutting-edge soft analog of a basic electronic oscillator. The circuit controlled when hydrogen peroxide breaks down to gas in the octobot.
“The entire system is simple to fabricate, by combining three fabrication methods — soft lithography, molding, and 3D printing — we can quickly manufacture these devices,” said Ryan Truby, a graduate student in the Lewis lab.
The Harvard team said its next goal is to design an octobot that can creep, swim and interact with its environment.
“This research is a proof of concept,” Truby said. “We hope that our approach for creating autonomous soft robots inspires roboticists, material scientists and researchers focused on advanced manufacturing,”
Image credit: Harvard SEAS