Inspired by organisms that cover distance by growing – such as vines and nerve cells – the researchers say the robot represents a new kind of soft robotics that can move in ways that no known conscious being can. It has up to three chambers that, when filled with air, force extra material to unfold. By controlling the airflow in each chamber, the robot can change direction.
“The body lengthens as the material extends from the end but the rest of the body doesn't move,” said Elliot Hawkes, who developed the robot. “The body can be stuck to the environment or jammed between rocks, but that doesn’t stop the robot because the tip can continue to progress as new material is added to the end.”
It can extend into three dimensions up structures like radio antennas, lift heavy objects such as a 75kg crate, and operate valves. In future, tougher versions of the robot made of Kevlar could be used to help with search and rescue missions, helping save the lives of people stuck under rubble.
Already the prototype could hypothetically be used to help find victims in such scenarios, with the robot's vision potentially being broadcast back to human rescuers, who could then set about freeing those trapped. Even there the robot might be able to help – its ability to inflate can be used to lift heavy objects by sliding underneath them before expanding its body.
In testing, the prototype successfully navigated several contrived obstacle courses, besting flypaper and ice walls, and even survived being punctured by nails protruding from a wall.
It can also sneak through a thin gap and then expand itself on the other side in order to deploy survival tools, such as a radio communicator.
“Much like vines can transport nutrients along their length, you can imagine that a grown robot body could be used to deliver supplies and payloads or form a communication path,” said Laura Blumenschein, another of the researchers. “Or, with different material choices, you could use the grown body as a structure itself, to provide supporting forces to the environment.”
“We hope to automate manufacture of the robots so that dozens of them could cost almost nothing,” said Hawkes. He also sees potential for using it in certain types of surgery, including to guide medical catheters. He added: “We’re hoping to move to in vivo testing in the near future.”
