Doing surgery on some of the body’s softest tissues is like shaving a balloon without popping it: the task requires delicate movements of sharp tools. The challenge is even bigger when it’s a robot doing surgery–it can wield the tools just fine, but it runs the risk of injuring surrounding tissues, especially if organs need to be shifted or lifted in order for the tools to gain access. Moldable materials that can stiffen selectively, such as elephant trunks and snakes, could be useful for moving soft tissues and organs for less invasive procedures such as laparoscopies. With that line of thinking, a team of Italian robotics experts has built a surgical robot inspired by octopus tentacles, according to a study published today in Bioinspiration and Biomimetics.
The tool is made of three connected cylindrical chambers. Imagine the tube of a vacuum cleaner–each cylinder is hollow in the center, but the tube itself is made out of a flexible membrane filled with granules. Air can flow through the hollow chamber at the center and change its shape, and it can also be sucked out of the granule-filled membrane to stiffen it–a physical process called jamming.
In the study, the researchers tested the tool’s capabilities by having them manipulate water-filled balloons to mimic organs. The octo-arms could bend to 255 degrees and stretch up to 62 percent of their original length, deftly navigating the squishy balloons.
The findings could lead to more sophisticated surgical tools that could be operated remotely. “Traditional surgical tasks often require the use of multiple specialized instruments such as graspers, retractors, vision systems and dissectors, to carry out a single procedure,” said Tommaso Ranzani, a postdoctoral fellow at Harvard and one of the study authors, in a statement. “We believe our device is the first step to creating an instrument that is able to perform all of these tasks, as well as reach remote areas of the body and safely support organs around the target site.”