Engineering news

Robotic 'octopus' arm could be used for keyhole surgery

Amit Katwala, at TechXLR8, London

Researchers in London are developing a robotic arm, inspired by the tentacles of an octopus, which can squeeze through small gaps.

It could be used for minimally invasive surgery, or for exploring behind impassable walls.

Representatives of UCL, Queen Mary University and Kings College demonstrated the technology at the TechXLR8 event, part of London Tech Week.

It’s a ‘soft robot,’ which is controlled using a combination of motors and air. “It’s a pressurised chamber with a sleeve outside that has tendons,” Andre Stuhldreher of UCL told Professional Engineering. “The tendons control the motion, and the stiffness is controlled by the pressure. We can squeeze into very narrow gaps, and once it’s behind that gap you can inflate it again.”

The technology could be fitted with a camera, or used to grip objects. It can be squeezed through gaps as small as 18mm, and can change shape depending on the amount of air pressure applied.

This opens up potential applications including surgery and exploration, according to Stuhldreher. “If you have a wall and you want to know what is behind it but the only way of accessing it is through a small gap, you can pass one of these robots through it,” he said.

Eventually, the idea would be to link a number of arms together in different configurations, depending on the task at hand. “You can do conical shapes, spiral shapes. If you get two or three you can grip stuff,” added Stuhldreher. “The gaps it can squeeze through are only constrained by the size of the fabric. Once you’ve got a small part through you can follow a sort of ‘worm’ motion. If I pass a bit through the gap I can inflate inside and it will pull the rest through.”

Jeremy Wyatt, a professor of robotics at the University of Birmingham, who was not involved in the research, said these kind soft robots were going to be “hugely important,” and had advanced a lot in recent years. A recent study by American researchers used similar technology to create a three-legged robot that could walk over unstable terrain. “It’s one way of providing physical softness, and the robots are able to be more dextrous,” said Wyatt.

"The idea behind soft robotics has been around for a number of years and draws on the way in which animals and even plants move," Helen Meese, head of healthcare at IMechE, told PE. "The octopus is such an intriguing animal and its naturally fluid movements have fascinated mechanical and robotics engineers alike for decades, but to replicate this movement has always been a challenge. New developments in silicone gel materials, chemical pneumatics and printable hydraulics are finally making this possible."

It could be a while before we see this technology in the operating theatre, however. Stuhldreher says the next step is to miniaturise the technology, as well as creating different shapes and seeing how they behave.

"Surgical robots like this octopus will be able to assist surgeons in performing complex operations, by undertaking autonomous tasks in difficult to access locations," said Meese. They have the potential to speed up the time the patient is in theatre, reducing recovery time and hospital stay as well as saving considerable money for the NHS.


Read more related articles

PE Magazine

PE app

  • Industry features and content
  • Engineering and Institution news
  • News and features exclusive to app users

Download the PE app

PE newsletter

A weekly round-up of the most popular and topical stories featured on our website, so you won't miss anything

Subscribe to the PE newsletter

Opt into your industry sector newsletter

Related articles