COBRA repair robot set for human surgery

A repair robot modelled on the flexibility of snakes to access hard-to-reach places in industrial environments is now being modified for use in human surgery.

Nottingham University

Developed at Nottingham University and dubbed COBRA, the continuum robot has been demonstrated in jet engine inspection and repair, plus nuclear plant installation and maintenance.

Based in the Rolls-Royce University Technology Centre (UTC) in Manufacturing and On-Wing Technology at the University, researchers have now secured EPSRC-Impact Accelerator funding to adapt COBRA into the first robot in the UK specifically for throat cancer and injury surgery.

“We have started early tests to see if the robot can navigate and has enough motion capabilities to perform surgical procedures,” said UTC director, Professor Dragos Axinte. “For medical applications there are a lot of safety adjustments to make on the design and control method of the probe to make it suitable for inspecting inside the human body. The robot has potential in a broad range of applications and medicine is an exciting direction for our research to take.”

The 5m long robot, which is about 9mm in diameter, can be operated remotely to manoeuvre through cramped spaces and round tight bends in safety-critical machine parts where miniature scales and inhospitable locations make it physically impossible for a person to inspect or repair without fully dismantling.

This system is claimed to have extraordinary manoeuvrability and responsiveness due to a series of tendons routed along the robot snake’s ‘backbone’ - a compliant-joint structure and multiple continuous sections that enable it to bend at around 90°. When these tendons are pulled (by remote commands) it drives the bending motions – mimicking the range of movements of a human operator’s hands when handling the repair tools. The snake-arm can be different widths and has a hollow interior, through which different tools or instruments can be fitted.

Preliminary studies for COBRA’s medical use have now been carried out with Dr Oladejo Olaleye, a Consultant Ear, Nose and Throat and Robotic Surgeon at University Hospitals of Leicester NHS Trust.

COBRA was tested on a human dummy to access hard-to-reach parts at the back of the throat via the mouth - locations currently inaccessible without highly invasive surgery. A high-definition camera attached to the robot is said to have provided ‘excellent views’ of the throat displayed on an operating screen.

The robot is designed for easy manipulation and it took five minutes of training for the consultant to carry out the demonstration at the UTC laboratory. The robot was manoeuvred round bends using a hand-held drive and locked into positions in the throat to achieve optimal operating views for the surgeon.

In a statement, Dr Olaleye said: “COBRA’s strengths include a flexible construct, ability to bend and hold in position, high-definition views, ease of adaptation and portability. Achieving clear views of throat and voice-box cancers will hopefully translate into full clearance of the tumours with less pain, quicker recovery from hospital, improved survival and better rehabilitation outcomes for our patients.”

The next steps for COBRA are a series of validation studies before clinical trials take place to translate the robot’s design into medical practice.