'Vine robots’ that possess magnetic skin are set to revolutionise how surgeons approach complex procedures, particularly in cancer diagnosis and treatment.
Inspired by the creeping movement of vine plants, these soft, slender robots can ‘grow’ and squeeze through gaps nearly 40% smaller than their resting diameter.
This unique ability allows them to navigate through the body’s narrow and intricate pathways, such as the bronchial tree in the lungs.
The robots are magnetised using silicon embedded with millions of magnetic micro-particles. They are manoeuvred with external magnets, enabling them to reach even the most challenging locations within the body.
One of the most significant advantages is the ability to move without causing friction, reducing the risk of tissue damage. This feature could lead to safer, more effective procedures, from diagnoses and biopsies to treatments, improving patient outcomes and reducing recovery times.
Engineers and scientists from the University of Leeds and the University of California, San Diego collaborated on the project led by Professor Pietro Valdastri, director of the STORM Lab at the University of Leeds.
He highlighted the potential for this technology to enhance various medical procedures, including bronchoscopy, where current tools struggle to reach most airways due to navigation challenges. The new technology could also ease the strain on healthcare systems by reducing waiting times and disease progression.
It represents a significant leap in surgical navigation technology, with potential applications extending beyond lung cancer treatment to other areas requiring delicate navigation through the body.
Pre-clinical trials are expected to conclude by the end of this year, and progress to human trials is hoped for soon.
Inspired by the plant kingdom, these robots utilise pneumatic pressure, where compressing the air inside decreases its volume while increasing its pressure. Their unique design features an inverted internal structure, similar to a partially turned inside-out sock. When a tether attached to the tip of this inside-out section is pulled, the robot contracts and becomes smaller. Releasing the tether and applying pressure from within causes the robot to extend outward, effectively growing.
This growth capability allows the robots to gently navigate collapsed tubes, creating pathways for cameras or other tools – something traditional devices can’t achieve.
The report’s lead author, Josh Davy, conducted this research during his PhD at Leeds’ School of Electronic and Electrical Engineering. He explained: ‘A surgeon pushing a catheter through the body can cause friction and discomfort, but these robots move by growing, eliminating friction. This makes it easier for them to navigate challenging pathways and reduces the risk of damaging surrounding tissue. Additionally, many cavities in the body, like those in the brain or gastrointestinal tract, are collapsed and need to be expanded for navigation. These robots can open up such collapsed tubes, which others can’t do. Once they’ve grown, they create a channel that allows the insertion of tools or cameras, offering significantly greater potential.’
The results of the team’s investigations, funded by the European Research Council, are published here.
Researchers at Leeds’ STORM Lab have also been investigating ways of controlling two magnetic robots, removing the possibility of collisions and producing the desired magnetic field to safely move the medical device inside the patient’s body.
Using a newly devised complex algorithm, the researchers have created a perfectly choreographed ‘dance’ by two robotic arms, continuously retaining a clear space between them – where a patient’s body would fit – and ensuring a consistent magnetic field.
Their innovative robotic system uses two robotic arms, each moving a large permanent magnet, to steer magnetic medical devices like the vine robots.
The unique two-step process is published in the International Journal of Robotics Research.
