Soft robotics: how vine-like robots are transforming tumor treatment

In our latest Lexicon episode , we sit down with Professor Pietro Valdastri , a robotics and autonomous systems leader at the University of Leeds. We explored his team’s cutting-edge work on soft magnetic robots that mimic vine plants.

As you are about to find out, these robots have the potential to transform how we diagnose and treat some of the most challenging medical conditions, including cancer.

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Why build robots inspired by vines?

The concept of a vine plant growth-inspired robot is unconventional, but there is logic to the apparent madness. The concept is ideal for solving practical challenges surgeons and clinicians face when navigating the human body.

“The original idea of these growing robots comes from Stanford. They developed a larger-scale robot to explore unstructured environments. What we added was the magnetic steering, the magnetic direction, Valdastri explained to IE.

To this end, the robots developed by Valdastri and his team grow from within, allowing them to move through the body’s narrowest passages without traditional pushing or pulling mechanisms, which can damage tissue.

“Instead of having a mechanism inside the robot to steer and move the tip left, right, up, or down, we use magnetic fields,” he explains. “This allows us to reduce the robot’s size because we don’t need internal cables or actuators,” he added.

Under the hood

Valdastri explained that the robots work via a combination of pneumatic pressure, which powers the robot’s growth, and magnetic particles embedded in its skin. This makes the robot’s movement both gentle and precise.

“The robot’s body is soft, made of silicone, but also has magnetic particles,” says Valdastri. “These particles can be directed by an external permanent magnet connected to a robotic arm. So, as the robot advances through, say, the bronchial tree, we steer it using the magnetic fields when we reach a bifurcation or need to turn,” he added.

This ability to steer the robot remotely through magnetic fields offers many advantages over traditional endoscopy tools, which are often rigid and have limited maneuverability. In contrast, the vine robot’s flexibility and growth method allow it to travel through highly complex, winding structures deep within the body.

Reduced risk, greater precision

One of the most promising applications of these robots is in lung cancer diagnosis and treatment. Traditional bronchoscopes that navigate the bronchial tree can only reach the third bifurcation, leaving large portions of the lungs unexplored.

“With current flexible endoscopes, we can only reach after the third bifurcation,” Valdastri explains. “The bronchial tree gets smaller and smaller, making it difficult to reach the periphery of the lungs, where tumors are often located,” he added.

However, the magnetic vine robot makes reaching these hard-to-access areas feasible. “We hope to get to the periphery of the lungs, and there deploy treatment or take biopsies,” says Valdastri.

This could significantly improve the detection and treatment of tumors in areas currently out of reach for standard medical tools. What’s more, the robot’s soft body minimizes the risk of damaging delicate tissues during procedures.

“It’s safer because we’re not pushing a rigid tube inside the body,” Valdastri emphasized. “We’re growing a soft robot from within, which means less trauma to the tissue. In some cases, we believe it could even be painless,” he added.

Many applications in the body

While the vine-inspired robot shows great promise for lung cancer treatment, its potential applications extend to other areas of the body. Valdastri’s team is also exploring using them for neurosurgery and navigating the small intestine.

“In the brain, the anatomy is very delicate, and being able to grow the robot without disrupting the tissue is crucial,” Valdastri notes. “The magnetic vine robot could allow us to navigate the brain in a soft, flexible way, avoiding the need for straight pathways,” he added.

Current medical technologies also fail in the small intestine. “Reaching the small intestine with traditional tools is very difficult and often requires full sedation,” he says. This technology could allow us to get there in a much less invasive way,” he told IE.

Still many hurdles to overcome

Despite its immense potential, the vine-inspired robot still needs to overcome technical challenges before it can be widely adopted.

“One of the main challenges is localization,” Valdastri explains. “Magnetic fields are extremely non-linear in space, so it’s hard to control if you don’t know where the robot is inside the body. We’re improving our techniques for localizing the robot and adjusting the external magnet accordingly,” he added.

Another challenge lies in miniaturization. While the team has already developed robots as small as three millimeters, making them even smaller could unlock more applications.

“The advantage of using magnetic fields is that we can make the robot as small as possible, which allows us to go deeper into the body,” Valdastri says. “But further miniaturization requires advanced manufacturing techniques, which we’re continually working on,” he said.

Looking ahead

While still in the early stages of development, Valdastri and his team are already making significant progress toward clinical use.

“For bronchoscopy, we’re at the stage of cadaver trials,” Valdastri explained. “We’re testing our technology in human lungs donated by people who have passed away. For neurosurgery and the small intestine, we’re a step behind. We are still working on simulators, but we hope to move to animal trials soon,” he added.

But, as Valdastri explained, the main constraint on the robot’s future (especially for human trials) depends mainly on funding and support.

“Typically, getting a new medical technology like this to human trials takes about five years,” Valdastri explains. “It all depends on the level of support we can secure. We’re discussing with the NHS and other medical institutions to accelerate the process,” he said.

The potential of soft, magnetic robots like those developed by Valdastri’s team is vast. In addition to improving patient outcomes in cancer treatment, these robots could reduce recovery times, minimize surgical risks, and make procedures less painful for patients.

“It’s a transformative technology,” Valdastri concludes. “We’re not just improving the tools doctors use—we’re changing the way we think about medical procedures altogether,” he added,

As this groundbreaking research moves closer to clinical reality, it’s clear that soft robotics will play an increasingly important role in the future of healthcare. By making even the most inaccessible parts of the human body navigable, these robots offer hope for more effective, less invasive treatments for cancer and beyond.