A new generation of medical robots, inspired by nature, promises to navigate the most remote recesses of the human body. Their flexible design and magnetic guidance open up unprecedented prospects for minimally invasive interventions.
These devices, developed by a team from the University of Macau, represent a potential advance for the diagnosis and treatment of digestive pathologies. They aim to overcome the limitations of conventional endoscopes, which are often perceived as uncomfortable by patients and have a limited reach.
Inspiration from the desert
The locomotion principle of these robots is directly inspired by a particular spider, the
Carparachne aureoflava. This specimen, native to the Namibian dunes, uses a rolling motion to quickly escape its predators on unstable terrain. Engineers have transposed this efficient natural mechanism into an artificial device.
Schematic illustration of the bio-inspired soft magnetic robots and their applications in the biomedical field. These 'spiders' are manipulated by a robotic arm with six degrees of freedom to generate rotating magnetic fields. They can crawl on inclined surfaces (including moving upside down) and navigate within the digestive tract. The robot's structure is entirely designed from soft and biocompatible materials. This flexibility is essential to avoid damaging the delicate walls of the digestive tract during its movement. The risk of injury to internal tissues is thus significantly reduced.
The device is controlled from outside the body using a magnetic field generated by robotic equipment. This system offers great movement precision with six degrees of freedom. The robot can then be piloted very smoothly through the organs.
All-direction navigation in the digestive system
The ability to move on vertical surfaces, or even upside down, is one of the major assets of this technology. This omnidirectional mobility is useful for inspecting areas such as the folds of the stomach or the walls of the colon. The robot overcomes significant height differences, which can reach several centimeters (over an inch).
The system's effectiveness has been validated during tests under realistic conditions, performed on animal digestive tract segments. The results, published in the
International Journal of Extreme Manufacturing, confirm the robots' ability to reach specific targets. They also demonstrate successful navigation in mucus-covered environments.
In the long term, these robots could be equipped with micro-cameras or reservoirs to deliver active ingredients in a highly localized manner. This targeted approach could be applied to the treatment of precancerous lesions or localized tumors. The path is open towards much less invasive interventions.
To go further: What are the current limitations of traditional endoscopy?
Standard endoscopy uses a long flexible tube equipped with a light and a camera. Its insertion can be uncomfortable, often requiring patient sedation. The relative rigidity of the device limits its access to the most winding areas of the small intestine.
The precision of the medical procedure can also be constrained by the shape of the endoscope. Movements are sometimes less fine than desired for very localized sample collection or drug administration. The field of view remains limited by the configuration of the tube's tip.
Furthermore, the procedure can carry risks, albeit low, of perforating the digestive wall. These limitations stimulate the search for more precise and better-tolerated alternative solutions. New robotic technologies aim directly to address these drawbacks.
Article author: Cédric DEPOND