Scientists have developed a magnetic control system that can independently guide multiple miniature robots through complex three-dimensional vessel networks, potentially enabling simultaneous treatment of multiple disease sites within the body.
Researchers at the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart have created a robotic system capable of deploying and controlling multiple five-millimetre-sized robots within a three-dimensional matrix that mimics blood vessels. The innovation, published in Science Advances on 6 November 2024, represents a significant step forward in the field of minimally invasive medical procedures.
Clinical implications for stroke treatment
The development holds particular promise for conditions such as stroke, where multiple blocked blood vessels can simultaneously deprive different brain regions of oxygen, leading to rapid cellular damage. Current treatment approaches often struggle with addressing multiple affected sites quickly enough to prevent permanent neurological damage.
The system’s ability to deploy several robots simultaneously could substantially reduce procedure times in such critical scenarios. Each magnetic robot, designed in the form of a stent, can flexibly adapt to changes in vessel structure while carrying out functions such as drug delivery or flow diversion.
Technical advancement in magnetic control
The research team has overcome a fundamental challenge in magnetic robot control: the ability to manipulate multiple magnetic objects independently within the same magnetic field. “To our knowledge, this is the first case of independent control of more than five robots in 3D lumens under physiologically relevant conditions,” says Chunxiang Wang, a PhD student at MPI-IS and first author of the study.
The system employs a rotating permanent magnet with specifically designed influence and rotation regions to enhance usability. By carefully positioning the magnet, operators can selectively activate or deactivate specific robots. The control system has been designed with clinical practicality in mind, featuring an automated path-planning algorithm that allows users to simply input target points, with a robotic arm handling the complex navigation calculations.
“For us it was quite a challenge to control multiple magnetic robots all at once – after all, all magnetic parts are affected by the magnetic field in the same way,” explains Tianlu Wang, former postdoctoral researcher at MPI-IS and currently Assistant Professor at the University of Hawaii at Manoa.
Future applications
According to Metin Sitti, former Director of the Physical Intelligence Department at MPI-IS and President at Koç University: “The proposed system has the potential to open avenues for a wide range of biomedical applications by deploying a group of soft robots equipped with diverse functional modules to reach hard-to-access areas deep inside the human body for targeted therapy”.
The technology could particularly benefit procedures requiring simultaneous intervention at multiple sites, such as complex vascular conditions or distributed drug delivery requirements. The system’s ability to navigate through tortuous vessels while maintaining precise control over multiple robots represents a significant advancement in minimally invasive therapeutic approaches.
Reference:
Wang, C., Wang, T., Li, M., et. al. (2024). Heterogeneous multiple soft millirobots in three-dimensional lumens. Science Advances. https://doi.org/10.1126/sciadv.adq1951
