Dexterous catheter based on multifunctional threads

Variable stiffness (VS) is an important feature that significantly enhances the dexterity of magnetic
catheters used in minimally invasive surgeries. Existing magnetic catheters with VS consist of sensors,
heaters, and tubular structures filled with low melting point alloys, which have a large stiffness change
ratio but are toxic to humans. Here, a VS magnetic catheter is described for minimally invasive surgery;
the catheter is based on a novel variable stiffness thread (VST), which is made of a conductive shape
memory polymer (CSMP). The CSMP is nontoxic and simultaneously serves as a heater, a temperature
sensor, and a VS substrate. It is made through a new scalable fabrication process.
Dario, Floreano, [e-mail], EPFL
Jun, Shintake, [e-mail], The University of Electro-Communications
Christophe, Chautems, [e-mail], ETH Zurich
Jonas, Lussi, [e-mail], ETH Zurich
Quentin, Boehler, [e-mail], ETH Zurich
Bradley, Nelson, [e-mail], ETH Zurich