A Pneumatic Anchoring Mechanism for Improved Stability in Soft Magnetic Manipulators for Surgery*

This paper presents a synergistic soft robotic actuation approach, whereby pneumatically induced anchoring is applied to a Soft Magnetic Manipulator (SMM) to enable improved post navigation stability and tip manipulation accuracy. A SMM is equipped with an integrated pneumatic expansion chamber (anchor) and tool channel to enhance stability during interventional procedures. The pneumatic anchor is tested for its position-locking effectiveness during SMM tip loading. Additionally, tip manipulation stability with and without the anchoring system activated is assessed by measurement of the SMM’s ability to trace a parametric circle using an integrated laser fiber. The anchoring mechanism showed a mean improvement in tip actuation accuracy of 73.26%. The system is further demonstrated in the case study of a brain phantom, with the prototype equipped with a laser fiber. The SMM was navigated through a brain fold through application of external magnetic fields exploiting the dual External Permanent Magnet (dEPM) platform. Upon arrival at target site, the anchor was deployed to stabilize the SMM’s tip while laser targeting was performed, demonstrating the potential of this approach for procedures requiring high precision.