Characterization of Crossing Profile and Insertion Force for a Soft Robotic Aortic Actuator

Sammanfattning

Heart failure remains a leading cause of death globally, driving the development of novel circulatory assist devices that can be implanted via minimally invasive surgery. This study experimentally characterizes the physical delivery constraints of a tri-chambered soft pneumatic actuator (SPA) for future transcatheter insertion. Using a digital force scale and rigid 3D-printed tubes ranging from 15 mm (45 Fr) down to 8 mm (23 Fr), the actuator was compressed using vacuum-assisted packaging and longitudinal folding. The results establish a minimum crossing profile of 9.5 mm (29 Fr). Peak insertion forces scaled non-linearly from 3.1 N at 14.7 mm up to 6.4 N at 9.5 mm, with mechanical obstruction occurring below this threshold due to the rigid proximal pneumatic supply junction. Following deployment, the actuator consistently demonstrated complete structural recovery and full inflation symmetry. These findings validate the feasibility of balancing aggressive volume reduction with reliable functional recovery, establishing design guidelines for minimally invasive extra-aortic assist technologies.