Sequential Tool Feeding System via Modular Hydraulic Ring-Shaped Soft Actuator

Abstract

This paper presents a soft robotic tool feeding mechanism based on hydraulic-driven ring-shaped actuators that provide compliant yet controllable gripping and incremental tool advancement. The system is broadly applicable to tool feeding tasks in confined or sensitive environments, with minimally invasive procedures serving as a representative example where precise and adaptable insertion is critical. By tuning structural constraints and material hardness, the actuator's force transmission and positional accuracy can be adjusted to balance flexibility with control. Experimental evaluation demonstrates how these design choices influence gripping performance, feeding repeatability, and generalizability to tools of varying diameters. The proposed approach offers a compact, MRI-compatible alternative to conventional rigid feeding mechanisms and highlights the potential of inward-deforming membrane actuators for safe and customizable instrument handling.