Thermally Drawn Steerable Soft Robotic Fiber for Multi-Purpose Minimally Invasive Surgery

Soft robotic instruments offer unique advantages for minimally invasive surgery (MIS), including safe tissue interaction and adaptability within confined anatomical spaces. However, achieving both miniaturization and functionality within a single device remains a significant engineering challenge. This work presents a monolithically fabricated, tendon-driven fiber robot produced via thermal drawing, integrating rigid polycarbonate (PC) and compliant Styrene-Ethylene-Butylene-Styren (SEBS) elastomer into a continuous, multi-lumen structure. The resulting platform enables remote steering of the fiber tip while supporting channels for additional diagnostic or therapeutic functions. Three purpose-specific fiber variants were developed and evaluated in anatomical phantoms: transvaginal tumor ablation requiring high-precision motion control, gastrointestinal optical diagnosis with spectroscopic sensing, and endovascular navigation with targeted liquid delivery. These demonstrations validate the robot's precision, adaptability, and clinical relevance across multiple MIS scenarios. The proposed thermally drawn fiber offers a scalable approach for rapid prototyping and development of compact, multi-purpose medical devices.