Systematic Characterization of Drilling Parameters in Concentric Tube Steerable Drilling Robots: A Comparative Study
Daniyal Maroufi, Yash Kulkarni, Vibhu Kanna Rajesh Kanna, Jordan P. Amadio, Mohsen Khadem, Justin E. Bird, Jeff Siewerdsen, Farshid Alambeigi
Abstract
To establish a foundational understanding for creating J-shaped trajectories with Concentric Tube Steerable Drilling Robots (CT-SDRs), this paper presents a systematic characterization of two operational factors: drill feed rate and rotational speed. We developed and compared a custom High-Speed Drill (HSD) and a Low-Speed Drill (LSD) to analyze how these parameters affect performance in flexible robotic drills versus conventional systems utilizing rigid instruments. By integrating the CT-SDRs with a seven degree-of-freedom robotic manipulator, we conducted experiments in synthetic bone phantoms of varying densities, assessing metrics such as motor current, hole diameter, radius of curvature, and drilling time. The results reveal critical performance trade-offs, demonstrating that high-speed drilling in CT-SDRs is essential for successfully penetrating dense bone. Further, we found that while slower feed rates improve trajectory accuracy and reduce hole enlargement, they significantly increase procedural time. These findings offer a quantitative guideline for design choices, component selection, and operational control of CT-SDRs tailored to patient-specific bone quality.