Measuring the Moment-Curvature Relationship of a Steerable Catheter Using a Load Cell and Stereovision System

Accurately positioning the tip of steerable catheters is crucial for effective catheter-based operations. This requires an understanding of the moment-curvature relationship of a catheter. However, determining this relationship using traditional methods is challenging due to catheters’ multi-material and segmented structure. This study introduces a method for determining the moment-curvature relationship of each segment of the steerable catheter by using a load cell and stereovision system. The load cell and stereo camera are utilized to collect moment and curvature data, respectively, over time. An algorithm to detect the catheter from images is developed, and the procedure of getting the curvature of each segment is demonstrated. The moment-curvature relationship is plotted as the moment changes with time. The reliability of stereo camera is verified showing error less than 4 mm, and the algorithm successfully detects the curvature of the catheter by segments. This study offers a tool to measure steerable catheters’ material properties, and ultimately enhances catheter-based interventions’ precision.