Autonomous navigation of a magnetic colonoscope using force sensing and a heuristic search algorithm

• Published in: Scientific reports Vol. 11; no. 1; pp. 16491 - 15
• Main Authors: Huang, Hao-En, Yen, Sheng-Yang, Chu, Chia-Feng, Suk, Fat-Moon, Lien, Gi-Shih, Liu, Chih-Wen
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 13.08.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 639/166/985; 692/4020/1394; 692/4020/2741/278; Algorithms; Colon; Colonoscopy; Heuristic; Humanities and Social Sciences; Intubation; Magnetic fields; multidisciplinary; Problem solving; Robotic surgery; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-95760-7

This paper presents an autonomous navigation system for cost-effective magnetic-assisted colonoscopy, employing force-based sensors, an actuator, a proportional–integrator controller and a real-time heuristic searching method. The force sensing system uses load cells installed between the robotic arm and external permanent magnets to derive attractive force data as the basis for real-time surgical safety monitoring and tracking information to navigate the disposable magnetic colonoscope. The average tracking accuracy on magnetic field navigator (MFN) platform in x-axis and y-axis are 1.14 ± 0.59 mm and 1.61 ± 0.45 mm, respectively, presented in mean error ± standard deviation. The average detectable radius of the tracking system is 15 cm. Three simulations of path planning algorithms are presented and the learning real-time A* (LRTA*) algorithm with our proposed directional heuristic evaluation design has the best performance. It takes 75 steps to complete the traveling in unknown synthetic colon map. By integrating the force-based sensing technology and LRTA* path planning algorithm, the average time required to complete autonomous navigation of a highly realistic colonoscopy training model on the MFN platform is 15 min 38 s and the intubation rate is 83.33%. All autonomous navigation experiments are completed without intervention by the operator.