Towards Semi-Autonomous Colon Screening Using an Electromagnetically Actuated Soft-Tethered Colonoscope Based on Visual Servo Control.

OBJECTIVE: Conventional colonoscopy using a flexible colonoscope remains two major limitations, including patient discomfort and difficult manipulations for surgeons. Robotic colonoscopes have been developed to conduct colonoscopy in a patient-friendly manner. However, most robotic colonoscopes still maintain nonintuitive and difficult manipulations, which limits their clinical applications. In this paper, we demonstrated visual servo-based semi-autonomous manipulations of an electromagnetic actuated soft-tethered (EAST) colonoscope, which aims to lower difficulties of robotic colonoscope manipulations. METHODS: Kinematic modeling of EAST colonoscope is conducted, with an adaptive visual servo controller established. Template matching method and a lumen and polyp detection model are developed to enable semi-autonomous manipulations, including region-of-interest automatic tracking and autonomous navigation with automatic polyp detection. RESULTS: The EAST colonoscope demonstrates visual servoing with an average convergence time of around 2.5 s and performs disturbance rejection within 3.0 s. Semi-autonomous manipulations were conducted in both a commercialized colonoscopy simulator and an ex-vivo porcine colon to show the efficacy of reducing the user workload compared to manual control. CONCLUSION: The EAST colonoscope can perform visual servoing and semi-autonomous manipulations with the developed methods in both laboratory and ex-vivo environments. SIGNIFICANCE: The proposed solutions and techniques improve the autonomy level of robotic colonoscopes and reduce user workloads, which promotes the development and clinical translation of robotic colonoscopy.

A Semi-Autonomous Stereotactic Brain Biopsy Robotic System With Enhanced Surgical Safety and Surgeon-Robot Collaboration.

OBJECTIVE: Despite benefits brought by recent neurosurgical robots, surgical safety and surgeon-robot collaboration remain significant challenges. In this article, we analyze and address these problems in the context of brain biopsy, by proposing a semi-autonomous system. METHODS: A robotic module is designed for the automation of all the brain biopsy procedures, and a biopsy cannula with tissue blocker is developed to avoid tissue excess and haemorrhage. In addition, two methods are proposed for surgical safety and surgeon-robot collaboration enhancement. First, a priority-based control framework is proposed for neuronavigation with simultaneous optical tracking line-of-sight maintenance and surgeon avoidance. Second, after neuronavigation, an adaptive reconfiguration method is developed to optimize the arm angle of KUKA robot based on the surgeon's pose, for workspace interference minimization, high robot dexterity, and joint-limit avoidance. RESULT: Effectiveness of the proposed solution demonstrated by simulations and experiments. CONCLUSION: The system can perform automatic navigation with simultaneous optical tracking maintenance and surgeon avoidance, autonomous brain biopsy, and adaptive reconfiguration for workspace interference minimization. SIGNIFICANCE: This work improves existing neurosurgical systems, in terms of autonomy level from mechanical guidance to task autonomy, surgical safety, and surgeon-robot collaboration.