Task Autonomy of a Flexible Endoscopic System for Laser-Assisted Surgery

Laser beam steering has been widely studied for the automation of surgery. Currently, flexible instruments for laser surgery are operated entirely by surgeons, which keeps the automation of endoluminal surgery at the initial level. This paper introduces the design of a new workflow that enables the task autonomy of laser-assisted surgery in constrained environments such as the gastrointestinal (GI) tract with a flexible continuum robotic system. Unlike current, laser steering systems driven by piezoelectric require the use of high voltage and are risky. This paper describes a tendon-driven 2 mm diameter flexible manipulator integrated with an endoscope to steer the laser beam. By separating its motion from the total endoscopic system, the designed flexible manipulator can automatically manipulate the laser beam. After the surgical site is searched by the surgeon with a master/slave control, a population-based model-free control method is applied for the flexible manipulator to achieve accurate laser beam steering while overcoming the noise from the visual feedback and disturbances from environment during operation. Simulations and experiments are performed with the system and control methods to demonstrate the proposed framework in a simulated constrained environment.

A Finite-Time Trajectory-Tracking Method for State-Constrained Flexible Manipulators Based on Improved Back-Stepping Control

In order to solve the trajectory-tracking-control problem of the state-constrained flexible manipulator systems, a finite-time back-stepping control method based on command filtering is presented in this paper. Considering that the virtual signal requires integration in each step, which will lead to high computational complexity in the traditional back-stepping, the finite-time command filter is used to filter the virtual signal and to obtain the intermediate signal in finite time, to thus reduce the computational complexity. The compensation mechanism is used to eliminate the error generated by the command filter. Furthermore, the adaptive estimation method is introduced to approach the uncertainty of the state-constrained flexible manipulator system. Then, the Lyapunov function is used to prove that the tracking error of the system can be stabilized in a sufficiently small origin neighborhood within a finite time. The simulation of a single rod flexible manipulator system demonstrates the effect of the proposed approach.

A Dexterous Robotic System for Autonomous Debridement of Osteolytic Bone Lesions in Confined Spaces: Human Cadaver Studies

This article presents a dexterous robotic system for autonomous debridement of osteolytic bone lesions in confined spaces. The proposed system is distinguished from the state-of-the-art orthopedics systems because it combines a rigid-link robot with a continuum manipulator (CM) that enhances reach in difficult-to-access spaces often encountered in surgery. The CM is equipped with flexible debriding instruments and fiber Bragg grating sensors. The surgeon plans on the patient's preoperative computed tomography and the robotic system performs the task autonomously under the surgeon's supervision. An optimization-based controller generates control commands on the fly to execute the task while satisfying physical and safety constraints. The system design and controller are discussed and extensive simulation, phantom and human cadaver experiments are carried out to evaluate the performance, workspace, and dexterity in confined spaces. Mean and standard deviation of target placement are 0.5 and 0.18 mm, and the robotic system covers 91% of the workspace behind an acetabular implant in treatment of hip osteolysis, compared to the 54% that is achieved by conventional rigid tools.

A Confidence-Based Supervised-Autonomous Control Strategy for Robotic Vaginal Cuff Closure

Autonomous robotic suturing has the potential to improve surgery outcomes by leveraging accuracy, repeatability, and consistency compared to manual operations. However, achieving full autonomy in complex surgical environments is not practical and human supervision is required to guarantee safety. In this paper, we develop a confidence-based supervised autonomous suturing method to perform robotic suturing tasks via both Smart Tissue Autonomous Robot (STAR) and surgeon collaboratively with the highest possible degree of autonomy. Via the proposed method, STAR performs autonomous suturing when highly confident and otherwise asks the operator for possible assistance in suture positioning adjustments. We evaluate the accuracy of our proposed control method via robotic suturing tests on synthetic vaginal cuff tissues and compare them to the results of vaginal cuff closures performed by an experienced surgeon. Our test results indicate that by using the proposed confidence-based method, STAR can predict the success of pure autonomous suture placement with an accuracy of 94.74%. Moreover, via an additional 25% human intervention, STAR can achieve a 98.1% suture placement accuracy compared to an 85.4% accuracy of completely autonomous robotic suturing. Finally, our experiment results indicate that STAR using the proposed method achieves 1.6 times better consistency in suture spacing and 1.8 times better consistency in suture bite sizes than the manual results.

Review of Advanced Medical Telerobots

The advent of telerobotic systems has revolutionized various aspects of the industry and human life. This technology is designed to augment human sensorimotor capabilities to extend them beyond natural competence. Classic examples are space and underwater applications when distance and access are the two major physical barriers to be combated with this technology. In modern examples, telerobotic systems have been used in several clinical applications, including teleoperated surgery and telerehabilitation. In this regard, there has been a significant amount of research and development due to the major benefits in terms of medical outcomes. Recently telerobotic systems are combined with advanced artificial intelligence modules to better share the agency with the operator and open new doors of medical automation. In this review paper, we have provided a comprehensive analysis of the literature considering various topologies of telerobotic systems in the medical domain while shedding light on different levels of autonomy for this technology, starting from direct control, going up to command-tracking autonomous telerobots. Existing challenges, including instrumentation, transparency, autonomy, stochastic communication delays, and stability, in addition to the current direction of research related to benefit in telemedicine and medical automation, and future vision of this technology, are discussed in this review paper.

The evolution of lower gastrointestinal endoscopy: where are we now?

Lower gastrointestinal endoscopy has evolved over time, fulfilling a widening diagnostic and therapeutic remit. As our understanding of colorectal cancer and its prevention has improved, endoscopy has progressed with improved diagnostic technologies and advancing endoscopic therapies. Despite this, the fundamental design of the endoscope has remained similar since its inception. This review presents the important role lower gastrointestinal endoscopy serves in the prevention of colorectal cancer and the desirable characteristics of the endoscope that would enhance this. A brief history of the endoscope is presented. Current and future robotic endoscopic platforms, which may fulfil these desirable characteristics, are discussed. The incorporation of new technologies from allied scientific disciplines will help the endoscope fulfil its maximum potential in preventing the increasing global burden of colorectal cancer. There are a number of endoscopic platforms under development, which show significant promise.