CPS: Breakthrough:Towards Resiliency in Cyber-physical Systems for Robot-assisted Surgery

自2000年以来，手术机器人已经在美国的各种外科专业中应用了超过175万例微创手术，包括妇科、泌尿外科、普通外科、心胸外科和头颈部外科。由于手术的微创性，机器人手术有望降低并发症发生率和发病率。与手术机器人相关的不良事件的详细分析（也报告给FDA）表明，尽管机器人手术的数量增加，它们的使用率更高，但在过去的14年中，不良事件的发生率保持相对稳定。尽管目前的手术机器人在设计时考虑了安全机制，但在实践中，在及时准确地检测和减轻手术过程中的不良事件方面存在一些重大挑战。为了实现这一目标，该项目将解决以下问题：(i)对事故原因进行深入分析，其中考虑到系统组件、操作人员和患者之间的相互作用；（ii）机器人系统在现实安全隐患、可靠性故障和恶意篡改情况下的弹性评估；（三）持续监测检测安全性、可靠性和安全违规行为，以确保患者安全。这项工作的智力优势在于：(i)由安全危害和医疗设备召回的真实数据驱动的系统理论方法，以确定导致违反网络和物理系统控制结构不同层的安全约束的原因；（ii）创建一个独特的安全隐患模拟引擎，在机器人控制软件中进行注入，并在虚拟环境中模拟现实的安全隐患场景；（iii）一种快速检测导致安全违规事件的自适应方法，该方法基于对人类操作员行为、机器人状态和患者状态的持续监测，并结合捕获导致安全危害的因果因素之间依赖关系的概率图模型；（iv）使用真实机器人进行实验验证，以评估存在现实安全隐患，可靠性故障和安全漏洞的监测和保护机制（使用安全隐患模拟引擎重新创建）。该项目的更广泛影响是为更大类控制网络物理系统的设计和弹性评估提供一种方法，其中涉及在线决策循环中的人类。该方法在机器人辅助手术中的应用证明了该方法的强度和实用性，并可能吸引学术界和工业界的兴趣，其中网络物理系统要么是研究的主题，要么是提供服务的基础（例如，交通或电网）。这个项目的教育外展包括扩大参与跨医学和工程的多学科项目的策略。

Since 2000, surgical robots have been used in over 1.75 million minimally invasive procedures in the U.S. across various surgical specialties, including gynecological, urological, general, cardiothoracic, and head and neck surgery. Robotic surgical procedures promise decreased complication rates and morbidity, due to the minimally invasive nature of the procedures. A detailed analysis (also reported to the FDA) of the adverse events associated with the surgical robot indicates that despite the increased number of robotic procedures and their greater utilization, the rate of adverse events has remained relatively steady over the last 14 years. Even though current surgical robots are designed with safety mechanisms in mind, in practice several significant challenges exist in enabling timely and accurate detection and mitigation of adverse incidents during surgery. Toward this goal, the project will address (i) an in-depth analysis of incident causes, which takes into account the interactions among the system components, human operators, and patients; (ii) resiliency assessment of the robotic systems in the presence of realistic safety hazards, reliability failures, and malicious tampering; and (iii) continuous monitoring for detection of safety, reliability, and security violations to ensure patient safety.The intellectual merit of this work lies in: (i) systems-theoretic approach driven by real data on safety hazards and medical equipment recalls, to identify causes leading to violation of safety constraints at different layers of the cyber and physical system-control-structure; (ii) creation of a unique safety hazard simulation engine to perform injections into robot control software and emulate realistic safety hazard scenarios in a virtual environment; (iii) an adaptive method for rapid detection of events that lead to safety violations, based on continuous monitoring of human operator actions, robot state, and patient status, in conjunction with a probabilistic graph-model that captures dependencies between the causal factors leading to safety hazards; and (iv) experimental validation using the real robot to assess monitoring and protection mechanisms in the presence of realistic safety hazards, reliability faults, and security exploits (recreated using safety hazard simulation engine). The broader impact of the project is a methodology for design and resiliency assessment of a larger class of control cyber-physical systems, which involve humans in the on-line decision making loop. Application of the methodology to robot-assisted surgery demonstrates the strength and practicality of the approach and is likely to attract interest from areas of academia and industry in which cyber-physical systems are either a subject of study or the basis for delivering a service (e.g., transportation or electric power grids). This project's educational outreach encompasses strategies for broadening participation in multi-disciplinary projects spanning medicine and engineering.