Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA.
Sensors (Basel). 2023 Jan 29;23(3):1510. doi: 10.3390/s23031510.
Pre-existing surgical robotic systems are sold with electronics (sensors and controllers) that can prove difficult to retroactively improve when newly developed methods are proposed. Improvements must be somehow "imposed" upon the original robotic systems. What options are available for imposing performance from pre-existing, common systems and how do the options compare? Optimization often assumes idealized systems leading to open-loop results (lacking feedback from sensors), and this manuscript investigates utility of prefiltering, such other modern methods applied to non-idealized systems, including fusion of noisy sensors and so-called "fictional forces" associated with measurement of displacements in rotating reference frames. A dozen modern approaches are compared as the main contribution of this work. Four methods are idealized cases establishing a valid theoretical comparative benchmark. Subsequently, eight modern methods are compared against the theoretical benchmark and against the pre-existing robotic systems. The two best performing methods included one modern application of a classical approach (velocity control) and one modern approach derived using Pontryagin's methods of systems theory, including Hamiltonian minimization, adjoint equations, and terminal transversality of the endpoint Lagrangian. The key novelty presented is the best performing method called prefiltered open-loop optimal + transport decoupling, achieving 1-3 percent attitude tracking performance of the robotic instrument with a two percent reduced computational burden and without increased costs (effort).
现有的手术机器人系统都配备了电子设备(传感器和控制器),当提出新的开发方法时,这些电子设备可能难以进行回溯性改进。改进必须以某种方式“强加”到原始的机器人系统上。对于强加来自现有通用系统的性能,有哪些选择?这些选择如何比较?优化通常假设理想化的系统会导致开环结果(缺乏传感器反馈),而本文研究了预滤波器的实用性,以及其他现代方法在非理想化系统中的应用,包括融合噪声传感器和所谓的“虚拟力”,这些力与旋转参考系中位移的测量有关。本文作为主要贡献比较了十几种现代方法。四种方法是理想化情况,为有效的理论比较基准建立了依据。随后,将八种现代方法与理论基准和现有的机器人系统进行了比较。两种表现最好的方法包括一种经典方法(速度控制)的现代应用,以及一种使用庞特里亚金系统理论方法推导的现代方法,包括哈密尔顿最小化、伴随方程和终点拉格朗日的终端横向性。本文提出的关键新颖之处是表现最好的方法,称为预滤波开环最优+传输解耦,该方法可以实现机器人仪器 1-3%的姿态跟踪性能,计算负担减少 2%,并且没有增加成本(工作量)。