Seddaoui Asma, Saaj Chakravarthini Mini, Nair Manu Harikrishnan
Surrey Space Centre, Department of Electronic and Electrical Engineering, University of Surrey, Guildford, United Kingdom.
Lincoln Centre for Autonomous Systems (L-CAS), University of Lincoln, Lincoln, United Kingdom.
Front Robot AI. 2021 Dec 24;8:725333. doi: 10.3389/frobt.2021.725333. eCollection 2021.
Ground-based applications of robotics and autonomous systems (RASs) are fast advancing, and there is a growing appetite for developing cost-effective RAS solutions for servicing, debris removal, manufacturing, and assembly missions. An orbital space robot, that is, a spacecraft mounted with one or more robotic manipulators, is an inevitable system for a range of future in-orbit services. However, various practical challenges make controlling a space robot extremely difficult compared with its terrestrial counterpart. The state of the art of modeling the kinematics and dynamics of a space robot, operating in the free-flying and free-floating modes, has been well studied by researchers. However, these two modes of operation have various shortcomings, which can be overcome by operating the space robot in the controlled-floating mode. This tutorial article aims to address the knowledge gap in modeling complex space robots operating in the controlled-floating mode and under perturbed conditions. The novel research contribution of this article is the refined dynamic model of a chaser space robot, derived with respect to the moving target while accounting for the internal perturbations due to constantly changing the center of mass, the inertial matrix, Coriolis, and centrifugal terms of the coupled system; it also accounts for the external environmental disturbances. The nonlinear model presented accurately represents the multibody coupled dynamics of a space robot, which is pivotal for precise pose control. Simulation results presented demonstrate the accuracy of the model for closed-loop control. In addition to the theoretical contributions in mathematical modeling, this article also offers a commercially viable solution for a wide range of in-orbit missions.
机器人技术和自主系统（RAS）的地面应用正在迅速发展，人们越来越希望开发具有成本效益的RAS解决方案，用于服务、碎片清除、制造和装配任务。轨道空间机器人，即搭载一个或多个机器人操纵器的航天器，是未来一系列在轨服务中不可或缺的系统。然而，与地面机器人相比，各种实际挑战使得控制空间机器人极其困难。研究人员已经对自由飞行和自由漂浮模式下运行的空间机器人的运动学和动力学建模的技术水平进行了深入研究。然而，这两种操作模式存在各种缺点，通过在受控漂浮模式下操作空间机器人可以克服这些缺点。本教程文章旨在填补在受控漂浮模式和受扰条件下运行的复杂空间机器人建模方面的知识空白。本文的新颖研究贡献是一个追踪空间机器人的精确动态模型，该模型是相对于移动目标推导出来的，同时考虑了由于耦合系统的质心、惯性矩阵、科里奥利力和离心项不断变化而产生的内部扰动；它还考虑了外部环境干扰。所提出的非线性模型准确地表示了空间机器人的多体耦合动力学，这对于精确的姿态控制至关重要。给出的仿真结果证明了该模型用于闭环控制的准确性。除了在数学建模方面的理论贡献外，本文还为广泛的在轨任务提供了一种商业上可行的解决方案。
