The new era of walking manipulators in space: Feasibility and operational assessment of assembling a 25 m Large Aperture Space Telescope in orbit

Robotics, Automation, and Autonomous Systems form the cornerstone for ambitious large-scale in-orbit missions. However, the harsh space environment presents unique challenges that demand careful consideration. Key requirements for next-generation space manipulators include dexterity, modularity, redundancy, workspace enhancement, and autonomous mobility. To address the limitations of conventional walking manipulators, this paper presents a novel seven-degrees-of-freedom dexterous End-Over-End Walking Robot (E-Walker) for future In-Space Assembly and Manufacturing missions. The use-case considers the in-situ robotic assembly of the primary mirror of a 25 m Large Aperture Space Telescope (LAST). This research is timely given the constant clamour for high-resolution astronomy and earth observation within the space community and serves as a baseline for future missions with telescopes of much larger aperture, missions requiring assembly of space stations, and solar-power generation satellites to list a few. The paper starts by eliciting the mission Concept of Operations (ConOps) for the in-situ assembly of a 25 m LAST utilising the next-generation E-Walker space manipulator, which serves as a narrative backdrop to present the feasibility analysis. Comparing the power, time, control and motion planning complexities of eleven mission ConOps, the trade-off analysis shortlists a potential mission scenario. Furthermore, operational assessments of two potential mission ConOps are compared to estimate the time required for assembly. The study offers new insights into mission time requirements for these scenarios, shedding light on multi-robot collaborative task-sharing and practical applicability of the E-Walker in executing complex and high-value in-orbit assembly missions.