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The extensive use of virtual prototyping methods has become an indispensable tool in the context of Model-Based Design of complex space missions. Modelling the behaviour of such missions often requires considering systems that are composed of physical subsystems (usually from different physical domains) together with computing and networking. Perpetual Labs is developing a new software platform for collaborative design of CPS called Cloud System Factory (CloudSF). It enables all the stakeholders of a complex engineering system to exchange system data and engineering artefacts independently of the specific tools that they are using. The proposed benefits of the CloudSF platform will be demonstrated and measured through the application of said platform to the model-based design and verification of a robotic system for on-orbit assembly of telescopic structures using an End-Over-End Walking robot, called the E-Walker.

Modular Large Aperture Space Telescopes (LAST) hold the key to future astronomical missions in search of the origin of the cosmos. Robotics and Autonomous Systems technology would be required to meet the challenges associated with the assembly of such high value infrastructure in orbit. In this paper an End-Over-End walking robot is selected to assemble a 25m LAST. The dynamical model, control architecture and gait pattern of the E-Walker are discussed. The key mission requirements are stated along with the strategies for scheduling the assembly process. A mission concept of operations (ConOps) is proposed for assembling the 25m LAST. Simulation results show the precise trajectory tracking of the EWalker for the chosen mission scenario.

MBSE aims to integrate engineering models across tools and domain boundaries to support traditional systems engineering activities (e.g., requirements elicitation and traceability, design, analysis, verification and validation). However, MBSE does not inherently solve interoperability with the multiple model-based infrastructures involved in a complex systems engineering project. The challenge is to implement digital continuity in the three dimensions of systems engineering: across disciplines, throughout the lifecycle, and along the supply chain. Space systems are ideal candidates for the application of MBSE and semantic modelling as these complex and expensive systems are mission-critical and often co-developed by multiple stakeholders. In this paper, the authors introduce the concept of Semantic Systems Engineering (SES) as an expansion of MBSE practices to include semantic modelling through SWTs. The paper also presents the progress and status of a novel Semantic Systems Engineering Ontology (SESO) in the context of a specific design case study – the Large Aperture Space Telescope mission.

With the advances in Robotics, Automation and Autonomous Systems (RAAS), the horizon of space exploration has grown, and there is a need to develop space-qualified intelligent robots for future missions. Building upon the heritage of successful surface exploration rover and lander missions to the Moon, Mars and Asteroids, the space community worldwide is now pushing the frontiers of in-orbit robotics. Doubtlessly, RAAS will facilitate a range of manufacturing, assembly, servicing and active debris removal missions. Resources published by space agencies and major companies worldwide clearly indicate that mankind will start witnessing in-orbit robotic missions within the next decade. This includes but not limited to building modular Large-Aperture Space Telescopes (LAST), synthetic aperture radar, radiofrequency antennas, in-space power generation stations, mobile servicing stations for repairing and maintenance of satellites and possibly large-scale infrastructure for space tourism. Out of the many potential missions RAAS could support, in-orbit robotic assembly and construction of LAST is gaining more popularity with the intent to understand the rate of growth of the cosmos and also for Earth Observation (EO). However, there are numerous technical challenges associated with assembling LAST in space, including its manufacturing and stowing into current and planned launch vehicles. To address these issues, a segmented design approach for LAST is considered in this paper; the modular mirror units will be robotically assembled in orbit. The in-space assembly of a modular 25m LAST mission concept is presented using a five Degrees-of-Freedom End- Over-End Walking Robot (E-Walker). The design and gait pattern of the E-Walker is introduced first. The key mission requirements including the requirements for the Robotic System, Space Telescope and Assembly are discussed along with the strategies for scheduling the assembly process. Four main mission scenarios, subcategorised i

Over the last few decades, Space robots have found their applications in various in-orbit operations. The Canadarm2 and the European Robotic Arm (ERA), onboard the International Space Station (ISS), are exceptional examples of supervised robotic manipulators (RMs) used for station assembly and mainte­nance. However, in the case of in-space assembly of structures, like Large-Aperture Space Telescope (LAT) with an aperture larger than the Hubble Space Telescope (HST) and James Webb Space Telescope (JWST), missions are still in their infancy; this is heavily attributed to the limitations of current state-of-the-art Robotics, Automation and Autonomous Systems (RAAS) for the extreme space environ­ment. To address this challenge, this paper introduces the modelling and control of a candidate robotic architecture, inspired by Canadarm2 and ERA, for in-situ assembly of LAT. The kinematic and dynamic models of a five degrees-of-freedom (DoF) End-Over-End Walking robot's (E-Walker's) first phase of motion is pre­sented. A closed-loop feedback system validates the system's accurate gait pat­tern. The simulation results presented show that a Proportional-Integral-Derivative (PID) controller is able to track the desired joint angles without exceeding the joint torque limits; this ensures precise motion along the desired trajectory for one full cycle comprising of Phase-1 and Phase-2 respectively. The gait pattern of the E-Walker for the next phases is also briefly discussed.

Space has found itself amidst numerous missions benefitting the life on Earth and for mankind to explore further. The space community has been in the move of launching various on-orbit missions, tackling the extremities of the space environment, with the use of robots, for performing tasks like assembly, maintenance, repairs, etc. The urge to explore further in the universe for scientific benefits has found the rise of modular Large-Space Telescopes (LASTs). With respect to the challenges of the in-space assembly of LAST, a five Degrees-of Freedom (DoF) End-Over-End Walking Robot (E-Walker) is presented in this paper. The Dynamical Model and Gait Pattern of the E-Walker is discussed with reference to the different phases of its motion. For the initial verification of the E-Walker model, a PID controller was used to make the E-Walker follow the desired trajectory. A mission concept discussing a potential strategy of assembling a 25m LAST with 342 Primary Mirror Units (PMUs) is briefly discussed. Simulation results show the precise tracking of the E-Walker along a desired trajectory is achieved without exceeding the joint torques.