IDRA: A Concept for an Inflatable and Retractable Robotic Arm for ISAM

This paper introduces a novel concept in space robotics: the Inflatable and Deployable Robotic Arm (IDRA). The IDRA differs from conventional robotic manipulators by incorporating inflatable links combined with rigid, electrically actuated joints. The link technology, provided with a mechanism for controlled deployment and retraction, aims to optimize volume efficiencies, critical for space missions. The inflatable links are designed with materials suitable for space environment. They are composed by three main layers: bladder layer for the containment of the fluid, restraint layer for the retention of the structural integrity and mechanical characteristics, protection layers, e.g., for thermal protection. The robot structure can be deployed to achieve a large operational workspace and retracted to minimize the system's footprint when not in use, enhancing safety and reducing vulnerability to space debris. The IDRA allows to apply traditional control strategies, e.g., visual servoing control to reach a target with high accuracy. Moreover, the integration of high-strength, lightweight materials and the implementation of advanced control strategies allow to achieve performances comparable to conventional robots, including precision in task execution. This system is versatile tool for a wide range of In-Space Servicing, Assembly, and Manufacturing (ISAM) tasks, including satellite maintenance, debris removal, and the assembly of large structures in orbit. The system's adaptability and reduced stowed volume allow for its application in supporting astronautical activities in space stations. Finally, its integration onto autonomous rovers could enable further tasks to lunar and Martian terrains.