Multi-Functional Interface for Flexibility and Reconfigurability of Future European Space Robotic Systems

Abstract

The capabilities of maximising standard payload modules’ functionalities for applications such as on-orbit satellite servicing or planetary exploration depend critically on the creation and availability of a standard interface (IF). Standard interface should provide, aside from the necessary mechanical interconnections, electrical power and data connections, as well as thermal transfer between “building block” payload modules. The overall flexibility enabled by such IF will allow endless reconfigurations of payload and other modules for different functional requirements. This can be considered a game changer technology, enabling transformation from the current approach to space missions, deploying single-use system with pre-planned and limited functionalities, to a radically new approach with multi-use, dynamically reconfigurable and multi-functional systems. Hence, SIROM aims to set a new research agenda for future affordable space missions. Within this context, the partners of the SIROM (Standard Interface for Robotic Manipulation of payloads in future space missions) project are developing the first standard IF solution that combines the four required functionalities in an integrated and compact form for future space missions. With a mass lower than 1.5 kg and having an external diameter of 120 mm and a height of 30 mm, this novel interface permits not only mechanical coupling but also electrical, data and thermal connectivity between so called Active Payload Modules (APMs), as well as other modules such as the robotic end-effectors. This multi-functional IF features an androgynous design to allow for replacement and reconfiguration of the individual modules in any combination desired. It consists of the following sub-assemblies: mechanical IF, electrical IF, data IF, thermal IF and IF controller. A clear advantage of SIROM design is that its mechanical IF consists of a latching and guiding systems for misalignment correction, capable of withstanding certain robotic arm positioning inaccuracies: ± 5 mm translation and ± 1.5° rotation in all axes. Regarding the electrical and data IFs, SIROM transfers up to 150 W electrical power and provides a data transfer rate of 100 Mbit/s via SpaceWire, plus command communication with speeds up to 1Mbit/s via CAN bus. The thermal IF provides fluidic ports for flow transfer and has the potential to transfer 2500 W between APMs accordingly provided with the corresponding close-loop heat exchange system. Although not envisaged for SIROM current design, a possible variation could be to use these ports for satellite re-fuelling. Apart from that, SIROM exhibits redundant coupling capabilities: it can match and couple another completely passive SIROM. It is provided with main and redundant connectors for thermal, electrical, data and control flow in case of one of the lines fails. All in all, SIROM will enable long duration missions with no logistic support, refurbishing, maintenance and reconfiguration of satellites, cost efficiency and simplification of the tool exchange in scientific exploration missions. SIROM is designed to be a common building block for European and possibly world future space robotics enabled missions.