Demonstration shows viability of spacecraft assembly in orbit
When one thinks about how satellites and spacecraft are currently built, the picture that usually springs to mind is of a huge clean room with lots of white-coated scientists and experts milling around. After being meticulously constructed, these expensive pieces of equipment then need to be launched into space. This work is incredibly costly, as well as highly labour-intensive. This is one reason why the EU-funded PERIOD project was launched, to see if an alternative to current approaches to manufacturing and assembling space hardware on the ground could be found.
Robotics and automation in space
In particular, the project sought to examine in-depth the possibility of direct in-orbit manufacturing and assembly, using robotics and automation. “The advantages of this would be multiple,” explains PERIOD project coordinator Stéphane Estable from Airbus Defence and Space in Germany. “These include no more constraints on the overall volume and design of large-scale satellite antennae, and opportunities to construct larger space infrastructures, such as modular space stations.” On top of this, robotic-based in-space manufacturing and assembly technologies could allow for the upgrade and repair of existing spacecraft and satellites. A key barrier to date, however, has been an inability to demonstrate the maturity and integrability of such technology. In other words, could it actually work?
Validating in-orbit manufacturing
The main motivation for PERIOD therefore was to further develop and validate promising in-space service technologies. These innovations – such as a robot operating control system, a sensor data fusion framework, an autonomy goal-oriented framework and an integrated 3D sensors suite – were developed in the framework of the EU’s PERASPERA Strategic Research Cluster. The project team also tested and benchmarked ‘standard interconnects’, which would enable modular robotic systems to be combined. “To achieve this, a lab demonstrator was prepared, which gradually integrated all these technologies together in increments with increasing complexity,” adds Estable. “We were also able to carry out a robotised assembly sequence of a satellite mock-up, made of two main segments both equipped with a ‘standard interconnect’.” This work enabled the team to define in detail how robotic technologies could be used together for antenna manufacturing, satellite assembly and satellite refuelling, in orbit.
Advancing cutting-edge technologies
PERIOD was successful in further developing and validating these technologies, and in carrying out a highly detailed benchmarking of three European standard interconnects. In doing so, the project team was able to demonstrate, in the lab, how a robotic-based satellite assembly operation could be carried out, in space. The project also contributed to defining the standards and regulations for in-space services, manufacturing and assembly, which will be important in moving forward. More focused work on this is envisaged in the future. Critically, many of the project outcomes are now available for future activities within the space community. “The lab demonstrations – and in-orbit demonstration concept we developed – will also enable the space community to build the business case for how space systems are designed and operated in the future,” says Estable. “We will continue developing these technologies, and also continue to carry out lab demonstrations of in-space services with increasing complexity. Our aim is to eventually implement an in-orbit demonstration to fully validate the overall operations and technologies, before the deployment of commercial applications.”
Keywords
PERIOD, space, satellite, spacecraft, robotic, PERASPERA, in-orbit