Lead Organisation: Surrey Space Centre, University of Surrey (SSC)
Project Lead: Aglietti Guglielmo
Partners: Surrey Satellite Technology Limited (SSTL)
The ever-increasing demand for high resolution imagery for the Earth observation market, with latency of minutes rather than days, requires satellite constellations, and due to the limited capabilities of current launch vehicles there is a need to reduce significantly the size and cost of the payload/camera and satellites.
However, to maintain the required resolution, the size of the optics and distance between elements cannot be significantly reduced. Therefore there is a need for deployable systems where the structure that supports the optical elements can be folded to allow a tightly packed configuration during launch and then deployed once in space, to position the optical elements at the required distances.
The objective of this project is to develop a physical proof of concept of a deployable optical system to pave the way to its implementation in a real SSTL demonstration mission. This mainly utilized as building blocks technologies that are known, with the main innovation at system level, bringing together all the elements, with the necessary modifications to realize a system that meets the end-to-end requirements, thus de-risking its use in real missions to a level compatible with SSTL business model. Note that to date, the types of deployable system envisaged in this project have haven’t yet reached a level of maturity to allow them to fly.
Initially several designs were proposed and through a trade-off analysis and the input of the technical customer, SSTL, the chosen design to take forward was a deployable tube concept. The detailed design focussed on the deployment screws and the lock out of the tubes to ensure stiffness and stability of the tubes to meet the deployment accuracy and vibration requirements.
Two prototypes were built. A breadboard built using 3D printed parts was first assembled to demonstrate the concept. A second prototype was built using CFRP tubes to represent a more ‘flight ready’ set-up. The prototype was successfully tested to check that it met the requirements for deployment accuracy, vibration and thermal elastic behaviour.
The project was successfully delivered with a slight over-run on the schedule due to a higher level prototype being developed. A follow-on project, lead by SSTL, has been awarded to take the current design and create a flight model.