The rapid development of space exploration and commercialisation places an increasing importance on semi-automated (or autonomous) space robotics for satellite servicing, extra-vehicular-activity (EVA) support, the construction of large space infrastructure (e.g. space stations, orbital solar power plants, space telescopes) and, not least, the active removal of the increasing amount of space debris present in Earth orbit.

To achieve these tasks in a cost-effective manner, full system autonomy is a requirement. However, at present, such systems are expensive to build and present numerous difficulties before they can be considered safe for launch. In orbit demonstrations of such technology have been carried out, but these have been limited in scope, and were designed with minimum fault tolerance. It is clear that significant effort will be needed to produce truly autonomous, adaptable, flexible and safe robotic systems to carry out such tasks routinely. To this end, ground based research is vital.

It has been found a 2-D (flat) air bearing table provides a practical, versatile and low-cost method of simulating the virtually friction free dynamics of spaceflight - albeit limited to a 2-D surface. Such a facility, when instrumented, will allow extensive periods of testing of robotic rendezvous and docking systems in a ground laboratory environment under controlled conditions. This allows for control algorithms to be tested and verified, dynamics to be analysed and rendezvous and construction techniques to be practiced before moving on to a full 3-D context such as a microgravity flight.

The system will be used to develop, test and evaluate rendezvous and docking control algorithms which make use of optical machine vision systems and inter-satellite communications for relative localisation and navigation, and which use an electro-magnetic docking system to provide the close-in (~30cm) approach manoeuvring and alignment and final docking/latching. The algorithms and electro-magnetic docking system will be practically tested and demonstrated using a 3U CubeSat type platform docking with a similar, passive, target vehicle.

To provide a suitable context, the requirements of the joint Surrey/CalTech "AAReST" Autonomous Assembly, Reconfigurable Space Telescope mission will be used to set the operational scenario.

Potential Impact:
The establishment of the Test-Bed within the Surrey Space Centre (SSC) will enable it to be available to the ~90 researchers and academics within the centre to use to further their research in astrodynamics, machine vision and navigation, space vehicle control, inter-satellite communications, distributed and on-board processing, and micro-thruster development.

The direct link between SSC and Surrey Satellite Technology Ltd (SSTL) gives a direct route to commercialisation of the IP generated.

Results from the project will be disseminated through conferences (e.g. 9th International Symposium of the IAA Small Satellites for Earth Observation, Berlin 2012 and AIAA Space 2012) and Journal publications, so that they may reach the wider academic community.

Direct Liaison with CalTech will ensure that the outcome of the research feeds into the AAReST project, which supports the joint academic activity between Surrey and CalTech in terms of research cooperation and student teaching, and also strengthens the relationship between NASA and the UKSA (NASA-JPL support the AAReST project and are looking to the UK to partner in the flight mission). UK industrial partners (Astrium-UK, SSTL) have already been approached and have expressed strong interest in the possibility of using AAReST as a test-bed for cross-platform software developments.

Autonomous robotic assembly is a key enabler for a lower cost approach to large space telescopes, but it also has much broader application and will be a breakthrough in the utilization of space. The economic potential for such applications is very significant and Surrey's work in this field is likely to accelerate progress significantly toward Governments objective of capturing 10% of the upstream and downstream satellite and services sector.

SSC hosts many school and college visits each year as part of its outreach activities, and the proposed test-bed is expected to become a key part of such visits as a demonstration of advanced space technology and engineering to visitors.