The University has eight faculties, two of which are involved in space propulsion: · the Faculty of Physical Sciences and Engineering, one of whose academic units is Electronics and Computer Science (ECS) incorporating the Electronics and Engineering Group with its Tony Davis High Voltage Lab, one of whose research groups is the Plasma and Space Science Group, with a strong interest in electric propulsion; and · the Faculty of Engineering and the Environment (FEE), which incorporates the Astronautics Group and which has interests in space systems engineering and both electric and chemical propulsion. The Plasma and Space Science and Astronautics Groups are therefore effectively independent organisations. This section concerns the Plasma and Space Science Group. In the field of electric propulsion, the Plasma and Space Science group has interests in: · gridded ion engines, collaborating closely with QinetiQ, Section 3.33 above; · PPTs (pulsed plasma thrusters), working with the University spin-off company Mars Space Ltd, Section 3.26 above; · HCTs (hollow cathode thrusters) being developed under ESA funding; · advanced 3-gridded ion engines (previously funded by an FP7 project, HiPER); and · heaterless hollow cathodes. The Plasma and Space Science group has a number of vacuum facilities for electric propulsion thruster testing, capable of producing the necessary high vacuum present in space. In addition, the group has two instruments used to evaluate PPT performance: a precision thrust balance to measure the impulse bit of pulsed thrusters and a sensitive mass balance which can be used to measure the mass bit. The Group’s research is focussed on two sizes of PPTs, one for CubeSats and the other for NanoSats. For the CubeSat PPT, research is being conducted on how to optimise performance whilst still achieving the long lifetimes needed (more than one million pulses) with particular emphasis on the spark plugs needed for the discharge initiation. The HCT being developed under ESA funding has applications for large communications satellites for east/west station-keeping and for attitude control, leading to the so-called all-electric spacecraft. A model capable of predicting thrust from first principles is being developed in order to optimise the design and meet a specific set of requirements in terms of power, thrust and specific impulse. An optimised thruster will be designed, manufactured and tested. In order to measure the thrust directly, a new thrust balance is being designed and built. Research on the fundamental aspects of hollow cathodes and HCTs has been ongoing for some 20 years and is internationally recognised.
The Plasma and Space Science Group has excellent facilities to support its in-house research interests and developments in electric propulsion. It is happy to collaborate with external users subject to availability of resources and normal commercial arrangements, as evidenced by its existing contracts with Mars Space, QinetiQ, ESA and the EU.
