Smart optics for satellite instrumentation
PI: Martin Booth
Department: Engineering Science
A significant challenge for optical earth observation systems is the alignment of the telescope components. Systems are frequently out of alignment, at least in part, leading to unfocussed or incomplete images, a major cause of failure of satellite missions. This feasibility project will focus upon the alignment of the optics within a factory build context, as the first step towards the longer term goal, which includes the ability to robotically adjust telescopes in orbit and develop self-correction systems using appropriate actuators.
The long-term aim of our work is to develop adaptive optic techniques for application to telescopes, building upon world-leading expertise at the University of Oxford on adaptive systems for microscopes and related applications and world-leading satellite development and deployment expertise at Surrey Satellite Technology Ltd. This project will also be in collaboration with the Satellite Applications Catapult, which is establishing a Disruptive Innovation for Space Centre (DISC) to be located in Oxfordshire, with one of its focus areas on the automation of satellite manufacturing and operational systems. This will be a potential route for the scale-up and industrialisation of what is developed through the IAA award.
The current industrial approach to aligning satellite optics is manual, with adjustments informed by measurements from camera images of alignment laser beams and from live interferometry; heuristic and time-consuming techniques. We will bring automation into the alignment process by adopting methods for adaptive optics using indirect measurements to infer the aberrations in the system such as, in this case, the misalignment of mirrors and other components. This modified procedure has demonstrated a substantial improvement in comparison to traditional wavefront sensors in microscope devices. Existing methods are inefficient and inexact and therefore require a very large number of iterative steps. The new methods will dramatically reduce these from about nine person-months to potentially one person-month. Combining the approach with other techniques such as interferometry, greater sensitivities may be achieved by using interferograms for finer tuning.
A successful feasibility study will lead on to full scale demonstration associated with a real satellite mission undertaken by SSTL and further development phases towards automated in-orbit demonstration with associated IPR and business model development