HONOURS SCHOLARSHIPS
The current AAO vision for controlling the positioning of the payloads uses a fixed camera imaging the focal plane, with software locating the Starbugs providing feedback for motion control. This solution suffers from various limitations, such as an inability to sense position while observations are in progress, due to light contamination. This project aims to research and test other position feedback systems - perhaps microwave sensing systems, interpolated grids, or others.
For the new 'AAOmega' fibre system proposed for the AAT - a significant upgrade
to 2dF - there are additional constraints on the fibre allocation, and the
existing algorithm needs to be reworked. An interesting possibility is to
use the increased computing power now available to apply some of the
more computationally-intensive algorithms such as 'simulated
annealing'. Applying this to the AAOmega system presents a number of
challenges. The existing allocation program runs interactively, allowing
an observer to modify the results of the current algorithm. We suspect that an
annealing algorithm will not quite be fast enough to be attractive as an
interactive option, but we hope that it can be run in batch mode and will
produce results that do not need to be massaged interactively!
We hope that if this works well it can be applied to other fibre
positioning systems as well. This is a project that would suit someone who
combines C programming expertise with an interest in algorithm development,
and who would enjoy producing something that will be used for some major
astronomical surveys.
More details can be obtained from Keith Shortridge (ks)
For details on 2dF, see http://www.aao.gov.au/2df
Simulated annealing is a well-known algorithm. See for example, http://www.cs.sandia.gov/opt/survey/sa.html
As part of the design studies for FASTCAM we are carrying out test observations of stars and planets with a high speed video camera to investigate the performance of selective imaging techniques as a function of parameters such as exposure time and telescope aperture. The project will involve analysing these observations and using the results to contribute to the design of FASTCAM and the development of its data reduction software.
With the development of Photonic Crystal Fibres (PCFs), fibre sensor technology has been given a significant boost. These take advantage of various non-linear properties of PCFs. Since multiple gratings can be imprinted almost anywhere along the fibre length, the use of different grating periods and a wavelength-scanning technique can be used to monitor position, strain/flexure and temperature (for example) at a number of interconnected locations using the same fibre, source and detector. With PCFs it is relatively easy to introduce non-linear effects that can be used for monitoring and sensing systems. For example, a system can be designed that utilises the polarisation-preserving properties of asymmetric waveguides, where the level of external stress determine the level of polarisation isolation in the fibre or the bend loss edge in single mode fibres that is sensitive to bending and stresses. With multiplexing, a number of sensor fibres could be monitored with the same system, providing a robust, remote, highly multiplexed and EM-tolerant sensing system with many applications. These include monitoring the structure/flexure in extremely large telescopes (ELTs) and their instrumentation, active monitoring of the condition of fibre bundles, feedback system for actuators and anywhere in such systems where such monitoring/sensing is required. With radiation-hard fibres there are obvious gains for space application or other radiation-hash environments with numerous potential applications.
The project would carry out a review of current fibre sensor technologies, identifying those that offer significant advantages for Astronomy applications over more conventional sensing systems and then test and prototype a demonstration system. An area that is of particular interest to the WFMOS design (A very large wide feild spectroscopic system for the Gemini 8-metre telescopes) is in the active monitoring of the optical fibre bundles from the telescope top end to the remote mounted spectrographs. This is because stressing of the fibre can significantly impact system performance and, in the extreme case, could cause damage to the optical fibre bundle terminals.
For further details can be obtained from
For further details, application forms etc click
HERE and
follow the links the scholarship page.
Prospective honours scholarship applicants should apply in writing to:
Dr. Q.A.Parker
Honours Scholarship Program
Macquarie University
Department of Physics
Epping, NSW 2120
AUSTRALIA
The closing
date for applicants:
11 October 2004