Thesis (MEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: The next generation of CubeSats will require accurate attitude knowledge throughout
orbit for advanced science payloads and high gain antennas. A star tracker can
provide the required performance, but star trackers have traditionally been too large,
expensive and power hungry to be included on a CubeSat. The aim of this project
is to develop and demonstrate a CubeSat compatible star tracker. Subsystems from
two other CubeSat components, CubeSense and CubeComputer, were combined with
a sensitive, commercial image sensor and low-light lens to produce one of the smallest
star trackers in existence. Algorithms for star detection, matching and attitude determination
were investigated and implemented on the embedded system. The resultant
star tracker, named CubeStar, can operate fully autonomously, outputting attitude
estimates at a rate of 1 Hz. An engineering model was completed and demonstrated
an accuracy of better than 0.01 degrees during night sky tests. / AFRIKAANSE OPSOMMING: Die volgende generasie van CubeSats sal akkurate orientasie kennis vereis gedurende
'n volle omwentelling van die aarde. 'n Sterkamera kan die vereiste prestasie verskaf,
maar sterkameras is tradisioneel te groot, duur en krag intensief om ingesluit te word
aanboord 'n CubeSat. Die doel van hierdie projek is om 'n CubeSat sterkamera te ontwikkel
en te demonstreer. Substelsels van twee ander CubeSat komponente, CubeSense
en CubeComputer, was gekombineer met 'n sensitiewe kommersiële beeldsensor en 'n
lae-lig lens om een van die kleinste sterkameras op die mark te produseer. Algoritmes
vir die ster opsporing, identi kasie en orientasie bepaling is ondersoek en geïmplementeer
op die ingebedde stelsel. Die gevolglike sterkamera, genaamd CubeStar, kan ten
volle outonoom orientasie afskattings lewer teen 'n tempo van 1 Hz. 'n Ingenieursmodel
is voltooi en 'n akkuraatheid van beter as 0.01 grade is gedemonstreer.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/85746 |
| Date | 12 1900 |
| Creators | Erlank, Alexander Olaf |
| Contributors | Steyn, W. H., Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | xiii, 122 p. : ill. |
| Rights | Stellenbosch University |
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