Thesis (MScEng)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: A multiprocessor hardware-in-the-Ioop operating system was developed for the Integrated Test System (ITS) and is aimed at implementing the ITS as a space emulation vehicle. The thesis contains a study of satellite orbits, Kepler elements, geomagnetic fields and communication protocol between the processors. The system structure consists of an orbit generator, a core-operating system and is presented with a study of the satellite sensors. In implementing the orbit propagator, there was a need to pay special attention to the Halving algorithm, the Newton Raphson method and the True Solution. These algorithms were used to calculate the true anomaly angle as a function of eccentric anomaly. The communications protocol was tested and all the errors, with their solutions, have been discussed. A concept of a geomagnetic field emulator has also been included in the hardware-in-theloop operating system. The evaluation of those aspects of the system and the conclusion are presented together with recommendations. / AFRIKAANSE OPSOMMING: 'n multiprosesseerder Hardeware in die lus bedryfstelsel is ontwikkel vir 'n Geintegreerde Toets Stelsel (ITS) en poog om die ITS te implementeer as 'n ruimte emulasie stelsel. Die tesis behels die studie van sateliet wentelbane, Kepler wentelbaan elemente, geomagnetiese velde en kommunikasie protokolle tussen die prosesseerders. Die stelsel struktuur betaal uit 'n wentelbaan propageerder, 'n kern bedryfstelsel en 'n studie van satelliet instrumentasie. As 'n deel van die implementering van die wentelbaan propageerder is die halveer algoritme, Newton-Raphson algoritme en die ware oplossing as numeriese oplossings ondersoek. Die kommunikasie protokol is getoets en foute ondersoek en word bespreek. 'n konsep vir 'n Geomagnetiese veld emulasie word die hardeware in die lus stelsel ingesluit. Die stelsel word ge-ewalueer en die gevolgtrekkings en aanbevelings gemaak.