Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: The focus of this thesis is on South Africa's first micro space satellite SUNSAT, and the thermal modelling thereof. Background theory with relevance to thermal management and control of satellite systems and subsystems is presented. The mission profile and subsystem makeup of SUNSAT is also briefly discussed, with emphasis placed on the physical structure, possible orbit paths, internal heat generation, and the environmental heating. The environmental heating on the satellite surfaces from the direct and reflected earth solar radiation, as well as the earth emitted infrared radiation, is determined from the developed computer program ORBIT-FLUX. This program was used in tandem with numerical programs (developed in house), as well as an outsourced program TAS (Thermal Analysis Systems) to model SUNSAT for two possible orbit paths. The resistance-capacitance formulation method was used to develop the numerical programs, which served initially to establish the validity ofTAS. The first approximated thermal model of SUNSA T's batteries was the 7 lumped-mass model that focused on the batteries since their overheating is the suspected reason for SUNSA T'S failure to complete its mission. A numerical program as well as a similar TAS model was developed, and the results showed correlation to within 3°C. A lumped-mass model of SUNSAT was also developed, both numerically and using TAS. The models were tested and the results showed that the temperatures of the models were sensitive to changes in internal heating as well as varying emissivity and absorptivity. The numerical and TAS lumped-mass model results did not correlate well, possibly due to the higher number of control volumes used in the TAS lumped-mass model. The TAS SUNSAT 2 model was developed as advancement on the lumped-mass model. The higher number of control volumes and the effect of adding solar panels gave a more realistic model of SUNSA T. The results did not show good correlation with actual SUNSA T temperature data possibly due to the fact that the solar panels were not mounted on the model body as they were on SUNSA T; but the TAS SUNSA T 2 model did set the platform for the more advanced TAS SUNSAT 3 model. This thermal model included the effects of the solar panel mountings, and had a higher number of control volumes, which gave a better physical representation of the SUNSAT subsystems. The model was tested for possible orbit paths of SUNSA T. The results showed excellent correlation to actual SUNSA T data. For the comparison of the TAS SUNSA T 3 model results with data from SUNSAT for July 1999 showed that the SUNSA T battery temperature was modelled to within 8°C. And for June 2000, this same comparison was to within 1°C. A thermal management and control case study was done on a simple system (which included a cubic box and an internal solid block with heat generation) to illustrate the effects of using various passive and active thermal control hardware to regulate temperatures. The results showed that internal surfaces painted black provide for maximum heat sharing, and lowest block temperatures. The block temperatures were found to be very sensitive to changes in the cube external optical surface properties. A slight increase in emissivity lowered the block temperature, while a slight increase in absorptivity increased the block temperature. Heat pipes were also found to lower the temperatures of the block and immediate subsystems by providing a path of low thermal resistance to the flow of heat from the block directly to the radiator. The effect of thermal insulation was also investigated. For the two materials (rubber and plastic) that were tested, it was noticed that although insulation material does give more thermal control and predictability over a subsystem by thermally isolating it from its environment, it can cause a subsystem that has heat generation to become too hot. Recommendations were made relating to future micro satellite thermal management and control with regard to; thermal modelling techniques, acquisition of tried software, positioning of temperature sensors for optimisation of thermal data, and the verification of optical surface properties by physical measurement. / AFRIKAANSE OPSOMMING: Hierdie tesis fokus op Suid-Afrika se eerste mikro ruimte satelliet, SUNSAT, en die termiese ontwikkeling daarvan. Agtergrond teorie met betrekking tot die termiese bestuur en kontrole van die satelliet-sisteme en subsisteme word aangebied. Die missie-profiel en die samestelling van die subsisteme word ook kortliks bespreek met die klem op die fisiese strukture, moontlike wentelbane, interne hitte-opwekking, en die omgewingsverhitting. Die omgewingsverhitting op die oppervlaktes van die satelliet, veroorsaak deur direkte en weerkaatste aardlson bestraling, sowel as deur infrarooi bestraling afkomstig van die aarde, word bepaal deur die ontwikkelde rekenaarprogram ORBIT-FLUX. Hierdie program word gebruik in tandem met numeriese programme (intern ontwikkel), so weI as 'n uitgekontrakteerde program TAS (Termiese Analiese Sisteme) om SUNS AT vir twee moontlike wentelbane te modelleer. Die weerstandskapasitansie formuleringsmetode is gebruik om die numeriese programme te ontwikkel. Hierdie programme is oorspronklik gebruik om die validiteit van TAS vas te stel. Die eerste benaderde termiese model van SUNSAT se batterye was die 7 gekonsentreerdemassa model wat gefokus het op die batterye aangesien daar vermoed is dat oorverhitting van die batterye die rede is waarom SUNSAT nie sy missie voltooi het nie. 'n Numeriese program so weI as 'n gelyksoortige TAS model is ontwikkel en die resultate korreleer tot binne 3°C. 'n Gekonsentreerde-massa model van SUNSA T is ook ontwikkel, numeries en met gebruik van TAS. Die modelle is getoets en die resultate toon dat die temperature van die modelle gevoelig is vir veranderinge in interne hitte sowel as vir wissellende uitstralingsvermoe en absorpsievermoe, Die numeriese- en die TAS gekonsentreerde-massa model resultate het nie goed met mekaar korrelleer nie, moontlik weens die hoe aantal kontrole volumes wat in die TAS gekonsentreerde-massa model gebruik is. Die TAS SUNSA T 2 model is 'n verdere ontwikkeling van die gekonsentreerde-massa model. Die hoer aantal kontrole volumes en die byvoeging van solarpanele het tot gevolg gehad dat hierdie 'n meer realistiese model van SUNSA T is. Die resultate het nie goed gekorrelleer met die temperatuurdata van die werklike SUNSAT nie, moontlik weens die feit dat die solarpanele nie op die bakwerk monteer is, soos in die geval van SUNSA T nie. Nietemin het het die TAS SUNSAT 2 model gelei tot die meer gevorderde TAS SUNSAT 3 model. Hierdie termiese model het die solarpaneel montuur ingesluit en het 'n hoer aantal kontrole volumes gehad, wat 'n beter fisiese weergawe van die SUNSAT subsisteme tot gevolg gehad het. Die model is getoets vir moontlike wentelbane van SUNSAT. Die resultate het 'n hoe korrellasie getoon met die data van die werklike SUNSAT. 'n Vergelyking van die TAS SUNSAT 3 model resultate met data van SUNSAT vir Julie 1999 wys dat die SUNSAT battery temperatuur dieselfde is tot binne 8°C. Vergelyk met die resultate vir Junie 2000 was dit binne 1°C. 'n Termiese bestuurs- en kontrolestudie is gedoen op 'n eenvoudige sisteem (insluitende 'n kubieke boks en 'n interne soliede blok met hitte opwekking) om die uitwerking van die gebruik van passiewe en aktiewe termiese kontrole hardeware wat temperature reguleer, te illustreer. Die resultate toon dat interne oppervlaktes wat swart geverf is, lei tot die maksimum hitte-deling, en die laagste bloktemperature. Daar is gevind dat bloktemperature baie gevoelig is vir veranderinge in die eienskappe van die kubus se eksterne optiese oppervlaktes. 'n Effense vermedering van uitstralingsvermoe verlaag die bloktemperatuur, terwyl 'n effense vermedering van absorpsievermoe die bloktemperatuur verhoog. Daar is ook gevind dat hittepype die temperatuur van die blok en onmiddelike subsisteme verlaag deur om 'n pad van lae termiese weerstand teen die vloei van hitte vanaf die blok, direk na die verkoeler te verskaf. Die uitwerking van termiese isolasie is ook ondersoek. In die geval van die twee materiale (rubber en plastiek) wat getoets is, is daar opgemerk dat, alhoewel isolasie materiaal meer termiese beheer oor die subsisteem en voorspelbaarheid tot gevolg gehad het deurdat die subsisteem termies van die omgewing isoleer is, kan dit veroorsaak dat die subsisteem te warm word. Aanbevelings is gemaak met betrekking tot toekomstige mikro satelliet bestuur en kontrole en wel in verband met die volgende: termiese modelleringstegnieke, die aanskaffing van getoetste sagteware, die plasing van temperatuut sensors vir die beste termiese data, en die verifikasie van die eienskappe van optiese oppervlaktes deur fisiese meting.

Thesis (MEng (Electrical and Electronic Engineering))--University of Stellenbosch, 1995. / 189 leaves single sided printed, preliminary pages and numbered pages 1-126. Includes bibliography, list of appendixes, figures, notation and symbols. Digitized at 300 dpi (OCR), using a Bizhub 250 Scanner. / ENGLISH ABSTRACT: The Sunsat microsatellite is being developed at the University of Stellenbosch. It is equipped with a high resolution earth imager which requires a sophisticated attitude determination and control system. Precise control of the satellite is impossible without high precision attitude sensors. The most accurate attitude sensor presently used by satellites is the star sensor. The aim 'of this thesis is to develop a low cost, high precision star sensor for the Sunsat microsatellite. The development included the selection of electronic and optical hardware followed by the design, construction and testing of the sensor. Software algorithms were developed and programmed to control the imager, extract stars from images and match the observed constellations to a star catalogue. A set of matching observed and reference vectors are passed to the attitude determination and control system which calculates the three axis orientation of the satellite. / AFRIKAANSE OPSOMMING: Die Sunsat mikrosatelliet word tans by die Universiteit van Stellenbosch ontwikkel. Dit is toegerus met 'n hoeresolusie aardwaarnemingskamera en vereis 'n gevorderde orientasiebepaling-en beheerstelsel. Presiese beheer is onmoontlik sonder akkurate sensore. 'n Stersensor is die mees akkurate tipe sensor waarmee satelliete tans toegerus word. Die doelwit van hierdie tesis is die ontwikkeling van 'n hoe resolusie, laekoste stersensor vir die Sunsat mikrosatelliet. Die ontwikkeling behels die seleksie van elektroniese en optiese apparatuur wat gevolg is deur die ontwerp, opbou en toets van die sensor. Programmatuur algoritrnes is ontwerp om die kamera te beheer, sterre in fotos te herken en waargenome konstellasies in die sterkatalogus te vind. 'n Stel waargenome en verwysingsvektore stel die orientasiebepaling-en beheerstelsel in staat om die orientasie van die satelliet te bereken.

Dissertation (Ph. D.)--University of Stellenbosch, 1997. / Bibliography. Also available via the Internet

Thesis (MScEng)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: The aim of this thesis is to investigate a design of a microcontroller based embedded system that will be used to minimise cable harness on the SUNSAT micro-satellite. The system is called CAN node. The CAN node(s) implements CAN (Controller Area Network) serial bus architecture protocol. The protocol is implemented on the two nodes to transport data from the TCMD tot he 0 ther trays 0 f SUNSAT. CAN node( s) design proj ect focuses on the TCMD tray, because it is the central point for data communication in SUNSAT and it acts as the eyes and hands of the satellite's operator. As a result most of the communication cables are located at this tray. The two nodes are called TX-node and RX-nodes. The TX-node is used to collect data from the TCMD tray and transmits them serially to RX-node. The RX-nodes receives the TCMD data from TX-node and transmits these data to their respective nodes. In application RX-nodes need to be ten, but only one is used for testing purpose. The design had its shortcomings, of which they are discussed in this thesis. The recommendations of an ideal system are also given to elaborate how the system should behave in the real situation. Despite its shortcomings, the CAN node(s) project has successfully proven that cable harness on the TCMD tray of SUNSAT can be minimised by using CAN technology. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis is om die ontwerp van 'n mikro-beheerder gebaseerde stelsel wat die SUNSA T mikro-satelliet kabel harnas sal verklein, te ondersoek. Die stelsel word die CAN nodus genoem. Die CAN nodus implementeer die CAN (Controller Area Network) bus argitektuur protokol. Die protokol is op twee nodusse geïmplementeer om data vanaf die TCMD na ander laaie van SUNSAT te voer. Die CAN nodus ontwerp fokus op die TCMD laai, want dit is die sentrale punt vir data kommunikasie in SUNSA T en dit tree soos die oog en hande van die satelliet operateur op. As 'n gevolg, is die meeste van die kommunikasie kabels in hierdie laai. Die twee nodusse is genoem TXnodus en RX-nodus. TX-nodus word gebruik om die data van die TCMD af te kollekteer en dan versprei hulle tot hulle onderskeie nodusse. In die toepaslik moet daar tien RX-nodusse wees, maar net een is gebruik terwille van die toets. Die ontwerp het sy eie tekortkomings, wat in hierdie tesis bespreek word. Die rekommendasie van 'n ideale stelsel is ook gemaak om te bewys hoe die stelsel dit in 'n ware situasie moet gedra. Ongeag die tekortkomings daarvan, het die CAN-nodus projek suksesvol bewys dat die kabel harnas in die TCMD laai van SUNSAT kan verminder word deur die gebruik van die CAN tegnologie.

Thesis (MScEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The aim of the thesis is the design of an economical do - it - yourself ground station for school pupils to communicate with SUNSAT 1. The ground station should also be more economical than a hand - held transceiver radio. The do - it - yourself requirement is there to arouse an interest in electronics, radio frequency electronics and satellite communications in school pupils. A system-level design was done for a ground station consisting of modules which may be bought individually as do - it - yourself kits to eventually produce a full set. The modules are a VHF receiver, a VHF transmitter, a UHF down converter and a modem. Each module has functions which aid in the process of communications (data as well as voice) between the satellite and the ground station. A VHF receiver was designed and implemented to be capable of receiving RF signals from SUNSAT 1. A crystal controlled oscillator was designed that oscillates with a frequency tolerance of less than or equal to ± 0.003 % when aligned without the necessary IlF equipment. An economical Broadband Signal Generator was implemented with a 74ACT14 logic IC, which may be used to align the receiver. The higher harmonics of a square wave with a fundamental frequency of 4 kHz are used as a RF source. A sound card was utilised as a modem to receive 1200 baud AFSK (AX.25 protocol) data and the software was also used to display the data on PC. The data was transmitted from another ground station / AFRIKAANSE OPSOMMING: Die doel van die tesis is die ontwerp van 'n ekonomiese doen - dit - self - grondstasie vir skoolkinders om met SUNSAT I te kan komunikeer. Die grondstasie moet ook meer ekonomies wees as 'n handstelradio. Die doel van die doen - dit - self - beginsel is om die belangstelling in elektronika, RF elektronika and satelliete by skoolkinders aan te moedig. 'n Stelsel ontwerp van 'n grondstasie is gedoen wat bestaan uit modules wat afsonderlik as doen - dit - self - modules aangeskaf kan word om so tot 'n totale grondstasie op te bou. Die modules is die "VHF" - ontvanger, "VHF" - sender, UHF - afmenger en 'n modem. Elke module verskaf funksies wat bydra om met SUNSAT I te kan kornmunikeer. 'n VHF - ontvanger wat in staat is om RF - seine vanaf SUNSAT I te ontvang is ontwerp en gebou. 'n Kristal b heerde ossillator is ontwerp met 'n frekwensie toleransie van kleiner en gelyk aan ± 0.003 % wanneer dit ingestem word sender die nodige RF toerusting. 'n Ekonomiese wyeband - seingenerator is gemplementeer met 'n 74ACT14 logiese vlokkie om as 'n RF - bron gebruik te word om die ontvanger in te stel. Die boonste (hoer) harmoniek van die 4 kHz vierkantsgolf word as 'n "RF bron" gebruik. 'n Klankkaart is suksesvol gebruik as 'n modem om 1200 baud AFSK data (AX.25 protokol) te ontvang en die data met die nodige sagteware op 'n skerm te vertoon. Data is uitgcstuur vanaf 'n ander grondstasie.

Thesis (MEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: This thesis describes the development of a distributed ground support system to be used in the small satellite program at the University of Stellenbosch. A literature study was done to determine the current trends in ground support design. These trends are presented together with an analysis of the SUNSAT groundstation software. New technologies in the field of distributed systems are discussed and used in the design of a distributed ground support system. The design centres around a servicesbased architecture where services are distributed on the network. The design is evaluated according to attributes exhibited by effective distributed systems. Certain services were implemented to demonstrate the feasibility of the design. The implementations are discussed and suggestions are made for future improvements and fields of possible further study. / AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die ontwikkeling van 'n verspreide-grondstasie-sisteem vir gebruik in die Universiteit van Stellenbosch se satelliet-program. Eerstens is 'n literatuurstudie gedoen om die huidige verwikkelinge in die veld van satellietondersteuning-ontwikkeling vas te stel. Hierdie verwikkelinge word bespreek en gebruik om die SUNSAT-grondstasie sagteware te evalueer. Nuwe tegnologieë in die veld van verspreide stelsels word ondersoek en bespreek. Die ontwerp van die grondstasie is gebaseer op 'n verspreide dienste argitektuur. Die ontwerp word beskryf en geëvalueer aan die hand van kenmerke tipies van 'n effektiewe verspreide stelsel. Om die werkbaarheid van die ontwerp te toon, is sekere van die dienste geïmplimenteer, en die funksionering daarvan word bespreek. Voorstelle word ook gemaak oor moontlike toekomstige navorsing wat gedoen kan word.

Thesis (MScEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: One of the problems with any deep space communication system is that information may be altered or lost during transmission due to channel noise. It is known that any damage to the bit stream may lead to objectionable visual quality distortion of images at the decoder. The purpose of this thesis is to design an error correction and data compression algorithm for image protection, which will allow the communication bandwidth to be better utilized. The work focuses on Sunsat (Stellenbosch Satellite) images as test images. Investigations were done on the JPEG 2000 compression algorithm's robustness to random errors, putting more emphasis on how much of the image is degraded after compression. Implementation of both the error control coding and data compression strategy is then applied to a set of test images. The FEe algorithm combats some if not all of the simulated random errors introduced by the channel. The results illustrates that the error correction of random errors is achieved by a factor of 100 times (xl00) on all test images and that the probability of error of 10-2in the channel (10-4for image data) shows that the errors causes little degradation on the image quality. / AFRIKAANSE OPSOMMING: Een van die probleme met kommunikasie in die ruimte is dat informasie mag verlore gaan en! of gekorrupteer word deur ruis gedurende versending deur die kanaal. Dit is bekend dat enige skade aan die bisstroom mag lei tot hinderlike vervorming van die beelde wat op aarde ontvang word. Die doel van hierdie tesis om foutkorreksie en datakompressie te ontwikkel wat die satelliet beelde sal beskerm gedurende versending en die kommunikasie kanaal se bandwydte beter sal benut. Die werk fokus op SUNSAT (Stellenbosch Universiteit Satelliet) se beelde as toetsbeelde. Ondersoeke is gedoen na die JPEG2000 kompressie algoritme se bestandheid teen toevalsfoute, met klem op hoeveel die beeld gedegradeer word deur die bisfoute wat voorkom. Beide die kompressie en die foutkorreksie is ge-implementeer en aangewend op die toetsbeelde. Die foutkorreksie bestry die gesimuleerde toevalsfoute, soos wat dit op die kanaal voorkom. Die resultate toon dat die foutkorreksie die toevalsfoute met 'n faktor 100 verminder, en dat 'n foutwaarskynlikheid van 10-2 op die kanaal (10-4 op die beelddata) weinig degradering in die beeldkwaliteit veroorsaak.

Thesis (MScEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: This thesis describes various software technologies implemented, or specifically developed, for the SUNSAT micro-satellite mission. With the discussion centered on the Mission Operations System functions of Data Handling and Mission Control, particular emphasis is placed on data processing aspects such as the deployed database schema, and the data communications mechanisms implemented as part of the communications protocol stack. Both the groundsystem architecture and the Flight Software are discussed, their constituent components are analysed, and recommendations are made for improvement. Finally, a Unified Information Model for the design and operation of future, integrated satellite groundsystems is proposed, with suitable implementation technologies being identified and introduced. / AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die sagteware tegnologieë wat qeirnpternenteer. of spesifiek ontwerp is vir die SUNSAT mikro-satelliet missie, Met die bespreking gefokus op die Missie Operasionele Stelsel funksies van Data Hantering en Missie Beheer, word daar veral klem gelê op data prosesserings aspekte, soos byvoorbeeld die databasis skema wat ontplooi is, asook die data kommunikasie meganismes wat qeimplernenteer is as deel van die kommunikasie protokol stapel. Beide die grondstelsel argitektuur en die Vlugsagteware word bespreek, hulonderskeie komponente word geanaliseer, en aanbevelings ter verbetering word gemaak, Laastens word daar 'n Verenigde Informasie Model voorgestel vir die ontwerp en operasionele werking van 'n toekomstige, qeinteqreerde satelliet grondstelsel. Geskikte tegnologieë vir die implementasie hiervan word ook qeidentifiseer en voorgelê,

Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: The primary payload of the University of Stellenbosch's micro-satellite, SUNSAT I, was a high quality imager, capable of taking stereoscopic images of the surface of the earth. Although the orbit of SUNSAT I will have the satellite pass over the whole earth, contact via the SUNSAT I ground station at the University will only be made for 3% of each day. To be able to photograph any part of the earth onboard memory was provided on the satellite to store the image until it can be downloaded to the ground station. A high speed downlink was also added to the satellite to be able to download a complete image from the onboard memory in one pass and also to take realtime pictures as the satellite passes over the ground station. At that stage there was no way to capture the data at the ground station. A high speed digital data capture mechanism was needed. The thesis discusses the development of a high speed capture card. Due to the high speeds needed it provided an excellent opportunity to develop the card using the PCI bus, the first design to do so at the University, as an interface with a computer. A prototype card was developed first to do proof of concept. It is shown that the prototype card fulfilled the functional requirements and it was also used to capture the first image from the complete satellite during the final tests before launch. Finally a production card for use in the ground station was designed and assembled. / AFRIKAANSE OPSOMMING: Die hoof loonvrag van die Universtieit van Stellenbosch se eerste mikrosatelliet, SUNSAT I, is "n hoë kwaliteit kamera wat stereoskopiese fotos van die oppervlak van die aarde kan neem. Alhoewel die satelliet oor die hele oppervlakte van die aarde gaan beweeg, is dit vir slegs 3% van die dag sigbaar vanaf die grondstasie by die Universiteit van Stellenbosch. Om 'n foto van enige plek op aarde te kan neem is daar aanboord geheue op die satelliet geplaas om die foto te stoor totdat dit by die grondsatsie afgelaai kan word. "n Hoë spoed skakel is ook daargestelom die data in die geheue van die satelliet in een verbyvlug te kan aflaai. Dit stel die satelliet ook in staat om intydse fotos gedurende In verbyvlug van die satelliet te kan neem. Op daardie stadium het daar nog nie "n manier bestaan om die hoë spoed data vas te lê nie. In Meganisme om die hoë spoed digitale data te vang was nodig. Hierdie tesis bespreek die ontwikkeling van so In data vang kaart. Weens die hoë snelhede wat benodig word, het die PCI bus die ideale oplossing gebied om die data teen "n hoë spoed op In persoonlike rekenaar te stoor. Dit was ook die eerste ontwerp aan die Universiteit wat van die PCI bus gebruik gemaak het. In die eerste instansie is In prototipe ontwikkel om te bewys dat dit wel moontlik is om die data teen die benodigde tempo te kan stoor. Daar word gewys dat die prototipe aan die behoefte voldoen en dit is ook gebruik om die eerste beeld vanaf die volledige satelliet te vang voordat dit gelanseer is. In die tweede instansie word In produksiekaart ontwikkel en aanmekaar gesit.

Thesis (MScEng)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: South Africa's first micro satellite, SUNSAT, was operational in orbit for 23 months since its NASA-sponsored launch on February 23, 1999. SUNSAT is a graduate studentdeveloped satellite from the University of Stellenbosch in South Africa. Research work is in progress on improving SUNSAT's 15m multi-spectral imager to a 2.5m-resolution multi-sensor imager. This will require the use of Forward Motion Compensation for exposure control. This thesis presents Automatic Forward Motion Compensation for Micro Satellites using a new earth sensor that measures the bore-sight projection's speed on the earth directly. This sensor will have no drift and will make use of a series of images and crosscorrelation of them. The high-resolution imager's bore-sight motion can be controlled by this technique to ensure high quality stereo images. A control system based on the DLR-TUBSAT was designed and is simulated in MATLAB. This technique of measuring the bore-sight projection's speed on the earth directly was tested on a 2-axis telescope and used to measure random movement of a satellite. / AFRIKAANSE OPSOMMING: SUNSAT, Suid Afrika se eerste satelliet was vir 23 maande in werking in 'n wentelbaan na sy NASA-geborgde lasering op 23 Februarie 1999. SUNSAT is 'n satelliet wat ontwikkel is deur nagraadse studente aan die Universiteit van Stellenbosch. Navorsingswerk is aan die gang om SUNSAT se 15m resolusie multi-spektrale kamera te verbeter tot 'n 2.5m resolusie multi-sensor kamera. Die navorsing sal die gebruik van Voorwaartse Bewegingskompensasie benodig. Die tesis handeloor automatiese voorwaartse bewegingskompensasie vir mikrosatelliete deur gebruik te maak van 'n nuwe aardgerigte sensor, wat die siglyn projeksie se snelheid op die aarde direk sal meet. Die sensor sal gebruik maak van 'n reeks foto's wat gekruiskorreleer word en sal geen tempo-wegdrywing hê nie. Hoë resolusie kameras se siglyn kan deur middel van hierdie tegniek beheer word om hoë kwaliteit stereo foto's te verseker. 'n Beheerstelsel wat gebaseer is op dié van DLR-TUBSAT, is ontwerp en is gesimuleer in MATLAB. Die tegniek om die siglyn projeksie se snelheid op die aarde direk te meet, is getoets op 'n 2-as teleskoop en is gebruik om onverwille keurige beweging van 'n satelliet te meet.