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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

VHF Beacon Development, Ground Segment, and Operations for CanX Missions

Shah, Amee 15 February 2010 (has links)
The versatile Generic Nanosatellite Bus (GNB) technology fused with the Canadian Advanced Nanospace eXperiment (CanX) missions is pioneered by the Space Flight Laboratory (SFL) at University of Toronto Institute for Aerospace Studies. Microspace philosophy has been employed at SFL to develop low cost nanosatellites with emerging technologies for education and research. This thesis provides an insight to the space systems engineering experience acquired by the author being a master’s student at SFL. This thesis describes the design, construction and testing of the VHF beacon transmitter for GNB. The umbilical Electrical Ground Support Equipment (EGSE) designed and built by the author is presented in this thesis. The assembly, integration and testing of the SFL ground station for the CanX missions has been explored. The on-orbit spacecraft operations for CanX-2 and NTS, from the launch campaign to the commissioning phase to nominal operations along with the anomalies faced and the contingency operations carried out by the author to date have been explained in detail in this thesis.
12

Design and Development of Ground Segment Software and Hardware for Nanosatellie Space Missions

Mehradnia, Payam 05 December 2013 (has links)
Contributions to two nanosatellite missions are discussed. First, the design and development of a test system for an advanced nanosatellite power board is discussed. Details of software and hardware design process involved in the implementation of automated test procedures are presented. The system has been deployed for unit-level testing of power boards for several nanosatellite missions, significantly reducing testing cost and time. Next, a Mission Planning and Scheduling Software platform is proposed for Earth Observation missions. The motivation is described for the development of a stand-alone application enabling satellite operations teams to identify suitable observation scenario parameters. Attitude and orbital trajectory estimation algorithms constituting the computational model are integrated and implemented within a graphical visualization environment to allow interaction with the user in an efficient and intuitive manner. Key results of major component-level testing are presented, showing the behaviour and accuracy of analytical components satisfy mission requirements.
13

Thermal modelling of the PICSAT nanosatellite platform and synergetic prestudies of the CIRCUS nanosatellite

Flecht, Tobias January 2016 (has links)
In the present paper, which was written in collaboration with the Observatory of Paris, thermal models of two CubeSat missions were created. The first goal of this work was to create a nodal simulation of the PicSat satellite to verify the survivability of the system within the extreme space environment. In a second step suitable countermeasures were suggested, if parts of the satellite exceeded a critical temperature limit. Additionally, the impacts of three failure modes were investigated. The second goal was to perform thermal pre-studies of different satellite configurations of the CIRCUS satellite based on the model of PicSat. The simulation conducted in this work showed that PicSat fulfils its thermal requirements, except for three components. Out of the failure modes considered in this study, only an error of the attitude determination and control systems (ADCS) showed a critical impact on the thermal state of PicSat. As the outcome of the pre-studies of CIRCUS, two of the considered configurations were recommended for further analysis. The results of this work will contribute to the future development of the PicSat and CIRCUS missions. / Dans le cadre de ce mémoire, qui a été rédigé en collaboration avec l'Observatoire de Paris, les modèles thermiques de deux missions CubeSat ont été créés. Le premier objectif de ce projet était de d\'velopper une simulation nodale du satellite PicSat afin de vérifier la capacité de survie du système dans les conditions hostiles de l'espace. Dans un second temps, des mesures correctives ont été suggérées si la température de certaines sections du satellite venait à excéder une limite critique. En outre, les impacts de trois défaillances ont été analysés. Le second objectif était de réaliser des pré-études thermiques pour différentes configurations du satellite CIRCUS basées sur le modèle de PicSat. Les simulations réalisées dans le cadre de ce projet ont montré que PicSat remplit ses exigences thermiques, à l'exception de trois composants. Des différentes défaillances étudiées, seule une erreur du système de détermination et de contrôle d'attitude (Attitude Determination and Control System ADCS) a montré un impact critique sur l'état thermique de PicSat. A l'issue des pré-études de CIRCUS, deux des configurations étudiées ont été recommandées pour être l'objet d'une analyse plus avancée. Les résultats de ce projet contribueront au développement à venir des missions des satellites PicSat et CIRCUS.
14

Development of Vision Payload for the Nanosatellite VELOX-I

Kumar Kadarla, Vineel January 2012 (has links)
In the recent years, CubeSat’s are evolving from purely educational tools to a standard platform for technology demonstration and miniaturized scientific instrumentation. The use of COTS (Commercial-Off-The-Shelf) components aided the ongoing miniaturiza- tion of several technologies and demonstrated successfully. Furthermore advantages in this small satellite approach are due to their lesser development times and smaller sizes suitable for multiple CubeSat launches on a single launcher into their respective desig- nated orbits which is cost effective for Universities. These architectures not only promise the combination of both temporal resolution of GEO missions with spatial resolution of LEO missions, but also breaks the trade off in conventional Earth observation satel- lite designs. A thorough implementation of the firmware of vision payload of the Nano Satellite VELOX-I for the Earth observation and remote sensing purposes, in the near future with high scientific payoff is presented here. In course of implementation various case studies have been learned, current date CCSDS recommendations for image com- pression have been considered. Effect of key components such as power, memory and data transmission capability for small satellite remote sensing applications are discussed. Implementation of the core firmware of the payload and serial interface development in Java on Linux platform of Payload Processing Unit shall be able to inherit into the future VELOX missions. / <p>Validerat; 20121128 (global_studentproject_submitter)</p>
15

Analysis of single event radiation effects and fault mechanisms in SRAM, FRAM and NAND Flash : application to the MTCube nanosatellite project / Analyse des effets singuliers et des mécanismes de fautes dans des mémoires SRAM, FRAM et NAND Flash : application au projet de nanosatellite MTCube

Gupta, Viyas 06 July 2017 (has links)
L’environnement radiatif spatial est un environnement sévère qui agit sur tout composants électroniques embarqués sur des engins spatiaux, y compris sous le bouclier naturel que nous procure le champ magnétique terrestre en orbite basse. Bien qu’il soit possible, en particulier à ces orbites, de se protéger efficacement contre les particules créant de la dose totale ionisante, cela pose plus de difficultés pour les particules générant des effets singuliers. Cela est d’autant plus un problème que l’utilisation des composants commerciaux (dits « COTS »), non conçus pour de telles applications, sont de plus en plus utilisés. Dans le cadre de cette thèse, les effets singuliers sur trois types de mémoires sont étudiés: SRAM, FRAM et NAND Flash. En se basant sur l’analyse des résultats de tests, les mécanismes d’erreurs induits par des particules générant des effets singuliers sont analysés. Avec pour objectif d’étudier et comparer la sensibilité de ces mémoires directement en orbite, l’expérience RES (Radiation Effect Study) a été développée et est présentée dans ce manuscrit. Cette expérience scientifique constituera la charge utile du nanosatellite de type CubeSat nommé MTCube (Memory Test CubeSat) developpé à l’Université de Montpellier en collaboration entre le Centre Spatial Universitaire Montpellier-Nîmes, et les laboratoires LIRMM et IES. Ce nanosatellite est financé par l’ESA (Agence Spatial Européenne). / Space radiation is a harsh environment affecting all electronic devices used on spacecraft, despite the presence of Earth’s protective magnetic field in Low Earth Orbit (LEO). Although particles inducing total ionizing dose (TID) can be effectively shielded against in LEO, particles responsible for Single Event Effects (SEEs) remain an issue for the reliability of electronics. This is particularly of concern considering the increasing use of Commercial-Off-The-Shelf (COTS) components, not designed for space applications. In the frame of this thesis, the SEE response of three commercial memory types are explored: SRAM, FRAM and NAND Flash. Based on SEE test results, the possible fault mechanisms induced by SEE particles on those devices are analysed. In order to study and compare the devices’ response with actual in-orbit measurements, the RES (Radiation Effect Study) science experiment was developed and is presented. The RES experiment will be the payload of the MTCube (Memory Test CubeSat) nanosatellite, which is being developed at the University of Montpellier as a joint project between the University Space Center (CSU Montpellier-Nîmes), as well as the LIRMM and IES laboratories. MTCube is financed by the European Space Agency (ESA).
16

Design of a deployable tape spring half wavelength dipole antenna for the ORCASat nanosatellite

Buzas, Levente Imre 21 January 2022 (has links)
The focus of this thesis is the design, manufacturing and testing of a deployable radio antenna for the ORCASat nanosatellite. First, the context, motivation, requirements, as well as constraints for this project are introduced. Next, a brief overview of theoretical concepts relevant to the contents of this thesis are presented. After the introduction of the relevant background and theory, a literature review is undertaken, and an experiment-based methodology is established. Prior to conceptualizing a new design, detailed consideration is also given to previous attempts at designing a dipole for ORCASat. The root cause of the problems with these attempts is determined experimentally as the presence of ground planes on the circuit board supporting the antenna. After this preliminary investigation, the blocks required for the ORCASat antenna are introduced as the transmission line feeder, the balun, the impedance matching block, and the antenna arm feed. For each of these components, competing design concepts are developed, and the advantages and disadvantages of each of these concepts are presented. After this, the winning design concept is selected and developed into a manufacturable design. This design is identified as a tunable tape spring half wave dipole antenna featuring a specialized feed with electrically and mechanically optimal characteristics, no impedance matching, and a lossy choke balun wound from the coaxial cable feeder, all mounted on a circuit board in a pre-existing Delrin antenna deployer. Next, the manufacturing and assembly of this design is undertaken, followed by the consideration of an informal commissioning procedure. As part of this, a test article consisting of an incomplete prototype of the dipole is tested, and it is shown to have desirable voltage standing wave ratio, input impedance, and return loss characteristics, as well as excellent tunability. Having established that this test article is a good candidate to meet project requirements, it is updated to include as many of the final components of the antenna as possible. Then, formal test procedures for the verification of the tunability, return loss, VSWR, input impedance, antenna pattern, and absolute gain are established, and executed. Based on the results of this formal verification test campaign, it is concluded that the test article meets the requirements presented at the beginning of this thesis, and it is suitable as a radio antenna for the ORCASat mission. After this, the work is concluded by a set of recommendations for future work to prepare the antenna developed in this thesis for flight. / Graduate
17

High Performance Attitude Determination and Control for Nanosatellite Missions

Johnston-Lemke, Bryan 08 December 2011 (has links)
Small satellites are growing in popularity because they offer an effective option that enables missions otherwise too schedule or cost limited. However, many possible missions require improved platform capabilities without sacrificing the cost effective nature of small satellites before they become viable. Described is the development and validation of high performance attitude determination and control for nanosatellite missions. Considered are astronomy missions, requiring very fine pointing stability, and formation flying missions requiring rapid manoeuvring while maintaining antenna coverage towards secondary pointing targets. It will be shown that power and volume limited nanosatellites are capable of this level of attitude performance by leveraging the techniques normally reserved for larger spacecraft. Discussed are attitude state estimation techniques and control laws developed for the BRITE stellar photometry constellation and CanX-4 and CanX-5 formation flying mission, along with the challenges associated with implementing and validating these designs for real space missions.
18

Next Generation Nanosatellite Systems: Mechanical Analysis and Test

Ligori, Michael C. 14 December 2011 (has links)
The Canadian Nanosatellite Advanced Propulsion System is the second generation cold-gas propulsion system. Its purpose is to provide the millinewton thrust required for formation control of nanosatellites, in particular the CanX-4/-5 formation flying mission. Additionally, to inject nanosatellites into orbit, a reliable and robust deployer is needed to bridge the gap between the launch vehicle and space. This bridge is the XPOD, the eXoadaptable PyrOless Deployer. Both of these technologies are designed and developed by the Space Flight Lab. This thesis describes the assembly, integration and preliminary testing of the CanX-4/-5 propulsion system. Emphasis is placed on the phases involved with the assembly and integration while highlighting the problems encountered and lessons learned. In addition, the mechanical analysis of the XPOD as well as its assembly and testing is described in detail.
19

High Performance Attitude Determination and Control for Nanosatellite Missions

Johnston-Lemke, Bryan 08 December 2011 (has links)
Small satellites are growing in popularity because they offer an effective option that enables missions otherwise too schedule or cost limited. However, many possible missions require improved platform capabilities without sacrificing the cost effective nature of small satellites before they become viable. Described is the development and validation of high performance attitude determination and control for nanosatellite missions. Considered are astronomy missions, requiring very fine pointing stability, and formation flying missions requiring rapid manoeuvring while maintaining antenna coverage towards secondary pointing targets. It will be shown that power and volume limited nanosatellites are capable of this level of attitude performance by leveraging the techniques normally reserved for larger spacecraft. Discussed are attitude state estimation techniques and control laws developed for the BRITE stellar photometry constellation and CanX-4 and CanX-5 formation flying mission, along with the challenges associated with implementing and validating these designs for real space missions.
20

Next Generation Nanosatellite Systems: Mechanical Analysis and Test

Ligori, Michael C. 14 December 2011 (has links)
The Canadian Nanosatellite Advanced Propulsion System is the second generation cold-gas propulsion system. Its purpose is to provide the millinewton thrust required for formation control of nanosatellites, in particular the CanX-4/-5 formation flying mission. Additionally, to inject nanosatellites into orbit, a reliable and robust deployer is needed to bridge the gap between the launch vehicle and space. This bridge is the XPOD, the eXoadaptable PyrOless Deployer. Both of these technologies are designed and developed by the Space Flight Lab. This thesis describes the assembly, integration and preliminary testing of the CanX-4/-5 propulsion system. Emphasis is placed on the phases involved with the assembly and integration while highlighting the problems encountered and lessons learned. In addition, the mechanical analysis of the XPOD as well as its assembly and testing is described in detail.

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