To see the other types of publications on this topic, follow the link: Cubesat development.
Dissertations / Theses on the topic 'Cubesat development'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Cubesat development.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Erlank, Alexander Olaf. "Development of CubeStar : a CubeSat-compatible star tracker." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85746.
Full textAbstract:
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.
2
Cheney, Liam Jon. "Development of Safety Standards for CubeSat Propulsion Systems." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1180.
Full textAbstract:
The CubeSat community has begun to develop and implement propulsion systems. This movement represents a new capability which may satisfy mission needs such as orbital and constellation maintenance, formation flight, de-orbit, and even interplanetary travel. With the freedom and capability granted by propulsion systems, CubeSat providers must accept new responsibilities in proportion to the potential hazards that propulsion systems may present.
The Cal Poly CubeSat program publishes and maintains the CubeSat Design Specification (CDS). They wish to help the CubeSat community to safety and responsibly expand its capabilities to include propulsive designs. For this reason, the author embarked on the task of developing a draft of safety standards CubeSat propulsion systems.
Wherever possible, the standards are based on existing documents. The author provides an overview of certain concepts in systems safety with respect to the classification of hazards, determination of required fault tolerances, and the use of inhibits to satisfy fault tolerance requirements. The author discusses hazards that could exist during ground operations and through launch with respect to hazardous materials and pressure systems. Most of the standards related to Range Safety are drawn from AFSPCMAN 91-710. Having reviewed a range of hypothetical propulsion system architectures with an engineer from Range Safety at Vandenberg Air Force Base, the author compiled a case study. The author discusses many aspects of orbital safety. The author discusses the risk of collision with the host vehicle and with third party satellites along with the trackability of CubeSats using propulsion systems. Some recommendations are given for working with the Joint Functional Component Command for Space (JFCC SPACE), thanks to the input of two engineers who work with the Joint Space Operations Center (JSpOC). Command Security is discussed as an important aspect of a mission which implements a propulsion system. The author also discusses End-of-Life procedures such as safing and de-orbit operations. The orbital safety standards are intended to promote “good citizenship.”
The author steps through each proposed standard and offers justification. The author is confident that these standards will set the stage for a dialogue in the CubeSat community which will lead to the formulation of a reasonable and comprehensive set of standards. The author hopes that the discussions given throughout this document will help CubeSat developers to visualize the path to flight readiness so that they can get started on the right foot.
3
Lumbwe, Lwabanji Tony. "Development of an onboard computer (OBC) for a CubeSat." Thesis, Cape Peninsula University of Technology, 2013. http://hdl.handle.net/20.500.11838/1172.
Full textAbstract:
Over the past decade, the satellite industry has witnessed the birth and evolution of the
CubeSat standard, not only as a technology demonstrator tool but also as a human capacity
development platform in universities. The use of commercial off the shelf (COTS) hardware
components makes the CubeSat a cost effective and ideal solution to gain access to space in
terms of budget and integration time for experimental science payloads.
Satellite operations are autonomous and are essentially based on the interaction of
interconnected electronic subsystems exchanging data according to the mission requirements
and objectives. The onboard computer (OBC) subsystem is developed around a microcontroller
and plays an essential role in this exchange process as it performs all the computing tasks and
organises the collection of onboard housekeeping and payload data before downlink during an
overpass above the ground station.
The thesis here presented describes the process involved in the development, design and
implementation of a prototype OBC for a CubeSat. An investigation covering previously
developed CubeSat OBCs is conducted with emphasis on the characteristics and features of
the microcontroller to be used in the design and implementation phases. A set of hardware
requirements are defined and according to the current evolution on the microcontroller market,
preference is given to the 32-bit core architecture over both its 8-bit and 16-bit counterparts.
Following a well defined selection process, Atmel’s AT91SAM3U4E microcontroller which
implements a 32-bit Cortex-M3 core is chosen and an OBC architecture is developed around it.
Further, the proposed architecture is implemented as a prototype on a printed circuit board
(PCB), presenting a set of peripherals necessary for the operation of the OBC. Finally, a series
of tests successfully conducted on some of the peripherals are used to evaluate the proposed
architecture.
4
Zohar, Guy G. "AD-HOC REGIONAL COVERAGE CONSTELLATIONS OF CUBESATS USING SECONDARY LAUNCHES." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/927.
Full textAbstract:
As development of CubeSat based architectures increase, methods of deploying constellations of CubeSats are required to increase functionality of future systems. Given their low cost and quickly increasing launch opportunities, large numbers of CubeSats can easily be developed and deployed in orbit. However, as secondary payloads, CubeSats are severely limited in their options for deployment into appropriate constellation geometries.
This thesis examines the current methods for deploying cubes and proposes new and efficient geometries using secondary launch opportunities. Due to the current deployment hardware architecture, only the use of different launch opportunities, deployment direction, and deployment timing for individual cubes in a single launch are explored. The deployed constellations are examined for equal separation of Cubes in a single plane and effectiveness of ground coverage of two regions. The regions examined are a large near-equatorial zone and a medium sized high latitude, high population density zone.
Results indicate that simple deployment strategies can be utilized to provide significant CubeSat dispersion to create efficient constellation geometries. The same deployment strategies can be used to develop a multitude of differently dispersed constellations. Different launch opportunities can be utilized to tailor a constellation for a specific region or mission objective. Constellations can also be augmented using multiple launch opportunities to optimize a constellation towards a specific mission or region. The tools developed to obtain these results can also be used to perform specific analysis on any region in order to optimize future constellations for other applications.
5
Royo, Serrano Daniel. "Development of a calibration procedure for gyroscopes in CubeSat missions." Thesis, Luleå tekniska universitet, Rymdteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-83278.
Full text
6
Persson, Marcus. "Software Development and Qualification Testing of a CubeSat X-ray Monitor." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-76843.
Full textAbstract:
The CUBES (CUbesat x-ray Background Explorer using Scintillators) is a payload on the KTH student satellite MIST (MIniature STudent satellite) to evaluate Silicon Photo-multiplier technology and new scintillators such as GAGG (Gadolinium Aluminium Gallium Garnet, Gd3Al2Ga3O12) for future use in hard X-ray polarisation studies of Gamma-Ray Bursts. CUBES itself is designed to study the MIST in-orbit radiation environment by using a detector which is comprised of a silicon photomultiplier coupled to different scintillator materials. Three of these detectors will be mounted on the payload platform and then coupled to inputs of an Application Specific Integrated Circuit (ASIC) and connected to a Field-programmable Gate Array (FPGA) which will store and send data through the downlink on the MIST satellite to ground. This thesis covers the software development for the FPGA, together with two radiation tests of components and the preparation of these.CUBES
MIST
7
Botma, Pieter Johannes. "The design and development of an ADCS OBC for a CubeSat." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/18040.
Full textAbstract:
Thesis (MScEng)--Stellenbosch University, 2011.ENGLISH ABSTRACT: The Electronic Systems Laboratory at Stellenbosch University is currently developing a fully 3-axis controlled Attitude Determination and Control Subsystem (ADCS) for CubeSats. This thesis describes the design and development of an Onboard Computer (OBC) suitable for ADCS application. A separate dedicated OBC for ADCS purposes allows the main CubeSat OBC to focus only on command and data handling, communication and payload management. This thesis describes, in detail the development process of the OBC. Multiple Microcontroller Unit (MCU) architectures were considered before selecting an ARM Cortex-M3 processor due to its performance, power efficiency and functionality. The hardware was designed to be as robust as possible, because radiation tolerant and redundant components could not be included, due to their high cost and the technical constraints of a CubeSat. The software was developed to improve recovery from lockouts or component failures and to enable the operational modes to be configured in real-time or uploaded from the ground station. Ground tests indicated that the OBC can handle radiation-related problems such as latchups and bit-flips. The peak power consumption is around 500 mW and the orbital average is substantially lower. The proposed OBC is therefore not only sufficient in its intended application as an ADCS OBC, but could also stand in as a backup for the main OBC in case of an emergency.
AFRIKAANSE OPSOMMING: Die Elektroniese Stelsels Laboratorium by die Universiteit van Stellenbosch is tans besig om ’n volkome 3-as gestabiliseerde oriëntasiebepaling en -beheerstelsel (Engels: ADCS) vir ’n CubeSat te ontwikkel. Hierdie tesis beskryf die ontwerp en ontwikkeling van ’n aanboordrekenaar (Engels: OBC) wat gebruik kan word in ’n ADCS. ’n Afsonderlike OBC wat aan die ADCS toegewy is, stel die hoof-OBC in staat om te fokus op beheer- en datahantering, kommunikasie en loonvragbestuur. Hierdie tesis beskryf breedvoerig die werkswyse waarvolgens die OBC ontwikkel is. Verskeie mikroverwerkers is as moontlike kandidate ondersoek voor daar op ’n ARM Cortex-M3-gebaseerde mikroverwerker besluit is. Hierdie mikroverwerker is gekies vanweë sy spoed, effektiewe kragverbruik en funksionaliteit. Die hardeware is ontwikkel om so robuust moontlik te wees, omdat stralingbestande en oortollige komponente weens kostebeperkings, asook tegniese beperkings van ’n CubeSat, nie ingesluit kon word nie. Die programmatuur is ontwikkel om van ’n uitsluiting en ’n komponentfout te kan herstel. Verder kan programme wat tydens vlug in werking is, verstel word en vanaf ’n grondstasie gelaai word. Grondtoetse het aangedui dat die OBC stralingverwante probleme, soos ’n vergrendeling (latchup) of bis-omkering (bit-flip), kan hanteer. Die maksimum kragverbruik is ongeveer 500 mW en die gemiddelde wentelbaankragverbruik is beduidend kleiner. Die voorgestelde OBC is dus voldoende as ADCS OBC asook hoof-OBC in geval van nood.
8
Mey, Philip Hendrik. "Development of attitude controllers and actuators for a solar sail cubesat." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6862.
Full textAbstract:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011.ENGLISH ABSTRACT: CubeSats are small, lightweight satellites which are often used by academic institutions due to their application potential and low cost. Because of their size and weight, less powerful attitude controllers, such as solar sails, can be used. In 2010, the Japanese satellite, Ikaros, was launched to illustrate the usage of solar sails as a propulsion system. Similarly, by exploiting the solar radiation pressure, it is possible to use a solar sail, together with three magnetorquers, to achieve 3-axis attitude control of a 3-unit CubeSat. Simulations are required to demonstrate the attitude control of a sun-synchronous, low Earth orbit CubeSat using a solar sail. To allow the adjustment of the solar sail, and its resulting torque, a mechanical structure is required which can be used to position the sail within two orthogonal axes. Although the magnetorquers and solar sail are sufficient to achieve 3-axis attitude control, the addition of a reaction wheel can be implemented in an attempt to improve this control.
AFRIKAANSE OPSOMMING: CubeSats is klein, ligte satelliete wat dikwels deur universiteite gebruik word weens hul lae koste en groot toepassings potensiaal. As gevolg van hulle gewig en grootte, kan minder kragtige posisie beheerders, soos byvoorbeeld sonseile, gebruik word. Die Japannese satelliet, Ikaros, was in 2010 gelanseer om die gebruik van ’n sonseil as aandrywingstelsel te illustreer. Net so is dit moontlik om die bestraling van die son te gebruik, met behulp van ’n sonseil, en drie magneetstange om 3-as posisiebeheer op ’n 3-eenheid CubeSat te bekom. Simulasies word benodig om die posisie beheer van ’n sonsinkrone, lae-aard wentelbaan CubeSat met ’n sonseil te demonstreer. ’n Meganiese struktuur word benodig vir die posisionering van die sonseil in twee ortogonale asse sodat die sonseil, en dus die geassosieerde draaimoment, verskuif kan word. Alhoewel die magneetstange en sonseil voldoende is om 3-as posisiebeheer te bekom, kan ’n reaksiewiel bygevoeg word om hierdie beheer te probeer verbeter.
9
Abel, John Trevor. "Development of a CubeSat Instrument for Microgravity Particle Damper Performance Analysis." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/537.
Full textAbstract:
Spacecraft pointing accuracy and structural longevity requirements often necessitate auxiliary vibration dissipation mechanisms. However, temperature sensitivity and material degradation limit the effectiveness of traditional damping techniques in space. Robust particle damping technology offers a potential solution, driving the need for microgravity characterization. A 1U cubesat satellite presents a low cost, low risk platform for the acquisition of data needed for this evaluation, but severely restricts available mass, volume, power and bandwidth resources. This paper details the development of an instrument subject to these constraints that is capable of capturing high resolution frequency response measurements of highly nonlinear particle damper dynamics.
10
Loubser, Hanco Evert. "The development of Sun and Nadir sensors for a solar sail CubeSat." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6748.
Full textAbstract:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011.ENGLISH ABSTRACT: This thesis describes the development of attitude sensors required for the Attitude Determination and Control System (ADCS) for a Cubesat. The aim is to find the most suitable sensors for use on a small picosatellite by implementing miniaturised sensors with available commercial-off-the-shelf (COTS) technology. Specifically, the algorithms, hardware prototypes, software and filters required to create accurate sensors to determine the 3-axis orientation of a CubeSat are discussed.
AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die ontwikkeling van oriëntasiesensors wat benodig word vir die oriëntasiebepaling en -beheerstelsel (Engels: ADCS) van ’n CubeSat. Die doelwit is om sensors te vind wat die geskikste is om in ’n klein picosatelliet te gebruik, deur miniatuursensors met kommersiële maklik verkrygbare tegnologie (Engels: COTS technology) te implementeer. Daar word in die bespreking veral aandag geskenk aan die algoritmes, hardewareprototipes, programmatuur en filters wat benodig word om akkurate sensors te skep wat op hul beurt 3-as oriëntasie van die CubeSat kan bepaal.
11
Doering, Tyler James. "DEVELOPMENT OF A REUSABLE CUBESAT SATELLITE BUS ARCHITECTURE FOR THE KYSAT-1 SPACECRAFT." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_theses/584.
Full textAbstract:
This thesis describes the design, implementation and testing of a spacecraft bus implemented on KySat-1, a picosatellite scheduled to launch late 2009 to early 2010. The spacecraft bus is designed to be a robust reusable bus architecture using commercially available off the shelf components and subsystems. The bus designed and implemented for the KySat-1 spacecraft will serve as the basis for a series of future Kentucky Space Consortium missions. The spacecraft bus consists of attitude determination and control subsystem, communications subsystem, command and data handling subsystem, thermal subsystem, power subsystem, and structures and mechanisms. The spacecraft bus design is described and the implementation and testing and experimental results of the integrated spacecraft engineering model. Lessons learned with the integration, implementation, and testing using commercial off the shelf components are also included. This thesis is concluded with future spacecraft bus improvements and launch opportunity of the implemented spacecraft, KySat-1.
12
Gonzalez-Dorbecker, MaryCarmen. "DEVELOPMENT OF TOOLS NEEDED FOR RADIATION ANALYSIS OF A CUBESAT DEPLOYER USING OLTARIS." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1501.
Full textAbstract:
Currently, the CubeSat spacecraft is predominantly used for missions at Low- Earth Orbit (LEO). There are various limitations to expanding past that range, one of the major ones being the lack of sufficient radiation shielding on the Poly-Picosatellite Orbital Deployer (P-POD). The P-POD attaches to a launch vehicle transporting a primary spacecraft and takes the CubeSats out into their orbit. As the demand for interplanetary exploration grows, there is an equal increase in interest in sending CubeSats further out past their current regime. In a collaboration with NASA’s Jet Propulsion Laboratory (JPL), students from the Cal Poly CubeSat program worked on a preliminary design of an interplanetary CubeSat deployer, the Poly-Picosatellite Deep Space Deployer (PDSD). Radiation concerns were mitigated in a very basic manner, by simply increasing the thickness of the deployer wall panels. While this provided a preliminary idea for improved radiation shielding, full analysis was not conducted to determine what changes to the current P-POD are necessary to make it sufficiently radiation hardened for interplanetary travel.
This thesis develops a tool that can be used to further analyze the radiation environment concerns that come up with interplanetary travel. This tool is the connection between any geometry modeled in CAD software and the radiation tool OLTARIS (On- Page iv Line Tool for the Assessment of Radiation In Space). It reads in the CAD file and converts it into MATLAB, at which point it can then perform ray-tracing analysis to get a thickness distribution at any user-defined target points. This thickness distribution file is uploaded to OLTARIS for radiation analysis of the user geometry.
To demonstrate the effectiveness of the tool, the radiation environment that a CubeSat sees inside of the current P-POD is characterized to create a radiation map that CubeSat developers can use to better design their satellites. Cases were run to determine the radiation in a low altitude orbit compared to a high altitude orbit, as well as a Europa mission. For the LEO trajectory, doses were seen at levels of 102 mGy, while the GEO trajectory showed results at one order of magnitude lower. Electronics inside the P-POD can survive these doses with the current design, confirming that Earth orbits are safe for CubeSats. The Europa- Jovian Tour mission showed results on a higher scale of 107 mGy, which is too high for electronics in the P-POD. Additional cases at double the original thickness and 100 times the original thickness resulted in dose levels at orders of about 107 and 104 mGy respectively. This gives a scale to work off for a “worst case” scenario and provides a path forward to modifying the shielding on deployers for interplanetary missions. Further analysis is required since increasing the existing P-POD thickness by 100 times is unfeasible from both size and mass perspectives. Ultimately, the end result is that the current P-POD standard does not work too far outside of Earth orbits. Radiation-based changes in the design, materials, and overall shielding of the P- POD need to be made before CubeSats can feasibly perform interplanetary missions.
13
Heunis, Andre Emile. "Design and implementation of generic flight software for a CubeSat." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95911.
Full textAbstract:
Thesis (MEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: The main on-board computer in a satellite is responsible for ensuring the correct operation of the entire system. It performs this task using flight software. In order to reduce future development costs, it is desirable to develop generic software that can be re-used on subsequent missions. This thesis details the design and implementation of a generic flight software application for CubeSats. A generic, modular framework is used in order to increase the re-usability of the flight software architecture. In order to simplify the management of the various on-board processes, the software is built upon the FreeRTOS real-time operating system. The Consultative Committee for Space Data Systems’ telemetry and telecommand packet definitions are used to interface with ground stations. In addition, a number of services defined in the European Cooperation for Space Standardisation’s Packet Utilisation Standard are used to perform the functions required from the flight software. The final application contains all the command and data handling functionality required in a standard CubeSat mission. Mechanisms for the collection, storage and transmission of housekeeping data are included as well as the implementation of basic fault tolerance techniques. Through testing it is shown that the FreeRTOS scheduler can be used to ensure the software meets hard-real time requirements.
AFRIKAANSE OPSOMMING: Die hoof aanboordrekenaar in ’n satelliet verseker die korrekte werking van die hele stelsel. Die rekenaar voer hierdie taak uit deur van vlugsagteware gebruik te maak. Om toekomstige ontwikkelingskostes te verminder, is dit noodsaaklik om generiese sagteware te ontwikkel wat hergebruik kan word op daaropvolgende missies. Hierdie tesis handel oor die besonderhede van die ontwerp en implementering van generiese vlugsagteware vir ’n CubeSat. ’n Generiese, modulêre raamwerk word gebruik om die hergebruik van die sagteware te verbeter. Ten einde die beheer van die verskillende aanboordprosesse te vereenvoudig, word die sagteware gebou op die FreeRTOS reëletyd bedryfstelsel. Die telemetrie- en telebevelpakket definisies van die “Consultative Committee for Space Data Systems” word gebruik om met grondstasies te kommunikeer. Daarby is ’n aantal dienste omskryf in die “Packet Utilisation Standard” van die “European Cooperation for Space Standardisation” gebruik om die vereiste funksies van die vlugsagteware uit te voer. Die finale sagteware bevat al die bevel en data-hantering funksies soos wat vereis word van ’n standaard CubeSat missie. Meganismes vir die versameling, bewaring en oordrag van huishoudelike data is ingesluit sowel as die implementering van basiese fouttolerante tegnieke. Toetse het gewys dat die FreeRTOS skeduleerder gebruik kan word om te verseker dat die sagteware aan harde reëletyd vereistes voldoen.
14
Bodnarik, Julia G., Dave Hamara, Michael Groza, Ashley C. Stowe, Arnold Burger, Keivan G. Stassun, Liviu Matei, Joanna C. Egner, Walter M. Harris, and Vladimir Buliga. "Neutron detector development for microsatellites." SPIE-INT SOC OPTICAL ENGINEERING, 2017. http://hdl.handle.net/10150/627176.
Full textAbstract:
We present a preliminary design for a novel neutron detection system that is compact, lightweight, and low power consuming, utilizing the CubeSat platform making it suitable for space-based applications. This is made possible using the scintillating crystal lithium indium diselenide ((LiInSe2)-Li-6), the first crystal to include Li-6 in the crystalline structure, and a silicon avalanche photodiode (Si-APD). The schematics of this instrument are presented as well as the response of the instrument to initial testing under alpha, gamma and neutron radiation. A principal aim of this work is to demonstrate the feasibility of such a neutron detection system within a CubeSat platform. The entire end-to-end system presented here is 10 cm x 10 cm x 15 cm, weighs 670 grams and requires 5 V direct current at 3 Watts.
15
Parobek, Lucas S. "RESEARCH, DEVELOPMENT AND TESTING OF A FAULT-TOLERANT FPGA-BASED SEQUENCER FOR CUBESAT LAUNCHING APPLICATIONS." Monterey, California. Naval Postgraduate School, 2013. http://hdl.handle.net/10945/32882.
Full textAbstract:
This thesis concerns various means of implementing fault tolerance in logic for use in a general payload processor design. The first specific application of this research is a sequencer developed for deploying CubeSats. The sequencer shall be capable of the timing and accurate deployment of multiple CubeSats from a host spacecraft and shall have the capability for quick reconfiguration prior to launch. This research considers a variety of hardware for suitability toward sequencer construction; field programmable gate arrays (FPGAs) are chosen as the primary device. The design further evolves to selection of the Actel ProASIC3 series of FPGAs. Initial logic test configurations are implemented on a development kit with analysis of results provided. Fault-tolerant techniques are compared with a set of experiments to determine optimum resource utilization and timing schemes. Triple modular redundancy (TMR) is selected as the technique for fault-tolerant logic implementation in the sequencer. Preliminary test boards are built via schematic design and printed circuit board layout. The manufacturing, integration and testing of the ProASIC3 Test Board is fully discussed. A follow-on flight prototype board is designed with more extensive hardware allowing for implementation of fault-tolerant techniques and future growth capability. Recommendations for future work are discussed.
16
Vasudevan, Siddarth. "Design and Development of a CubeSat Hardware Architecture with COTS MPSoC using Radiation Mitigation Techniques." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-285577.
Full textAbstract:
CubeSat missions needs components that are tolerant against the radiation in space. The hardware components must be reliable, and it must not compromise the functionality on-board during the mission. At the same time, the cost of hardware and its development should not be high. Hence, this thesis discusses the design and development of a CubeSat architecture using a Commercial Off-The- Shelf (COTS) Multi-Processor System on Chip (MPSoC). The architecture employs an affordable Rad-Hard Micro-Controller Unit as a Supervisor for the MPSoC. Also, it uses several radiation mitigation techniques such as the Latch-up protection circuit to protect it against Single-Event Latch-ups (SELs), Readback scrubbing for Non- Volatile Memories (NVMs) such as NOR Flash and Configuration scrubbing for the FPGA present in the MPSoC to protect it against Single-Event Upset (SEU)s, reliable communication using Cyclic Redundancy Check (CRC) and Space packet protocol. Apart from such functionalities, the Supervisor executes tasks such as Watchdog that monitors the liveliness of the applications running in the MPSoC, data logging, performing Over-The-Air Software/Firmware update. The thesis work implements functionalities such as Communication, Readback memory scrubbing, Configuration scrubbing using SEM-IP, Watchdog, and Software/Firmware update. The execution times of the functionalities are presented for the application done in the Supervisor. As for the Configuration scrubbing that was implemented in Programmable Logic (PL)/FPGA, results of area and latency are reported.CubeSat-uppdrag behöver komponenter som är toleranta mot strålningen i rymden. Maskinvarukomponenterna måste vara pålitliga och funktionaliteten ombord får inte äventyras under uppdraget. Samtidigt bör kostnaden för hårdvara och dess utveckling inte vara hög. Därför diskuterar denna avhandling design och utveckling av en CubeSatarkitektur med hjälp av COTS (eng. Custom-off-The-Shelf) MPSoC (eng. Multi Processor System-on-Chip). Arkitekturen använder en prisvärd strålningshärdad (eng. Rad-Hard) Micro-Controller Unit(MCU) som Övervakare för MPSoC:en och använder också flera tekniker för att begränsa strålningens effekter såsom kretser för att skydda kretsen från s.k. Single Event Latch-Ups (SELs), återläsningsskrubbning för icke-volatila minnen (eng. Non-Volatile Memories) NVMs som NOR Flash och skrubbning av konfigurationsminnet skrubbning för FPGA:er i MPSoC:en för att skydda dem mot Single-Event Upsets (SEUs), och tillhandahålla pålitlig kommunikation mha CRC och Space Packet Protocol. Bortsett från sådana funktioner utför Övervakaren uppgifter som Watchdog för att övervaka att applikationerna som körs i MPSoC:en fortfarande är vid liv, dataloggning, och Over- the-Air-uppdateringar av programvaran/Firmware. Examensarbetet implementerar funktioner såsom kommunikation, återläsningsskrubbning av minnet, konfigurationsminnesskrubbning mha SEM- IP, Watchdog och uppdatering av programvara/firmware. Exekveringstiderna för utförandet av funktionerna presenteras för den applikationen som körs i Övervakaren. När det gäller konfigurationsminnesskrubbningen som implementerats i den programmerbara logiken i FPGA:n, rapporteras area och latens.
17
Eatchel, A. L., R. Fevig, C. Cooper, J. Gruenenfelder, and J. Wallace. "DEVELOPMENT OF A BASELINE TELEMETRY SYSTEM FOR THE CUBESAT PROGRAM AT THE UNIVERSITY OF ARIZONA." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/607488.
Full textAbstract:
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, CaliforniaA telemetry system has been developed at the University of Arizona to serve as a baseline for future CubeSat designs. Two satellites are scheduled for launch in November of 2002. One features a beacon that operates autonomously of all but the power system and can independently deploy the antennas. The other will test the performance of new semiconductor devices in low earth orbit. Sensors will monitor voltages, currents (from which attitude and tumble rate can be derived), received signal strength and a distribution of temperatures. The CubeSat’s architecture, operating system, sensors, telemetry format and link budget are discussed.
18
Ledo, López Guillermo. "Development and Implementation of a Mass Balancing System for CubeSat Attitude Hardware-in-the-Loop Simulations." Thesis, Luleå tekniska universitet, Rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72351.
Full textAbstract:
Spacecraft simulator platforms can simulate the microgravity environment of space on Earth, for the purposes of testing the Attitude and Orbit Control Subsystem of satellites. In order to do this, the satellite is mounted on a bench and the combined center of mass of this assembly is controlled by a series of moving masses. The objective is to bring this center or mass as close as possible to the center of rotation, since solids in microgravity always rotate around their own center of mass. The air-bearing platform located, designed and built at the NanoSat Laboratory of the Kiruna Space Campus of the Luleå University of Technology makes use of four balancing masses, which are displaced by that number of linear actuators. This document explains the process followed to design an algorithm for the estimation of the center of mass and the subsequent calculation of the required positions of the balancing masses to bring this center of mass back to the center of rotation. First, the equations of rotational motion of the bench were found through two formulations: quaternions and Euler-Lagrange. Secondly, these equations were used to obtain an estimation of the center of mass via Batch Least-Squares. Thirdly, the equations of the center of mass of a system of point masses were used to find the proper positions of the balancing masses. Finally, the complete algorithm was tested with Hardware-in-the-Loop simulations before testing it in the real hardware of the platform. The developed algorithm was not capable of estimating the center of mass with sufficient accuracy, which invalidated the obtained actuator positions, and thus was not able to compensate the offset of the center of mass. Recommended lines of development are provided to assist on the continuation of this work.
19
Bruno, Liam T. "Three Axis Attitude Control System Design and Analysis Tool Development for the Cal Poly CubeSat Laboratory." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2288.
Full textAbstract:
The Cal Poly CubeSat Laboratory (CPCL) is currently facing unprecedented engineering challenges—both technically and programmatically—due to the increasing cost and complexity of CubeSat flight missions. In responding to recent RFPs, the CPCL has been forced to find commercially available solutions to entire mission critical spacecraft subsystems such as propulsion and attitude determination & control, because currently no in-house options exist for consideration. The commercially available solutions for these subsystems are often extremely expensive and sometimes provide excessively good performance with respect to mission requirements. Furthermore, use of entire commercial subsystems detracts from the hands-on learning objectives of the CPCL by removing engineering responsibility from students. Therefore, if these particular subsystems can be designed, tested, and integrated in-house at Cal Poly, the result would be twofold: 1) the space of missions supportable by the CPCL under tight budget constraints will grow, and 2) students will be provided with unique, hands-on guidance, navigation, and control learning opportunities. In this thesis, the CPCL’s attitude determination and control system design and analysis toolkit is significantly improved to support in-house ADCS development. The toolkit—including the improvements presented in this work—is then used to complete the existing, partially complete CPCL ADCS design. To fill in missing gaps, particular emphasis is placed on guidance and control algorithm design and selection of attitude actuators. Simulation results show that the completed design is competitive for use in a large class of small satellite missions for which pointing accuracy requirements are on the order of a few degrees.
20
Brummitt, Marissa. "Development of CubeSat Vibration Testing Capabilities for the Naval Postgraduate School and Cal Poly San Luis Obispo." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/470.
Full textAbstract:
The Naval Postgraduate School is currently developing their first CubeSat, the Solar Cell Array Tester CubeSat, or NPS-SCAT. Launching a CubeSat, such as NPS-SCAT, requires environmental testing to ensure not only the success of the mission, but also the safety of other CubeSats housed in the same deployer. This thesis will address the development of CubeSat vibration testing methodology at NPS, including subsystem testing, engineering unit qualification, and flight unit testing. In addition, the new Cal Poly CubeSat Test POD Mk III will be introduced and evaluated based upon comparison with the Poly Picosatellite Orbital Deployer (P-POD). Using examples from the development of NPS-SCAT and test data from Cal Poly’s Test POD Mk III and P-POD, the current CubeSat testing methodology will be verified and an improved method for NPS CubeSat subsystem testing will be presented.
21
Bolstad, Anton Johan. "Development of a Patch Antenna Array between 2-6 GHz with Phase Steering Network for a Double CubeSat." Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9917.
Full textAbstract:
To make a double CubeSat with limited power resources capable of transmitting large amounts of data to Earth a high gain antenna is needed. In this thesis a switched beam MSA array operating at 5.84 GHz has been designed to operate on a double CubeSat. The array has 5 beams and uses a switched-line phase shifter to switch between beams. Three different array geometries has been proposed. Computer simulations suggest that the array should be capable of an effective beamwidth of over 60 degrees with a directivity of over 11 dBi. A feed network has been designed to fit the best suited geometry. A ground plane will separate the feed network from the antenna elements. Along with the full array solution all the sub parts has been realized as test circuits. This allows for an evaluation of their characteristics. A TRL calibration kit has also been designed so that the sub parts could be more accurately evaluated. When sending the circuits to fabrication it appeared to be a problem with the selected substrate used for the antenna elements. A redesign using the same substrate for the feed network and antennas was done and production commenced. As it turns out, the TRL calibration kit was not good enough so the S-parameters had to be measured with regular SOLT calibration. Significant problems with connection to ground and mismatches due to a poor SMA-to-microstrip transition was encountered. This caused large deviations between measured and simulated results. It was also discovered that the wrong dielectric constant had been used. This error caused the antenna elements to be dimensioned for operation at 5.70 GHz instead of 5.84 GHz. Problems was also encountered in the switched line phase shifter design. Beam-lead PIN-diodes has been used and due to their small size, a sufficient quality of the soldering was not achieved. This lead to different losses through the phase shifter which again caused the different beam directions to vary from simulations. Only one beam had characteristics similar to simulations. Measurements on the array without phase shifters showed good correspondence with simulation results (adjusted for the correct dielectric constant). It is concluded that by making a better SMA-to-microstrip transition, improve the soldering work and do a redesign with the correct dielectric constant, the array configuration should work as outlined in the design process.
22
Glassey, Kalia R. "Development of an Imager System Optimized for Low-Power, Limited-Bandwidth Space Applications." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/64.
Full textAbstract:
A relatively new picosatellite standard, CubeSats have traditionally been used for simple educational missions. As CubeSats become more complex and utilize more complex sensors such as imagers, they gain enhanced credibility as satellite platforms.
Imaging systems on CubeSats have the potential to be used for a variety of uses, such as earth and weather monitoring, attitude determination, and remote sensing. However the size and power limitations of CubeSats pose an interesting challenge to the design of a capable, robust imaging system.
This thesis outlines the objectives and requirements of CP-3’s imaging system, and describes the development process and methods. Test results from the imaging system are included, as well as lessons learned gleaned from CP-3’s on-orbit operations.
This document can serve as a guideline for other teams wishing to develop imaging systems. While other developers may have different requirements or constraints, this roadmap illustrates each of the many considerations that must be taken into account when designing an imaging system.
23
Ralph, Alyssa M. "Pathfinding Interplanetary Bus Capability for the Cal Poly CubeSat Laboratory Through the Development of a Phobos-Deimos Mission Concept." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2209.
Full textAbstract:
With the rise of CubeSats and the demonstration of their many space applications, there is interest in interplanetary CubeSats to act for example as scientific investigations or communications relays. In line with the increasing demand for this class of small satellites, the Cal Poly CubeSat Lab (CPCL) seeks to develop a bus that could support an interplanetary science payload. To facilitate this, a mission concept to conduct science of the moons of Mars, Phobos and Deimos, is investigated by determining the mission needs for a CubeSat in a Phobos-Deimos cycler orbit through the development of a baseline design to meet mission objectives. This baseline design is then compared by subsystem to CPCL’s current capabilities to identify technology, facility, and knowledge gaps and recommend a path forward to close them. The resulting baseline design is a 16U bus capable of transferring from an initial low Mars orbit to a Phobos-Deimos cycler orbit using a combined chemical and electric propulsion system. The bus is designed for a 3.5 year mission lifetime collecting radiation data and images, utilizing a relay architecture to downlink payload data. Estimates for mass, volume, and power available for an additional payload are up to 2.3 kg in ~4U with power consumption up to 13 to 38 W. This baseline requires further iteration due to non-closure of the thermal protection subsystem and improvement of other subsystems but serves as a starting point for exploration into CPCL’s next steps in becoming an interplanetary bus provider. Major subsystem areas identified for hardware performance improvement within CPCL are propulsion, communications, power, and mechanisms.
24
Wolosik, Anthony Thomas. "Advancements in the Design and Development of CubeSat Attitude Determination and Control Testing at the Virginia Tech Space Systems Simulation Laboratory." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/84980.
Full textAbstract:
Among the various challenges involved in the development of CubeSats lies the attitude determination and control of the satellite. The importance of a properly functioning attitude determination and control system (ADCS) on any satellite is vital to the satisfaction of its mission objectives. Due to this importance, three-axis attitude control simulators are commonly used to test and validate spacecraft attitude control systems before flight. However, these systems are generally too large to successfully test the attitude control systems on-board CubeSat-class satellites. Due to their low cost and rapid development time, CubeSats have become an increasingly popular platform used in the study of space science and engineering research. As an increasing number of universities and industries take part in this new approach to small-satellite development, the demand to properly test, verify, and validate their attitude control systems will continue to increase. An approach to CubeSat attitude determination and control simulation is in development at the Virginia Tech Space Systems Simulation Laboratory. The final test setup will consist of an air bearing platform placed inside a square Helmholtz cage. The Helmholtz cage will provide an adjustable magnetic field to simulate that of a low earth orbit (LEO), and the spherical air bearing will simulate the frictionless environment of space. In conjunction, the two simulators will provide an inexpensive and adjustable system for testing any current, and future, CubeSat ADCS prior to flight. Using commercial off the shelf (COTS) components, the Virginia Tech CubeSat Attitude Control Simulator (CSACS), which is a low cost, lightweight air bearing testing platform, will be coupled with a 1.5-m-long square Helmholtz cage design in order to provide a simulated LEO environment for CubeSat ADCS validation.Master of Science
25
Lindh, Marcus. "Development and Implementation of Star Tracker Electronics." Thesis, KTH, Rymd- och plasmafysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148955.
Full textAbstract:
Star trackers are essential instruments commonly used on satellites. They provide precise measurement of the orientation of a satellite and are part of the attitude control system. For cubesats star trackers need to be small, consume low power and preferably cheap to manufacture. In this thesis work the electronics for a miniature star tracker has been developed. A star detection algorithm has been implemented in hardware logic, tested and verified. A platform for continued work is presented and future improvements of the current implementation are discussed.Stjärnkameror är vanligt förekommande instrument på satelliter. De tillhandahåller information om satellitens orientering med mycket hög precision och är en viktig del i satellitens reglersystem. För kubsatelliter måste dessa vara små, strömsnåla och helst billiga att tillverka. I detta examensarbete har elektroniken för en sådan stjärnkamera utvecklats. En algoritm som detekterar stjärnor har implementerats i hårdvara, testats och verifierats. En hårdvaruplattform som fortsatt arbete kan utgå ifrån har skapats och förslag på förbättringar diskuteras.
26
Giesselmann, Jens Uwe Michael, and jens giesselmann@gmx net. "Development of an Active Magnetic Attitude Determination and Control System for Picosatellites on highly inclined circular Low Earth Orbits." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070514.162516.
Full textAbstract:
Small satellites are becoming increasingly important to the aerospace industry mainly due to their significantly reduced development and launch cost as well as shorter development time frames. In order to meet the requirements imposed by critically limited resources of very small satellites, e.g. picosatellites, innovative approaches have to be taken in the design of effective subsystem technologies. This thesis presents the design of an active attitude determination and control system for flight testing on-board the picosatellite 'Compass-1' of the University of Applied Sciences Aachen, Germany. The spacecraft of the CubeSat class with a net spacecraft mass of only 1kg uses magnetic coils as the only means of actuation in order to satisfy operational requirements imposed by its imagery payload placed on a circular and polar Low Earth Orbit. The control system is capable of autonomously dissipating the tumbling rates of the spacecraft after launch interface separ ation and aligning the boresight of the payload into the desired nadir direction within a pointing error of approximately 10°. This nadir-pointing control is achieved by a full-state feedback Linear Quadratic Regulator which drives the attitude quaternion and their respective rates of change into the desired reference. The state of the spacecraft is determined by a static statistical QUEST attitude estimator processing readings of a three-axis magnetometer and a set of five sun sensors. Linear Floquet theory is applied to quantify the stability of the controller and a non-linear dynamics simulation is used to confirm that the attitude asymptotically converges to the reference in the absence of environmental disturbances. In the presence of disturbances the system under control suffers from fundamental underactuaction typical for purely magnetic attitude control but maintains satisfactory alignment accuracies within operational boundaries.
27
Staniscia, Giada. "Development of a Low Earth Orbit Mission Preliminary Analysis Tool." Thesis, KTH, Rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-265613.
Full textAbstract:
The objective of this project is the development of a mission analysis tool for the nanosatellite company GomSpace Sweden. Although there are many existing software, they can be quite complicated and time consuming to use. The goal of this work is to build a simple app to be used at the earliest stages of space missions in order to obtain key figures of merit quickly and easily. By comparing results, assessing the feasibility of customer needs, analysing how various parameters affect each other, it enables immediate deeper understanding of the implications of the main design decisions that are taken at the very beginning of a mission. The tool shall aid the system engineering process of determining orbit manoeuvre capability specifically for CubeSat electric propulsion systems taking into account the most relevant factors for perturbation in Low Earth Orbit (LEO), i.e. atmospheric drag and Earth’s oblateness effects. The manoeuvres investigated are: orbit raising from an insert orbit to an operating orbit, orbit maintenance, deorbiting within the space debris mitigation guidelines and collision avoidance within the 12 to 24 hours that the system has to react. The manoeuvres cost is assessed in terms of Delta v requirements, propellant mass and transfer times. The tool was developed with MATLAB and packaged as a standalone Linux application.Målet med detta examensarbete var att utveckla ett verktyg för missionsanalys för nanosatellitföretaget GomSpace Sweden. Det finns många andra mjukvaror för att nå samma mål men de är ofta komplicerade och tidskrävande. Det specifika målet var således att skapa en enkel applikation som kan användas i de tidiga stegen av utformning av rymduppdrag för att snabbt och enkelt få fram viktiga parametrar. Genom att jämföra resultat, uppskatta genomförbarheten av kundbehov och analysera hur olika parametrar påverkar varandra kan omedelbar förståelse erhållas rörande påverkan av designbeslut som tas i början av rymduppdragen. Verktyget ska stödja systemingenjörsprocessen genom att uppskatta banförflyttningskapacitet för elektriska framdrivningssystem för CubeSats och ta i beaktande de mest relevanta faktorerna gällande störningar i låg jordbana (LEO), i.e. atmosfäriskt motstånd och effekterna av Jordens form. De undersökta manövrarna är: banhöjning från injektionsbana till operationell bana, banunderhåll, bansänkning som följer riktlinjerna för rymdskrot och kollisionsundvikande inom de 12 till 24 timmar som systemet har på sig att reagera. Kostnaden för manövrarna är uppskattade genom DeltaV-krav, massan av bränslet och förflyttningstider. Verktyget utvecklades med MATLAB och paketerades som en fristående applikation i Linux.
28
Dauner, Johannes. "Further Development of a Distributed Robust Control Approach towards a Nanosatellite Formation Flying Application." Thesis, Luleå tekniska universitet, Rymdteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-80047.
Full textAbstract:
This thesis proposes a distributed robust control approach for low-thrust nanosatellite formation flying. The presented control approach is the further development of an already existing approach which combines robust control and distributed control using the consensus approach. The adjustments presented in this thesis are intended to enable the usage of the control approach in nanosatellite missions such as the upcoming NetSat mission. Stability criteria, optimization goals and constraints such as the limited maximum thrust are formulated with the help of Linear Matrix Inequalities (LMIs). In addition, the presented control approach includes methods for exploiting the maximum thrust and for collision avoidance. Due to the design as a distributed controller based on the consensus approach, a satellite formation can be maintained even in the case of the failure of the propulsion system and/or Attitude Determination and Control System (ADCS) of a single satellite. To verify the design of the control approach, simulations of the formation scenarios planned for the NetSat mission are performed with a satellite formation simulation framework based on Orekit and MATLAB®.
29
Biddy, Christopher Lorian. "Development of a High Performance Micropropulsion System for CubeSats." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/150.
Full textAbstract:
Picosatellites are defined as satellites with a mass between 0.1 and 1kg (Miniaturized satellite). Picosatellites are typically designed to work together or function in formations (Miniaturized satellite). A specific type of Picosatellite known as CubeSats were introduced in 1999 and since then have increased in popularity so that there are now over 80 CubeSat programs around the world. CubeSats are defined as cubic units 10cm on each side and no more than 1kg in mass. CubeSats are required to conform to the CubeSat Standard created by California Polytechnic State University and Stanford University and be compatible with Cal Poly’s P-POD deployment system (Toorian, 2005). Some CubeSat uses include earth imaging, communications projects and various scientific experiments. CubeSats currently require attitude control and in the future, may require, maintaining a specific orbit, or changing orbit. With this ability many new activities may be possible for CubeSats. These activities could include rendezvous, vehicle inspection, formation flying and de-orbiting. For these activities to be possible, a high performance propulsion system is required. The goal of this thesis is to design and test an affordable, safe, and effective micro-propulsion system for CubeSats.
30
Hemberg, Alexander. "Automated booking and scheduling for CubeSats : Development of an automated Scheduling engine for satellite communication with emphasis on communication with CubeSats." Thesis, KTH, Rymd- och plasmafysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160615.
Full textAbstract:
This thesis work details the development of an automatic scheduling engine for satellite communication from the operational stand point of a ground station. The aim has been to create a scheduling engine that autonomously calculates passes for a large number of satellites over a ground station and assigns these passes to appropriate resources. The process used can be described as rule based scheduling, where each satellite is assigned a set of specic requirements that the scheduler tries to satisfy in order to create a schedule that satises all specied requirements. This approach is in contrast to the most commonly used scheduling today, where satellite operators request passes and ground stations try to satisfy these requests, often manually. With rule based scheduling satellite operators are instead allowed to set requirements and the pass times are chosen automatically so as to optimize the process and admit a higher utilization of available resources. It is shown that a typical utilization of a ground stations resources of about 60% can be achieved. In addition to the scheduling engine a simple web interface has been developed, allowing the control of all parameters and scheduling through a web browser, thus demonstrating the ability to make this system more widely accessible for a broader range of users. The development of a rule based scheduler illustrates the possibility of making the process of satellite to ground communications more streamlined from the part of the ground station while at the same time permitting an increase in the number of passes it can support.Det har examensarbetet beskriver utvecklingen av en autonom schemalaggare for satellitkommunikation fran en markstations perspektiv. Syftet har varit att skapa en autonom schemalaggare som pa egen hand beraknar passtider for ett stort antal satelliter over en markstation och schemalagger dessa pass pa lampliga resurser. Processen som anvands kan beskrivas som regelbaserad schemalaggning, dar varje satellit som ska schemalaggas tilldelas ett antal specika krav som schemalaggaren sedan forsoker tillfredsstalla for att pa sa satt skapa ett schema som tillfredsstaller alla krav fran alla satellitoperatorer. Det har angreppssattet skiljer sig fran det som anvands mest idag, dar satellitoperatorer staller detaljerade krav pa vilka pass som ska bokas in hos markstationen, och personalen pa markstationen forsoker att tillfredsstalla dessa krav sa langt det ar mojligt, ibland manuellt. Med regelbaserad schemalaggning far satellitoperatorer istallet specicera ett set med krav for sina satelliter, och schemalaggaren valjer passtider sa att alla krav for alla satelliter tillgodoses pa ett sa eektivt satt som mojligt, sa att en hogre belaggning pa markstationen kan uppnas an vad som annars vore mojligt. Det visas i dokumentet att en belaggning pa ca 60 % ar mojlig med hjalp av regelbaserad schemalaggning; hogre an normalscenariot for en markstation idag. Utover schemalaggaren har ett webbaserat granssnitt utvecklats som mojliggor kontroll av satellitparametrar och schemalaggning via en webblasare. Pa sa satt visas mojligheten att gora ett sadant har system tillgangligt for ett brett spektrum av anvandare. Utvecklingen av en automatiserad schemalaggare illustrerar mojligheten att forenkla processen for passbokning av satellit till markstationskommunikation samtidigt som en forhallandevis hog belaggning kan uppnas.
31
Driver, Nicole Andrea. "Assessment and development of de-orbiting technology for nanosatellites." Thesis, Cape Peninsula University of Technology, 2019. http://hdl.handle.net/20.500.11838/3112.
Full textAbstract:
Thesis (MEng (Mechanical Engineering))--Cape Peninsula University of Technology, 2019The accumulating space debris has been a developing problem for many years. Technological advances led to the creation of nanosatellites, which allows more affordable access to space. As a result, the number of satellite launches is rapidly increasing, which, translates into an increase in debris in the low earth orbit (LEO) and geostationary orbit (GEO). To comply with the Inter-Agency Space Debris Coordination Committee (IADC) requirement of a 25-year maximum orbital lifetime, nanosatellites must have an end of life strategy. Failure to meet these guidelines may not only cause catastrophic collisions but may make future space travel even more challenging. Consequently, orbital lifetime predictions must be completed for nanosatellites. Considering this, the aim of this thesis is to investigate the orbital lifetime predictions for the nanosatellite ZACube-2, and the effects on the orbital lifetime if ZACube-2 is fitted with deorbiting technology, specifically a drag argumentation device. An in-depth literature review regarding the current state of technology pertaining to nanosatellite de-orbiting was conducted. This was followed by studies regarding orbital dynamics and perturbation forces. Four case studies were simulated in NASA’s Debris assessment software (DAS 2.0) using orbital parameters extracted from the two-line element (TLE) file. General information such as launch date and final mass was provided by F’SATI. The Baseline case study presented the orbital lifetime of ZACube-2, without any drag enhancement device. This was followed by case study 1,2 and 3 which represented ZACube-2 when fitted with three different drag enhancement devices. A comparison study indicated a reduction in all three cases. A new inflatable cube de-orbiting device (ICDD) concept was also presented, and the effects it has on the orbital lifetime predictions are showcased in case study three. Two deployment concepts were considered and evaluated against design requirements. Solidworks software was used to model the most suitable concept as well as perform finite element analysis on the structure. Static analysis was followed by natural frequency analysis in which the natural frequencies of the components and assembled structure were extracted. The Soyuz launch vehicle’s sinusoidal testing requirements were used to evaluate the structures survivability under dynamic loading. Based on the finite element , and harmonic analysis it was concluded that the structures will survive the launch conditions of the Soyuz launch vehicle. Furthermore, individual parameters affecting orbital lifetime predictions are also identified, in the form of a mass and cross-sectional sensitivity study and a ballistic coefficient versus orbital time study.
32
Tshilande, Thinawanga. "Development of real-time orbital propagator software for a Cubesat's on-board computer." Thesis, Cape Peninsula University of Technology, 2015. http://hdl.handle.net/20.500.11838/2196.
Full textAbstract:
Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2015.A precise orbit propagator was developed for implementing on a CubeSat's on-board computer for real-time orbital position and velocity determination and prediction. Knowledge of the accurate orbital position and velocity of a Low Earth Orbit (LEO) Cubesat is required for various applications such as antenna and imager pointing. Satellite motion is governed by a number of forces other than Earth's gravity alone. The inclusion of perturbation forces such as Earth's aspheric gravity, third body attraction (e.g. Moon and Sun), atmospheric drag and solar radiation pressure, is subsequently required to improve the accuracy of an orbit propagator. Precise orbit propagation is achieved by numerically integrating a set of coupled second order differential equations derived from satellite's perturbed equations of motion. For the purpose of this study two numerical integrators were selected: RK4 - Fourth order Runge Kutta method and RKF78 - results from embedding RK7 into RK8. The former is a single-step integrator while the latter is a multi-step integrator. These integrators were selected for their stability, high accuracy and computational efficiency. An orbit propagation software tool is presented in this study. Considering the processing power of Central Processing Unit (CPU) of CubeSat's on-board computer and a trade-off between precision and computational cost, the 10 x 10 and 20 x 20 gravity field models, the Exponential atmospheric model and Jacchia 70 static atmospheric model, were implemented. A 60 x 60 gravity field model is also investigated for reference. For validation purpose the developed software tool results were compared with results from Systems Tool Kit (STK) and Satellite Laser Ranging (SLR) using SUNSAT satellite reference orbit.
National Research Foundation
33
Mannes, Quentin. "ICE Cubes Mission: Design, Development and Documentation of the Cube-Zero System." Thesis, Luleå tekniska universitet, Rymdteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65732.
Full textAbstract:
The International Space Station provides a high-quality of microgravity and extended exposure time which makes it a platform of choice for microgravity research. In order to increase accessibility of onboard experimentation, Space Applications Services will soon launch the ICE Cubes facility as part of its ICE Cubes Service. The facility is foreseen to host standardized plug-and-play payload cubes to reduce overall cost and procedure time required to install payloads on the station. To remotely support the facility it is decided to develop a utility cube named Cube-Zero that will be launched and installed with the facility on the station. This thesis work included the complete design, development and documentation of the cube. The thesis started by conducting a preliminary needs and market study from which two specific purposes were defined for the cube. In addition to its original function of support-utility, the cube is tasked to be a technical commercial demonstrator for the service. This led to the conceptual design of the cube as a multidisciplinary framework able to host two user-defined experiment modules. The preliminary concept was further refined in this paper and with support of prototypes, simulations and analyses led to a final functional design for the Cube-Zero. The work is concluded with the manufacturing of an engineering model of the cube. The model is fully operational, can support the test of the facility before launch and can demonstrate to users its versatility and ease of use in operating any kind of experiment module. Eventually, the information gathered in this thesis report will support future users into developing their own Cube-Zero payload module and guide Space Applications Services into manufacturing, testing and operating the Cube-Zero protoflight model.ICE Cubes
34
Saltin, Joakim. "Interactive visualization of financial data : Development of a visual data mining tool." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-181225.
Full textAbstract:
In this project, a prototype visual data mining tool was developed, allowing users to interactively investigate large multi-dimensional datasets visually (using 2D visualization techniques) using so called drill-down, roll-up and slicing operations. The project included all steps of the development, from writing specifications and designing the program to implementing and evaluating it. Using ideas from data warehousing, custom methods for storing pre-computed aggregations of data (commonly referred to as materialized views) and retrieving data from these were developed and implemented in order to achieve higher performance on large datasets. View materialization enables the program to easily fetch or calculate a view using other views, something which can yield significant performance gains if view sizes are much smaller than the underlying raw dataset. The choice of which views to materialize was done in an automated manner using a well-known algorithm - the greedy algorithm for view materialization - which selects the fraction of all possible views that is likely (but not guaranteed) to yield the best performance gain. The use of materialized views was shown to have good potential to increase performance for large datasets, with an average speedup (compared to on-the-fly queries) between 20 and 70 for a test dataset containing 500~000 rows. The end result was a program combining flexibility with good performance, which was also reflected by good scores in a user-acceptance test, with participants from the company where this project was carried out.
35
Pietzka, Mathias [Verfasser], Jochen [Akademischer Betreuer] [Gutachter] Schein, and Michael [Gutachter] Keidar. "Development and Characterization of a Propulsion System for CubeSats based on Vacuum Arc Thrusters / Mathias Pietzka ; Gutachter: Jochen Schein, Michael Keidar ; Akademischer Betreuer: Jochen Schein ; Universität der Bundeswehr München, Fakultät für Elektrotechnik und Informationstechnik." Neubiberg : Universitätsbibliothek der Universität der Bundeswehr München, 2016. http://d-nb.info/1115728423/34.
Full text
36
Pietzka, Mathias Verfasser], Jochen [Akademischer Betreuer] [Schein, and Michael [Gutachter] Keidar. "Development and Characterization of a Propulsion System for CubeSats based on Vacuum Arc Thrusters / Mathias Pietzka ; Gutachter: Jochen Schein, Michael Keidar ; Akademischer Betreuer: Jochen Schein ; Universität der Bundeswehr München, Fakultät für Elektrotechnik und Informationstechnik." Neubiberg : Universitätsbibliothek der Universität der Bundeswehr München, 2016. http://d-nb.info/1115728423/34.
Full text
37
Swarts, Kevin Michael. "Development of a stock cube with functional food characteristics." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/765.
Full textAbstract:
Thesis submitted in fulfilment of the requirements for the degree
Master of Technology: Consumer Science: Food and Nutrition
in the Faculty of Applied Sciences
at the Cape Peninsula University of Technology
2012The chronic diseases of lifestyle, tuberculosis and Human immunodeficiency virus/Acquired immunodeficiency syndrome have a high prevalence in South Africa. These diseases are characterised by oxidative stress and a chronic inflammatory state that contribute to both the development and the acceleration of these diseases. Research into the phytochemical plant food components suggest that these substances could possibly play a vital role in the prevention of such disease. Corn steep liquor (CSL) is a waste product with an exceptionally high polyphenol content and total antioxidant capacity (TAC). This led to the suggestion that it could be utilised in the development of food products with functional food characteristics. Stock cubes, due to the widespread use among consumers of different socio-economic backgrounds, were identified as vehicle for the delivery of the CSL with its phytochemical content. This lead to the development of a stock cube utilising CSL as a source of phytochemical polyphenolic antioxidants with the micronutrients zinc, selenium and copper as added support to immunonutrition, along with iron due to the wide spread prevalence of iron deficiency in the South African population. The acceptability of the developed stock cube was tested by preparing savoury rice and pea soup and having blue collar (n = 50) and white collar (n = 49) participants rate the acceptability on a 9-point hedonic scale, ranging from “dislike extremely” to “like extremely”. The savoury rice received a 41% “like very much” rating followed by a 24% “like moderately” rating. The pea soup was rated even more positively as it received a 42% “like very much” rating and a 29% “like extremely” rating. In addition, among the blue collar participants, significant (p < 0.05 for each) findings occurred with a greater liking of the sample dishes prepared with the developed stock cube by participants of the ethnic Black grouping, with Xhosa as home language and being married, as well as those participants who habitually prepare the meals in the household. A significant (p < 0.05) finding with the white collar participants was a greater liking of the sample dishes prepared with the developed stock cube among those participants who would be willing to make use of a stock cube with health benefits. The developed stock cube was also subjected to six months accelerated shelf-life stability testing, reflecting twelve months real time storage. The parameters measured were microbial growth, oxidative rancidity, antioxidant status and organoleptic changes. All microbial growths tested remained within the acceptable specification ranges. Oxidative rancidity, measured as the peroxide value, was detected analytically at the fifth and sixth samplings, but was not detectable organoleptically. The antioxidant status, measured as the TAC and the total polyphenol content, remained relatively stable during the testing period. Though no noticeable organoleptic changes were observed during the stability testing, there was a darkening of the colour by the second sampling. The results of the acceptance testing, as well as the shelf-life stability testing, support the conclusions that the study objectives of developing a stock cube with functional food characteristics and it being received positively by consumers were achieved. Keywords: stock cubes; corn steep liquor; phytochemicals; consumer acceptance; new product development
38
Cakmak, Mehtap. "Development Of A Multigrid Accelerated Euler Solver On Adaptively Refined Two- And Three-dimensional Cartesian Grids." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610753/index.pdf.
Full textAbstract:
Cartesian grids offer a valuable option to simulate aerodynamic flows around complex geometries such as multi-element airfoils, aircrafts, and rockets. Therefore, an adaptively-refined Cartesian grid generator and Euler solver are developed. For the mesh generation part of the algorithm, dynamic data structures are used to determine connectivity information between cells and uniform mesh is created in the domain. Marching squares and cubes algorithms are used to form interfaces of cut and split cells. Geometry-based cell adaptation is applied in the mesh generation. After obtaining appropriate mesh around input geometry, the solution is obtained using either flux vector splitting method or Roe&rsquos approximate Riemann solver with cell-centered approach. Least squares reconstruction of flow variables within the cell is used to determine high gradient regions of flow. Solution based adaptation method is then applied to current mesh in order to refine these regions and also coarsened regions where unnecessary small cells exist. Multistage time stepping is used with local time steps to increase the convergence rate. Also FAS multigrid technique is used in order to increase the convergence rate. It is obvious that implementation of geometry and solution based adaptations are easier for Cartesian meshes than other types of meshes. Besides, presented numerical results show the accuracy and efficiency of the algorithm by especially using geometry and solution based adaptation. Finally, Euler solutions of Cartesian grids around airfoils, projectiles and wings are compared with the experimental and numerical data available in the literature and accuracy and efficiency of the solver are verified.
39
Chiang, Jen-Hong, and 江仁宏. "Development of the CubeSat RF Communications Systems." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/j79qyv.
Full textAbstract:
碩士國立中央大學
光機電工程研究所
102
In this paper, in order to achieve CubeSat RF communication system as the goal. The CubeSat RF module specifications as the references. Using UHF 433MHz frequency as the primary communications and overall system modularity. This paper through the system specifications. Design RF system automatically packet and unpacks the data. Design the command protocol. Planning hardware configuration, function block diagram, state machine and actual implementation the system. Finally, the system performance test. Verify that the system functions. Also tested communications capabilities. And from which to discuss ways to improve the shortcomings.
40
HUANG, CHUNG-CHENG, and 黃崇誠. "Development of power management and supply system of CubeSat." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/b8d7vc.
Full textAbstract:
碩士國立中央大學
光機電工程研究所
102
The study design of a complete power management and supply system for cubic satellite , using secondary lithium batteries and super capacitor as a power storage element in the satellites, and with the use of solar power charging module supplement provides cubic satellite computer and scientific payload set the required power use, and with input overvoltage protection and overload protection to prevent accidental damage to the system, and equip the communication interface for controlling of each power channel . After completing the circuit and mechanism design, functionality and performance of the power system is also be verified.
41
Chen, Yi-Kai, and 陳義凱. "Development of a Test Platform for Cubesat Sun Sensors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/46d3cn.
Full textAbstract:
碩士國立虎尾科技大學
飛機工程系航空與電子科技碩士班
106
Sun sensors are one of the most popular instruments for attitude determination in the attitude control systems of satellites. Sun sensors are used to find the sun vector with respect to the satellite and to estimate the attitude of satellite by the given installation positions of sun sensors. This thesis describes the establishment of a platform for performance evaluation of sun sensors in a Cubesat. Due to the constraints of the budget, space, power and weight, a sun sensor designed based on multiple digital light sensors is proposed in this thesis. To verify the feasibility and functions of the proposed sun sensor system, a measurement platform is established. Then the proper installation place of sun sensors can be selected. This platform mainly includes a rotational motion platform and a set of wireless data acquisition system. The platform has controllable speed and position. A mockup of satellite is built with proper placement of sun sensors. This platform can perform the rotational speed control and collect the data from sun sensors.
42
Cardoso, Nuno Filipe Sousa. "Development of an ARGOS beacon for the VORSat Cubesat." Dissertação, 2012. http://hdl.handle.net/10216/63331.
Full text
43
Ye, Cheng-Wei, and 葉丞偉. "UHF/VHF dual band transceiver development platforms for CubeSat." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/393q3k.
Full textAbstract:
碩士國立中央大學
光機電工程研究所
107
In this paper, we focus on development of half-duplex dual band radio module for CubeSat, support 144-146MHz and 435-438MHz radio band. The system is designed and implemented from COTS, Commercial Off-The-Shelf, component, which specification follows the mainstream amateur packet radio protocol. With research the specification requirements of communication system, we design the hardware of radio and base band system, including microcontroller, RF modulation chip, low noise amplifier and power amplifier. Then we analyze and calculate the theoretical performance of each subsystem and the whole system, which is for reference of subsequent verification. In the end of paper, we verify the performance of subsystem and the overall transmission performance. Prove that the transceiver system can be achieved at BER of 〖10〗^(-4) with a signal strength 118dBm. In addition, the signal transmitted by the ground station with EIRP of 50dBm is received. The maximum communication distance of UHF and VHF are 6913 km and 19977 km respectively.
44
Cardoso, Nuno Filipe Sousa. "Development of an ARGOS beacon for the VORSat Cubesat." Master's thesis, 2012. http://hdl.handle.net/10216/63331.
Full text
45
Panagopoulos, Jorge Antunes. "Development of a CubeSat power management subsystem for the ALSat#1 Mission." Master's thesis, 2020. http://hdl.handle.net/10400.6/10624.
Full textAbstract:
This thesis aims to develop and analyse the power management subsystem for the ALSat#1
mission that studies the cosmic rays in low earth orbit. The primary task is to find components
to build and make the CubeSat able to do the mission and subsequently analyse if it is capable
to make the mission in three different orbits RAANs (RAAN 0º; RAAN 53.5º; RAAN 90º) with
different eclipse times.
This was done by using a MATLAB programme to analyse the energy consumed and energy deficit
during an orbit and during a day.
It was found out that the options orbit with RAAN 0º and orbit with RAAN 53.5º can complete
the mission without change. However, the orbit with RAAN 90º has some deficit cumulated after
a day which leads to energy insufficiency, and is only possible to overcame it with some changes
in the algorithm or in the components used.Esta tese tem como objetivo desenvolver e analisar o subsistema de gerenciamento de energia da missão ALSat # 1 que pretende estudar os raios cósmicos em órbita terrestre baixa. A tarefa principal é encontrar componentes para construir e tornar o CubeSat capaz de realizar a missão e, posteriormente, analisar sua capacidade de realizar a missão em três RAANs de órbita diferentes (RAAN 0º; RAAN 53,5º; RAAN 90º) com diferentes tempos de eclipse. O estudo foi feito usando um programa MATLAB para analisar a energia consumida e o déficit de energia durante uma órbita e durante um dia. Verificou-se que as órbitas com RAAN 0º e RAAN 53,5º podem completar a missão sem alterações. Porém, a órbita com RAAN 90º tem algum déficit acumulado após um dia que leva a insuficiência energética, a qual só é possível superá-la com algumas mudanças no algoritmo ou nos componentes usados.
46
Ming-XianHuang and 黃銘賢. "Development of Flight Software and Implementation of Test Bed for the IRIS Cubesat." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/4z2h8t.
Full textAbstract:
碩士國立成功大學
電機工程學系
107
Intelligent Remote-Sensing and Internet Satellite (IRIS) is a Cubesat project in which two nanosatellites IRIS-A and IRIS-B are being developed by National Cheng Kung Universit. IRIS-A, it is a 2U Cubesat and equipped with an Internet of Things (IoTs) payload to achieve the Doppler shift estimation and improve the quality of downlink signal. IRIS-B, it is a 3U Cubesat equipped with a Remote-Sensing Instrument (RSI) to carry out image capturing and conduct object detection and disaster prediction via an uploaded training model from deep learning. During the mission process, flight software (FSW) is a critical part of the function, which serves as a core of management in the satellite. The proposed FSW and its functions are implemented in the Onboard Computer (OBC) of the IRIS Cubesat. In the IRIS project, in which there are two payloads with entirely different purposes and interfaces, so a flexible FSW needs to be developed. FSW is responsible for system maintenance, validation, and execution of telecommand (TC), data flow handling between modules and operation of mission scheduling. OBC provides the hardware interface to communicate with subsystems and payload. The thesis intends to discuss the implementation of a reliable and flexible FSW framework to serve various payloads, which is to reduce development cycle. The content includes software design and architecture of FSW, the transition of operation mode, anomaly handling, redundant storage. Moreover, for the success of the mission, the verification activities of FSW are also required. In this thesis, to make each test case flexible and easy to configure, a software test bed (STB) is developed, which simulates the behavior of subsystems. Moreover, in the thesis, two kinds of test scenarios are proposed, low-level test and ground based software test.
47
Martínez, Edgard. "Development of models for Attitude Determination and Control System components for CubeSat applications." Thesis, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65721.
Full textAbstract:
In this Master Thesis, numerical models of ADCS components are performed. The models will be used in the design of the first 3U CubeSat of the CSU Montpellier, the ROBUSTA 3-A. The goal of the thesis is to develop numerical models of angular rate sensors and reaction wheels and to obtain relevant information of these components in the context of the R-3A mission. Firstly, the state-of-the-art of models are outlined, and the most suitable are chosen. Secondly, assumptions are made, and the models are implemented. Next, the models are parametrized for specific elements to be used on R-3A. Lastly, the models are validated and simulated. The results of simulations confirm a choice of the CoTS components for the R3A mission. Besides, the results provide information about system performance parameters such as RW acceleration time, maximum satellite speed, and attitude knowledge accuracy in eclipse.
48
Joplin, Andrew Jonathan. "Development and testing of a miniaturized, dual-frequency, software-defined gps receiver for space applications." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-12-4842.
Full textAbstract:
While dual-frequency GPS receivers have been used in space for more than two decades, the size, power, and cost of this technology is an important driver for future space missions. The growing availability of launch opportunities for very small satellites known as nanosatellites and CubeSats raises the possibility of more affordable access to space measurements if the observation quality is sufficient to support the user's needs.
This thesis presents the initial development and testing of the Fast, Orbital, TEC, Observables, and Navigation (FOTON) receiver: a small, reconfigurable, dual-frequency, space-based GPS receiver. Originally developed as a science-grade software receiver for monitoring ionospheric scintillation and total electron content (TEC), this receiver was designed to provide high-quality GPS signal observations. The original receiver hardware was miniaturized and the software has been adapted for low earth orbit (LEO) operations. FOTON now fits within a 0.5U CubeSat form factor (8.3 x 9.6 x 3.8 cm), weighs 326 g, and consumes 4.5 W of instantaneous power, which can be reduced to <1 W orbit average power with on-off duty cycling. The receiver has been designed with commercial parts to keep manufacturing costs low.
Significant testing of FOTON has been performed with live signals and with signals generated by a Spirent GPS signal simulator. Initial terrestrial tests demonstrate behavioral consistency with the original heritage high-performance receiver. Several LEO simulations are presented, demonstrating FOTON's single-frequency and dual-frequency-enhanced positioning down to 0.5 m and 1.5 m, respectively, which can be improved using Kalman filter based POD. FOTON's potential for GPS radio occultation observation is also demonstrated. In addition, its acquisition and reacquisition performance is presented; on average, FOTON's time to first fix is approximately 45 seconds. Finally, navigation in geostationary orbit (GEO), a challenging application for space-based GPS receivers, is demonstrated. Extensive testing demonstrates that FOTON is a robust, versatile, high-precision dual-frequency space receiver. Its low cost, size, weight, and power requirements are key enablers for future small-satellite missions.text
49
Yi-ChenWang and 王翊臻. "Development of the floating Langmuir probe for cubesats." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/u23ybw.
Full textAbstract:
碩士國立成功大學
太空與電漿科學研究所
107
In recent years, the small-scale variation of the ionosphere and the re-entry process greatly draw scientists attentions. The plasma density of ionosphere in the region below 300 km varies dramatically, and electrons interact with ions frequently, the conventional Langmuir probe is not applicability of the research in this region due to its low temporal resolution. In this work, an innovated approach of the electron temperature (Te) and density (ne) measurements by an electrically floated circuit based on the principles of the double and triple Langmuir probes, named as the floating Langmuir probe (fLP), is presented. Hence, the goal of this work is to advance the a new measurement instrument based on the conventional Langmuir probe and make it suitable for cubesats to measure the plasma in the ionosphere and the atmospheric re-entry process. Comparing with the conventional Langmuir probe, fLP is designed as an electrically floating system, therefore it can measure the plasma on-board a cubesat stably with a high temporal resolution to measure the highly variating plasma during the atmospheric re-entry process. In this work, the design concept, performance analysis by simulation, hardware development and in-lab experiments of the fLP are presented. The electron temperature and density measured by the fLP at a well-floated system is verified by a well-grounded conventional Langmuir probe in the Space Plasma Operation Chamber owned by NCKU. It is demonstrated that the fLP neither influenced nor was influenced by the satellite potential variations. This instrument is capable of not only ionospheric plasma exploration, but also for the high-temperature and high-density plasma investigations around the spacecraft during its re-entry processes.
50
Lopes, Susana Fernandes. "Development of a low-cost Star Trackers for CubeSats." Master's thesis, 2019. http://hdl.handle.net/10451/38246.
Full textAbstract:
Tese de mestrado integrado, Engenharia Física, Universidade de Lisboa, Faculdade de Ciências, 2019A presente dissertação de mestrado foi desenvolvida em parceria com a empresa Omnidea, Lda e tem como principal objectivos desenvolver e testar um protótipo de desenvolvimento de um star tracker de baixo custo para ser implementado em missões cubeSat. Um star tracker é um instrumento que permite extrair a atitude de um satélite, ou seja, a direcção para a qual este está a apontar. O star tracker é actualmente o sensor mais caro e mais exacto para extracção da atitude e o seu funcionamento assemelha-se ao de uma câmara digital. A determinação de atitude com um star tracker inicia-se quando uma imagem das estrelas no campo de visão do sensor de imagem é extraída. Posteriormente, um algoritmo identifica as estrelas com base nas distâncias relativas entre estrelas vizinhas e calcula a atitude. Este processo é extremamente rápido, não durando mais do que fracções de segundo. Dada a expansão actual do mercado dos satélites inferiores a 100Kg, e em específico dos cubeSats, é de alta prioridade construir um star tracker que possa ser usado em missões de baixo custo desenvolvidas por pequenas empresas e universidades. Na presente dissertação é apresentada uma revisão do estado de arte de sensores de controlo de atitude para satélites, de forma a definir os requisitos pretendidos para o protótipo de desenvolvimento do star tracker. Com base na revisão feita, foi escolhido um sensor de imagem CMOS monocromático de 10MP fabricado pela Aptina (actual On-Semiconductor), juntamente com um sistema de lentes de baixo custo com um f-number de 1.6 e 35mm de distância focal. O sistema final tem um campo de visão de cerca de 10º. A carta electrónica associada ao sensor de imagem faz interface com um driver (ArduCAM USB camera shield), que permite a sua fácil implementação. Com o ArduCAM USB camera shield, o sensor de imagem pode ser manipulado através de ligação USB com um computador portátil ou computadores embebidos como o Beaglebone ou o Raspberry Pi. De forma a entender os limites de funcionamento do sensor para a sua aplicação enquanto star tracker, foi feita uma caracterização do seu ruído e um estudo teórico de fotometria estrelar. O algoritmo seleccionado para identificação das estrelas é o Tetra, que é um recente algoritmo desenvolvido por dois estudantes da universidade do MIT, nos Estados Unidos. Este algoritmo tem como base de funcionamento o algoritmo utilizado pelo Astrometry.net, uma ferramenta online de indentificação de corpos celestes. O algoritmo tetra utiliza como base de dados um catálogo com 9100 estrelas. De forma a testar o seu funcionamento com um catálogo mais amplo e recente (Hipparcos), com mais de 118218 estrelas, foram feitas alterações ao código do algoritmo Tetra. A performance do star tracker é testada com ambas as versões do algoritmo para diversas imagens. Numa fase final, o sensor de imagem e sistema de lentes foram ligados a um computador embebido Raspberry Pi. Um programa que une o código de funcionamento da ArduCAM USB camera shield ao algoritmo Tetra permite que o star tracker funcione de forma autónoma, através do envio de comandos de um portátil para o Raspberry Pi via Wi-Fi. Uma caixa de protecção e suporte ao sensor de imagem e à board ArduCAM USB camera shield foi desenvolvido na fresadora manual da faculdade, de forma a garantir a protecção dos componentes electrónicos mediante exposição ao ambiente exterior. O star tracker foi testado em ambiente nocturno, o mais longe possível de poluição luminosa, de forma a comprovar o seu funcionamento e estudar a sua performance.
This master thesis was developed in partnership with Omnidea, Lda. The main goal of this work is to develop (design and test) a prototype of a low cost star tracker for cubeSat missions. A star tracker is an instrument that can be assembled in satellites and allows to extract their attitude. The attitude is defined as the direction the cubeSat is pointing, with respect to a reference. The determination of a satellite’s attitude is made using the stars present in the field of view of the star tracker. An algorithm identifies stars by comparing the distance between neighbor stars with an internal catalog and computes attitude. The star tracker is currently the most expensive and accurate type of sensor for attitude determination. Since the cubeSats market has been evolving exponentially in the past years, it became high priority and mandatory to develop a star tracker that can be used in low cost missions developed by small companies and universities. In this thesis a literature research about attitude determinations sensors was made. From this review, the star tracker’s requirements were defined. Based on the requirements, the main parts chosen for the star tracker prototype to be developed consisted on a 10MP monochromatic CMOS image sensor from Aptina (actual On-Semiconductor), along with a low-cost lens system with a f-number of 1.6 and 35mm of focal distance. Considering the lens system’s focal length and the sensor’s size, the final system has an approximated field of view of 10_. The image sensor’s board is connected to a driver (ArduCAM USB camera shield), that allows its easy implementation. The image sensor can be controlled through an USB connection to a laptop, Beaglebone or Raspberry Pi. At this point, a theoretical study of stellar photometry is made, along with an experimental study of the image sensor’s noise. Both studies complement each other and allow to understand how the sensor behaves as a star tracker. The selected algorithm to star identification is Tetra, a recent algorithm developed by two MIT students in the United states. This algorithm uses an internal catalog of 9100 stars. In order to test the code with a more extended and recent catalog (Hipparcos), with about 118218 stars, alterations were made in the original Tetra algorithm. Both versions of the algorithm are tested with several images in a way to study their performance. In a final phase, the image sensor and lens system are finally implemented in Raspberry Pi. A program that links the ArduCAM USB camera shield’s code and Tetra algorithm allows the star tracker to work in an autonomous way, using only user commands sent through a laptop to Raspberry Pi using Wi-Fi. A protection case was design and built using the university’s manual milling machine. This case allows the electronic components to be safe when the star tracker is exposed to the humidity of the nocturnal environment. The star tracker was finally tested in the night sky, the furthest possible from light pollution, in order to test is performance and functioning.