Arvutitehnika õppekava lõputööd

Selle valdkonna püsiv URIhttps://hdl.handle.net/10062/25563

Arvutitehnika lõputööd alatest 2010. aastast

Sirvi

Sirvi Arvutitehnika õppekava lõputööd Märksõna "estcube" järgi

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  • Pisipilt
    Kirje
    Designing, Implementing and Testing the Solar Power Harvesting System for ESTCube-1
    (Tartu Ülikool, 2011) Rantsus, Ramon
    Estonian Student Satellite project started in the summer of 2008 at Tartu University with the objective for promoting space and giving students a hands-on experience on developing space technologies. The main outcome of the project was pronounced to be a fully operational picosatellite ESTCube-1 - the first Estonian satellite. The goal of ESTCube-1 satellite is to deploy a single 10 meter long Hoytether in low Earth orbit using a centrifugal force. The success criteria for this objective is the deployment of the tether and the snapshot of the visual confirmation of the deployment. The successful tether deployment is needed to demonstrate technologies for a full-scale Electric Solar Wind Sail (ESAIL) test mission in the future. The concept of ESAIL has potential to become one of the most efficient space propulsion technologies in the history. ESAIL is based on the interaction between the positively charged particles in the solar wind with the positively charged tether net deployed from a satellite. Each tether is a fourfold Hoytether structure to be as light as possible, but to maintain the durability needed in the harsh space environment. The concept was proposed by Pekka Janhunen from Finnish Meteorological Institute (FMI) in 2006. The concept of ESAIL has potential to become one of the most efficient space propulsion technologies ever invented. ESTCube-1 Electrical Power System (EPS) is responsible for gathering power from solar panels, storing into batteries and distributing it to the whole system.The main goals of the current work were to: analyze solar panels characteristics and solar power harvesting concept; analyze the concept of Maximum Power Point Tracking (MPPT); analyze requirements for solar panel controller; propose a solar panel controller design for ESTCube-1; develop a solar panel controller prototype; test the algorithm of MPPT; test the efficiency of solar power harvesting. The work consists of eight Chapters. The Chapter 3 gives a more detailed overview of ESTCube-1 satellite with focus on EPS subsystem. Chapter 4 analyzes the concept of solar power harvesting and the need of MPPT. Also the general characteristics of solar cells are analyzed and the simple model of solar cell work is pointed out. Chapter 5 proposes the design layout of solar panel controller, the implementation of MPPT algorithm and the implementation of solar panel controller software. Based on the design layout, the solar panel controller prototype development with measurement analyzes are described in Chapter 6. Chapter 5 and 6 form the main body of the work. In Chapter 7 the future activities are proposed and in Chapter 8 most important results are concluded and the completion of goals is assessed.
  • Pisipilt
    Kirje
    ESTCube-1 elektromagnettõukurite automatiseeritud kerimisseadme arendus ja testimine
    (2012-05-30) Uiboupin, Tõnis
    Eesti Tudengisatelliidi projekt alustas 2008. aasta suvel Tartu Ülikoolis eesmärgiga edendada kosmosetehnoloogiaalaseid teadmisi. Projektist on välja kasvanud Tartu Ülikooli, Tallinna Tehnikaülikooli, Helsingi Ülikooli, Saksa kosmoseagentuuri ja Eesti Lennuakadeemia tudengite täismõõduline rahvusvaheline koostöö. Projekti abil on õpilastel võimalik omandada olulisi praktilisi kogemusi teadustöö realiseerimisel ning projekti arendamisel algusest lõpuni. ESTCube-1 satelliit on esimene Eesti Tudengisatelliidi projekti raames arendatav satelliit. ESTCube-1 põhineb Cubesat standardil, mille töötas välja Kalifornia Riiklik Polütehniline Ülikool (California Polytechnic State University – Cal Poly) koostöös Stanfordi Ülikooliga. Standard on mõeldud peamiselt tudengisatelliitide projektideks ja see võimaldas muuta satelliitide ehitamise ja üleslaskmise palju odavamaks ning kättesaadavamaks. Selle bakalaureusetöö eesmärgiks on konstrueerida automatiseeritud elektromagnettõukurite kerija, selle arendamine, riistvaraliste ja tarkvariliste nõuete koostamine. Tõukurid on vajalikud ESTCube-1 satelliidi asendi määramise ja kontrolli süsteemis (ADCS – Attitude Determination and Control System). Antud lõputöö jaguneb viieks peatükiks. Esimene peatükk kirjeldab satelliidi asendi määramise ja kontrolli süsteemi eesmärki. Teises peatükis seletatakse lahti elektromagnettõukurite tööpõhimõte. Kolmandas peatükis käsitletakse loodud seadmele esitatud nõudeid ning tuuakse seadme tööpõhimõtte kirjeldus. Tehniline informatsioon loodud elektromagnettõukurite kerimisseadme kohta on leitav neljandast peatükist ning kõige lõpuks on viiendas peatükis antud seadme ning keritud tõukurite testimisenõuded.
  • Pisipilt
    Kirje
    ESTCube-1 satellite beacon
    (Tartu Ülikool, 2010) Kvell, Urmas
    ESTCube-1 shall be the first Estonian satellite to be launched in 2012. The mission has innovative scientific and educational objectives. The goal of ESTCube-1 satellite is to successfully deploy a single 10 meter long Hoytether structure in low Earth orbit using centrifugal force. The successful tether deployment is needed to demonstrate critical technologies for a full-scale Electric Solar Wind Sail (ESAIL) test mission in the future. The concept of ESAIL has potential to become one of the most efficient space propulsion technologies. It is based on the interaction between the positively charged particles in the solar wind with the positively charged tether net deployed from a satellite. Each tether is a four-fold Hoytether structure so it can be made very light but the whole structure shall retain the durability that is needed in a space environment. The concept was proposed by Pekka Janhunen from Finnish Meteorological Institute in 2006. ESTCube-1 is being developed by students from the University of Tartu and Tallinn University of Technology in tight cooperation with international partners from Finland (Finnish Meteorological Institute, University of Helsinki, Jyväskylä University) and Germany (DLR Bremen). ESTCube-1 communications subsystem (COM) is responsible for the communication between a ground station (GS) and the spacecraft. It can receive telecommands from the GS for setting different operating modes and requests to transmit data. There are two different types of downlink transmission modes: LPTM - Low Power Transmission Mode (Beacon) HPTM - High Power Transmission Mode (Data) The beacon is used for tracking the satellite and to get a simple overview of the satellite's status. The beacon data contains a small subset of telemetry data that is transmitted periodically in Morse code. The HPTM is used for transmitting large amounts of mission data. This consists of telemetry data from each subsystem and the experiment data, for example a picture taken by the camera. HPTM is turned on only after receiving a certain telecommand. The main goals of the current work were to: analyze other CubeSat projects beacon implementations; analyze requirements for ESTCube-1 beacon; determine optimal parameters for ESTCube-1 beacon (output power, transmission period, modulation, beacon data, operating frequency); propose a beacon design for ESTCube-1; analyze operational risks of the beacon design; develop beacon radio frequency (RF) electronics prototype; measure the output parameters of the prototype (signal purity, signal strength, on/off signal ratio. The work consists of ten Chapters. In Chapter 4, an overview of other CubeSat projects beacon implementations is given to see different solutions that are currently operational on orbit. Chapter 5 describes ESTCube-1 satellite in more detail with focus on COM subsystem. Chapter 6 analyzes requirements for developing a satellite beacon. Based on that analysis a beacon design is proposed in Chapter 7. Chapters 6 and 7 form the main body of the work. Chapter 8 describes the beacon radio frequency electronics prototype development and measurement analysis. In Chapter 9, the results of this work are discussed and future activities are proposed. In Chapter 10, most important of these results are concluded and the completion of goals is assessed.
  • Pisipilt
    Kirje
    ESTCube-1 Tether End Mass Imaging System Design and Assembly
    (2012-05-28) Kuuste, Henri
    The primary mission of the first Estonian student satellite, ESTCube-1, is to test the electric solar wind sail principle in ionospheric plasma. In order to accomplish this, the CubeSat standard based spacecraft will be launched into polar low-Earth orbit (LEO) and a small aluminium mass attached to the end of a 10 m long tether is to be reeled out using centrifugal force. The tether is then charged and the effect of ionospheric plasma on the angular velocity of the satellite is measured. During this experiment, the deployment of the tether needs to be verified. Therefore, an imaging system capable of capturing the tether end mass at various distances from the satellite has been developed. On ESTCube-1 this system is also used to carry out the secondary objective of Earth imaging for outreach purposes. Moreover, the camera has been designed as an independent module that is reusable in future spacecraft missions with extremely limited weight, volume, power, and communication bandwidth. The goals of this work were stated as follows: • List the requirements for the camera subsystem of ESTCube-1. • Design an independent, robust, and reusable camera module for use in small satellites. • Outline camera module firmware design. • Create software for camera control and testing. • Test the functionality and electrical characteristics of the resulting hardware. The research presented in this study was conducted over a period of one and a half years. During this time preliminary studies were conducted, two hardware prototypes and the final engineering model were constructed and tested. Several iterations of firmware and detailed test plans were developed.