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121	Návrh repliky letounu L-40 "Meta Sokol" - základní rozměry - technologie / Replica design of Aircraft "Meta Sokol" - Basic dimensions - technology Lipková, Alica January 2008 (has links) The object of the diploma thesis is a preparation of fundamentals for realization for replica of the aircraft L-40 „Meta Sokol“ matching the requirements of Certification Specification for Very Light Aeroplanes (CS-VLA). The preamble of the work deals with the changes made on the original aircraft necessary to satisfy the criterias of the above-mentioned specification. One of the main contents of the first part of the thesis is the definition of replica’s basic dimensions and preparation of aerostatic fundamentals, including longitudinal stability control. As next a suitable engine is chosen and calculation of corresponding performances is made. A detailed weight analysis and a determination of centre of gravity position (c.g. position), important for solving the stability of an airplane, is also presented. Finally, a brief description of the manufacturing process of individual components and also factors influencing the technology are discussed.
122	Rekonstrukce sportovního letounu M-2 Skaut - zástavba pohonné jednotky. / Reconstruction of Sport Aircraft M-2 Skaut - Mounting of Power Unit. Zakopal, Libor January 2008 (has links) This diploma thesis deals with the design of an engine mount for the M-2 Skaut aircraft on the basis of LSA and CS-VLA specifications. It is divided into several sections: analysis of input conditions, determination of factors which influence the geometry, the main design and its verification using the Finite Element Method. The FEM is compared with an analytical solution to determine its accuracy. This thesis also deals with a selection of acceptable propelers for this engine along with a basic design of an oil and fuel system.
123	Modifikace letounu RAPID 200 pro vlekání / Modification of RAPID 200 Aircraft for Towing Seďa, Ondřej January 2010 (has links) This master’s thesis deal with design modification of the RAPID 200 (Skyleader 200) airplane for towing at compliance with maximum take-off weight 450 kilogramme. A necessary construction modification, a weight analysis these adjustments and a balance verification are included. The thesis contains of power plants installation consisting from the M 132 engine and the V 541.2 propeller, a towing gear and a landing gear, a load calculation of power plants and towing gear and basic flight performance calculation too. Last but not least valuation of operation ekonomy, operation characteristics assesment and a using of the airplane for specialized duty are included.
124	Návrh řídicího algoritmu pro stabilizaci letadla / Control algorithm for aircraft stabilization Novák, Pavel January 2013 (has links) Master’s thesis: "Design of the control algorithm for aircraft stabilization" summarizes aircraft aerodynamics knowledge, from which nonlinear mathematical model of the aircraft and propeller propulsion system are created. Design of the control algorithm for angle position stabilization (for longitudinal motion) and the control algorithm for “Flight Path Angle hold“ and “Flight Level Change” modes is also presented here. Designed control algorithms are tested within the simulation of the real atmosphere at the end of the thesis.
125	Real-time Optimal Braking for Marine Vessels with Rotating Thrusters Jónsdóttir, Sigurlaug Rún January 2022 (has links) Collision avoidance is an essential component of autonomous shipping. As ships begin to advance towards autonomy, developing an advisory system is one of the first steps. An advisory system with a strong collision avoidance component can help the crew act more quickly and accurately in dangerous situations. One way to avoid colission is to make the vessel stop as fast as possible. In this work, two scenarios are studied, firstly, stopping along a predefined path, and secondly, stopping within a safe area defined by surrounding obstacles. The first scenario was further worked with to formulate a real-time solution. Movements of a vessel, described in three degrees of freedom with continuous dynamics, were simulated using mathematical models of the forces acting on the ship. Nonlinear optimal control problems were formulated for each scenario and solved numerically using discretization and a direct multiple shooting method. The results for the first problem showed that the vessel could stop without much deviation from the path. Paths with different curvatures were tested, and it was shown that a slightly longer distance was traveled when the curvature of the path was greater. The results for the second problem showed that the vessel stays within the safe area and chooses a relatively straight path as the optimal way of stoping. This results in a shorter distance traveled compared to the solution of the first problem. Two different real-time approaches were formulated, firstly a receding-horizon approach and secondly a lookup-based approach. Both approaches were solved with real-time feasibility, where the receding-horizon approach gave a better solution while lookup-based approach had a shorter computational time. Nonlinear optimization nonlinear optimal control numerical optimal control real-time solution optimal braking receding horizon modeling ship model propeller forces rudder forces direct multiple shooting method discretization Other Mathematics Annan matematik
126	Разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением : магистерская диссертация / Development of design principles for small-size remotely controlled snow-and-swamp mobiles Шонохова, Н. А., Shonokhova, N. A. January 2018 (has links) Выпускная квалификационная работы выполнена на тему «Разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением». Расчетно-пояснительная записка содержит 198 листов, 90 рисунков, 16 таблиц, 11 источников, 42 приложения. Объектом разработки является малогабаритный снегоболотоход с дистанционным управлением, предназначенный для инженерно-изыскательских работ. Цель работы – разработка принципов построения малогабаритного снегоболотохода с дистанционным управлением, в том числе разработка новых узлов, выбор из ранее представленных, модернизация и реконструкция элементов, разработанных для других машин. В результате проведенной работы спроектированы 3 шнековых движителя, 4 подвески, 2 системы управления, также рассмотрены блоки задания скорости, кольцевые распределители импульсов и преобразователи «Код-напряжение». В проекте также рассмотрены вопросы безопасности труда, радиационная безопасность и природопользование и охрана окружающей среды. В разделе технико-экономических показателей приведены единовременные, текущие и приведенные затраты. / The goal of the research was to justify the selection of various structural elements and control systems on the basis of both design parameters and the analysis of assigned tasks. Thus, a number of existing designs of machines, propellers and suspensions were considered in the course of the study, all of which could be used for different purposes: for example, it is more rational to utilize motor-in-wheel propellers to glide over the water, since those are most lightweight and waterproof of all, and to choose a spring suspension – since it contains the minimal number of elements which could fail in the water medium. As to the systems of control, the selection of their control blocks is made on the criteria of reliability, since it is necessary to ensure no-failure operation of the system as a whole. As a result of the work, 3 screw propellers, 4 suspensions, 2 control systems were designed, and a few speed assignment blocks, circular distributors of impulses and number-to-voltage converters were considered. The project also analyses the problems of work safety, radiation safety, conservation and environment control. The section on project feasibility cites nonrecurring, current and reduced costs. СНЕГОБОЛОТОХОД ШНЕКОВЫЙ ДВИЖИТЕЛЬ ПОДВЕСКА СИСТЕМА УПРАВЛЕНИЯ ШАГОВЫЙ ДВИГАТЕЛЬ БЛОК ЗАДАНИЯ СКОРОСТИ MASTER'S THESIS SNOW-AND-SWAMP MOBILE SCREW PROPELLER SUSPENSION CONTROL SYSTEM STEP MOTOR VARIABLE-SPEED MOTOR SPEED ASSIGNMENT MOTOR CIRCULAR DISTRIBUTOR OF IMPULSES
127	Posouzení vybraných metrologických charakteristik měřidel bodové rychlosti vodního proudu využívající elektromagnetického principu měření / Metrological characteristics of current velocity meters using the electromagnetic principle of measurement Vítů, Martin Unknown Date (has links) This master’s thesis deals with the assesment of directional sensivity and accuracy of current stream velocity using electromagnetic induction meters in circumstances simulating the real measurement profiles condictions. The theoretical part of the thesis describes the issue of streamflow measurement in open channels and determination of the relevant measurement uncertainties. It also includes description of the hydraulic circuit and the subject current velocity meters. The experimental part of the thesis focuses on the effect of turbulence on the value and accuracy of measured velocity and directional sensivity of electromagnetic induction meters of current velocity. The results are compared with parameters given by manufacturers, research by other authors and with the metrological characteristics of hydrometric propellers, which are commonly used for streamflow measurement in open channels.
128	Development and study of noise generation from propellers / Utveckling och studie av ljud genererat från propellrar Anton Dunström, Anton, Skjernov, Fredrik January 2022 (has links) Noise generation from underwater activities propagates into the marine environment.For marine vessels the propulsion system generates the most noise during itsoperations. Naval vessels that want to operate without being detected want to controlthe sound generating properties of the vessel. To control the sound generatingproperties this project has been looking into the existing propeller of the submergedcraft Carrier Seal that is produced by James Fisher Defense. Then a new and bespokenpropeller has been developed with theories applied to minimize its noise generatingproperties. The properties of the propeller that have been altered is the number ofblades, blade area ratio, pitch and skew angle. These properties have been alteredwith aid of the open-source software for Matlab named Openprop. From the finalpropeller design a prototype was later produced, tested and compared to the existingpropeller of the Seal Carrier. To test and compare these two propellers a test procedurewith inspiration from NATO and the Swedish Defense and Research Agency (FOI) wasdeveloped. The results from the comparison show that the sound pressure level fromthe propeller spectrum could be lowered with 3 dB re 1 μP a for the vessels design speedand several blade tones could be eliminated entirely. Simultaneously the efficiency ofthe vessel is increased throughout its speed range.In conclusions the recommendation to JFD is to change their existing propeller tothis bespoken propeller as it has proven itself to better in every way during thesetrials. / Ljud som genererats under vatten sprider sig långt från källan där de uppstått. Frånmarina fartyg är det framdrivningssystemet som står för majoriteten av det genereradeljudet. För militära fartyg som inte vill upptäckas är det av yttersta vikt att minimeraljuden som genereras ombord. För att kontrollera detta har det här projektet riktatin sig på fartyget Carrier Seal som tillverkas utav James Fisher Defense (JFD) ochdess propeller. Den existerande propellern har analyserats och därefter har en nyoch förbättrad propeller utvecklats. Utvecklingen har gjorts genom att tillämpatillgängliga teorier som gått ut på att minska propellerns ljudskapande egenskaper.Propelleregenskaperna som har undersökts är antalet blad som propellern har, dessbladtäckningsgrad, stigning och skevningsvinkel. Dessa egenskaper har varierats medhjälp av mjukvaran Openprop som körs i Matlab för att hitta en kombination somgenererar mindre ljud än sin föregångare. Därefter har en prototyp tillverkats ochtestats för att sedan jämföras med den existerande propellern. Testproceduren somgenomförts har tagits fram med inspiration från liknande procedurer som genomförtsav NATO och FOI. Resultatet från jämförelsen visar att ljudtrycksnivån från propellernhar kunnat minskats med 3 dB re 1 μP a för hela propellerspektrumet vid farkostensmarschfart och flertalet bladtoner kunde elimineras helt och hållet. Samtidigt someffektiviten kunnat förbättras över hela fartområdet.Slutsatsen som kan dras av arbetet är att JFD rekommenderas att byta deras nuvarandepropeller till den förbättrade propellern eftersom den har visat sig avsevärt mycketbättre under dessa tester. Silent propellers Propeller development Noise generation Skew angle Blade Area Ratio Openprop NATO STANAG no. 1136 James Fisher Defense. Tysta propellrar Propellerutveckling Ljudskapande Skevningsvinkel Bladtäckningsarea Openprop NATO STANAG no. 1136 FOI James Fisher Defense. Vehicle Engineering Farkostteknik
129	New modelling and simulation methods to support clean marine propulsion Grant, Michael 24 August 2021 (has links) The marine industry has increased its adoption of pure-electric, diesel-electric, and other non-traditional propulsion architectures to reduce ship emissions and fuel consumption. While these technologies can improve performance, the design of a propulsion system becomes challenging, given that no single technology is superior across all vessel types. Furthermore, even identical ships with different operating patterns may be better suited to different propulsion technologies. Addressing this problem, previous research has shown that if key elements of a vessel's operational pro file are known, simulation and optimization techniques can be employed to evaluate multiple propulsion architectures and result in a better propulsion system design and energy management strategy for a given vessel. While these studies have demonstrated the performance improvements that can be achieved from optimizing clean marine propulsion systems, they rely on vessel operational profiles obtained through physical measurement from existing ships. From a practical point of view, the optimization of a vessel's propulsion system needs to occur prior to a vessel's construction and thus precludes physical measurement. To this end, this thesis introduces a marine simulation platform for producing vessel operational profiles which enable propulsion system optimization during the ship design process. Core subsystem modules are constructed for simulating ship motions in 3 degrees of freedom and result in operational profile time-series, including propulsion power. Data is acquired from a benchmark vessel to validate the simulation. Results show the proposed approach strikes a balance between speed, accuracy, and complexity compared with other available tools. / Graduate model-based design MBD hybrid marine propulsion optimization simulation ship vessel DOF motion propeller torque thrust diesel-electric all-electric EV FES BES PHES HES ESS energy automation autonomous resistance hull ocean current added mass platform CFD hybrid electric batteries ultra capacitors emissions fuel consumption LNG motor engine energy management strategy control power energy wind waves strain coefficient hydrodynamic derivative MMG Maneuvering Modeling Group manoeuvring ferry design electric diesel azimuth thruster podded fouling roughness autopilot

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