This paper includes description of the technique that was applied for free-flight (drop) tests of the rocket-plane scaled model. The main aim of the experiment was to validate the numerical approach to be used to simulate the gliding flight of the rocket-plane, especially the transition between high to low angles of attack and the rocket-plane response to control. The primary goal of this paper is to show what kind of challenges must be addressed when planning the flight test campaign. This paper includes description of how the rocket-plane model was scaled and built, the model preparation, experimental design and flight procedure. This paper shows an overview of how the experiment can be planned for different scenarios and the lessons learned during the deep stall free-flight tests.
Symulatory pełnią obecnie istotną rolę w szkoleniu i trenowaniu personelu wojskowego. Pozwalają między innymi na ćwiczenie trudnych bądź niemożliwych do wykonania w rzeczywistości scenariuszy bojowych. Technologie symulacji wirtualnej rzeczywistości, jak również sposoby ich współdziałania między sobą oraz obiektami rzeczywistymi są ciągle rozwijane. Artykuł porusza zagadnienie interaktywnych rozproszonych symulacji, przedstawiając ich rozwój technologiczny oraz cele, jakie przyświecały ich autorom. Po analizie metod interaktywnych symulacji wirtualnej rzeczywistości sformułowano założenia projektu oraz interakcje zachodzące pomiędzy obiektami interaktywnego symulatora sytuacji powietrznej. Na końcu podjęto próbę stworzenia interaktywnego symulatora sytuacji powietrznej zgodnie ze sformułowanymi założeniami. W rezultacie udało się zaprogramować symulator pozwalający na badanie interakcji pomiędzy systemami ostrzegania radiolokacyjnego oraz pierwotnymi radarami naziemnymi. Nie udało się zrealizować wszystkich założeń, między innymi pełnej funkcjonalności ze standardem DIS, jednak projekt ten może być dalej rozwijany, pozwalając na wprowadzenie całkowitej kompatybilności z tym standardem. Opracowanie symulatora jest procesem wymagającym wielu założeń, ale także kompromisów.
EN
In the present day, simulators play a significant role in training military personnel. They allow, among other things, for practicing combat scenarios that are difficult or outright impossible to execute in reality. Virtual reality technologies are being constantly developed, as are the ways of their interaction with each other and with real objects. This article brings up the topic of interactive distributed simulations, presenting their technological developments as well as the goals of their authors. After the analysis of selected methods of interactive distributed simulations, project assumptions are formulated and interactions occurring between objects in virtual airspace are stated. The last part of the article describes the attempt of creating an interactive air situation simulator in accordance with the formulated assumptions. As a result of the work conducted, it was possible to program a simulator that allows us to study the interactions between radar warning receivers and ground based primary surveillance radars. Not all assumptions have been achieved, most notably full functionality with the DIS standard, however, the project can be further developed, allowing for full compatibility with this standard. Developing a simulator is a process that requires many assumptions, but also trade-offs. With correct assumptions and a standardised way of information exchange between simulators, it is possible to make a web of interoperable simulators.
The paper presents the results of a series of numerical research on the possibility of applying Artificial Neural Networks (ANNs) for ultimate strength calculations of selected parts of rotating machines. The layout and the principle of the algorithm operation were described, beginning from the general assumptions and then moving to the detailed description of the subsequent modules. The effects of applying the algorithm were presented on the example of the analysis of the compressor disc. The significant benefits of using it were the reduction of optimization time by about 40% and the disc weight reduction by 0.5 kg. Accuracy of ANNs was different in each iteration of a presented algorithm. Finally, high accuracy of neural networks was achieved with the following mean values of relevant indices reached in the last iteration: RMSE=0.5983, MAPA=0.0733 and R^2=0.99895. The further perspectives of undertaken research were defined at the end.
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Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego w Warszawie jest wojskową, publiczną uczelnią akademicką kształcącą od ponad 60. lat inżynierów oraz prowadzącą działalność badawczo-naukową dla potrzeb Sił Zbrojnych RP i gospodarki narodowej. Działalność dla potrzeb lotnictwa prowadzi w Wydziale Mechatroniki i Lotnictwa Instytut Techniki Lotniczej, który jest kontynuatorem działalności zapoczątkowanej w 1951 roku przez Fakultet Lotniczy WAT. Fakultet ten został powołany dla potrzeb kształcenia inżynierów lotnictwa mogących eksploatować ówczesne samoloty o napędzie odrzutowym. Obecnie kształcenie lotnicze prowadzone jest w Wydziale na kierunku lotnictwo i kosmonautyka. W zakresie działalności naukowo-badawczej, instytut ma znaczące osiągnięcia krajowe i zagraniczne m.in. w zakresie eksperymentalnych oraz numerycznych badań aerodynamicznych statków powietrznych i struktur lotniczych, wyznaczania właściwości termofizycznych materiałów, jak również w zakresie systemów awionicznych i uzbrojenia lotniczego. W Instytucie działa także certyfikowany ośrodek szkolenia lotniczego personelu technicznego zgodnie z wymaganiami EASA Part-147 w oparciu o certyfikat nadany przez Urząd Lotnictwa Cywilnego.
EN
Military University of Technology in Warsaw (MUT) is a military, engineering university operating over 60 years (since 1951). MUT educates students as well as cadets and conducts scientific researches for the needs of the Polish Armed Forces and national economy as well as defence sector. The Institute of Aviation Technology of the Faculty of Mechatronics and Aerospace is a part of Military University of Technology and conducts activities for the military and aviation industry. The Institute is a successor of the former Faculty of Aviation, which was founded in 1951. The Faculty was established for the training of the military aviation engineers who could maintain the jet-engine aircraft, entered the service in 60. of the previous century. Recently, the Faculty provides the higher education in the field of Aerospace Engineering for both military (cadets) and civil students. The scientifi c and research activities of the Institute are focused on numerical aerodynamic as well as tunnel investigations, airframe structure strength simulation, determination of thermophysical properties of aviation materials, and on-board avionics systems as well aviation armament. Integrated part of the Institute is the Training Centre of aviation maintenance personnel, certifi ed with EASA Part-147 requirements. and it base on a certifi cate issued by the Civil Aviation Authority.
We propose linear parameter-varying (LPV) model-based approaches to the synthesis of robust fault detection and diagnosis (FDD) systems for loss of efficiency (LOE) faults of flight actuators. The proposed methods are applicable to several types of parametric (or multiplicative) LOE faults such as actuator disconnection, surface damage, actuator power loss or stall loads. For the detection of these parametric faults, advanced LPV-model detection techniques are proposed, which implicitly provide fault identification information. Fast detection of intermittent stall loads (seen as nuisances, rather than faults) is important in enhancing the performance of various fault detection schemes dealing with large input signals. For this case, a dedicated fast identification algorithm is devised. The developed FDD systems are tested on a nonlinear actuator model which is implemented in a full nonlinear aircraft simulation model. This enables the validation of the FDD system’s detection and identification characteristics under realistic conditions.
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We optimize the Hohmann type bi-impulsive transfer between inclined elliptic orbits having a common center of attraction, for the four feasible configurations. Our criterion for optimization is the characteristic velocity ΔvT = Δv1 + Δv2 which is a measure of fuel consumption. We assigned the optimum value of our variable x (ratio between velocity after initial impulse and velocity before initial impulse) by a numerical solution of an algebraic eight degree equation. We have a single plane change angle α. We present terse new formulae constituting a new alternative approach for tackling the problem. The derivations of formulae of our treatment are simple, straightforward and exceptionally clear. This is advantageous. By this semi-analytic analysis we avoid many complexities and ambiguity that appear in previous work.
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The main objective of the presented research is an analysis of tribological properties of multilayered MoS2 solid lubricant coatings produced by diffusion synthesis. These coatings are applied to provide high serviceability of friction assemblies in air, helium environment and vacuum in the temperature range 300-973 K. The following configurations were used for wear tests: disk-on-disk with one annular ledge, disk-on-disk with three annular ledges and pin-on-disk.
PL
Głównym celem badań była analiza właściwości tribologicznych wielo-warstwowych powłok smarujących MoS2 wytwarzanych w procesie syntezy dyfuzyjnej. Powłoki takie stosowane są dla zapewnienia wysokiej jakości pracy węzłów tarcia w środowisku powietrza, helu i w próżni, w temperaturze od 300 do 973 K. W badaniach zużycia użyto następujących konfiguracji elementów testowych: tarcza-tarcza z jednym pierścieniowym występem tarcza-tarcza z trzema pierścieniowymi występami oraz trzpień-tarcza.
The origins of the aerospace industry go back many centuries. Everyone is familiar with the story of Icarus who having designed a pair of wings, attempted to fly. He was successful but flew too close to the sun, whereupon the adhesive used as wing fastening melted due to thermal radiation and his flight ended in disaster. At the time this would have been regarded as science fiction, but clearly some consideration had been given to aerodynamics ( for wing design), adhesives and thermal radiation.
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A three-dimensional rest-to-rest attitude maneuver of a satellite with flexible solar panels equipped by on-off reaction jets is studied. Results indicate that, under an unshaped input, the maneuver induces an undesirable motion of the satellite as well as vibration of the solar panels. Fuel-efficient input shapers are then applied to reduce the residual oscillation of its attitude. By reducing vibrations at several large-amplitude natural frequencies, the expected pointing precision of the satellite can be satisfied.
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