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Overview of aircraft technology solutions compatible with the concept of mea
Get PDFThe purpose of this paper is to present some selected issues relating to the alternative application of the perspective concept on the plane board MEA (More Electric Aircraft), instead of the traditional solution, in terms of power (pneumatic and hydraulic systems). In the context of the analysis of this trend, particular attention is paid to the major advantages that aeroplanes have, made in accordance with the new technology and problems in autonomous systems of electricity generation (electric power grid of aircraft). Considering that the largest growth of the above trend of electric aircraft (MEA) applies to civil aviation, the most important role in this paper was assigned to civilian aircraft (Boeing, Airbus) in the context of power distribution in electro-energy systems. In addition, a review of air sources of electricity (electric power) generation was made for particular types of energy sources (generators, generator-starters, transformers, converters, etc.) and advanced on-board autonomous power systems ASE (Autonomous Electric Power Systems), used in most modern aircraft constructions (passenger and military aircraft). In the final part of this paper, based on a literature review of electric aircraft concepts (MEA) and a brief analysis, the main conclusions arising from the application of this trend in modern aviation are presented
Analysis, Mathematical Model and Simulation Tests of the Unmanned Aerial Vehicle Control System
Get PDFThe subject of this paper is to analyze, create a dynamic mathematical model and, on this basis, conduct simulation tests of the control system used in unmanned aerial vehicles. The key objective of the work is to develop a mathematical model of a control system based on the conducted studies of P, PI and PID regulators. The summary of this article are selected simulation tests of the proposed unmanned aerial vehicle (UAV) control system based on the analysis performed, the mathematical model developed for the dynamic control system and based on them, drawing practical conclusions
Examination of the Unmanned Aerial Vehicle
Get PDFThe contemporary interdisciplinary field of knowledge, which is the robotics used in unmanned aerial vehicles, is developing very dynamically. In view of the above, the authors of this paper have set themselves the following thesis: it is possible to build a flying mobile robot based on a controller with low computing power and a simple PID controller, and in this respect they undertook to prove it. The examined object in real experiments was the Quadrocopter. The article discusses the tasks implemented during the design and practical implementation of a remotely controlled flying unit. First, a mathematical model describing the dynamics of the UAV movement was defined. Then, electronic components were selected to allow the quadrocopter to fly. The board has a central unit in the form of the ATmega644PA microcontroller. In the following, the process of programming subsequent elements that make up the quadrocopter control program was carried out. The control system for stabilizing the machine requires information about the location of the quadrocopter in space. This is accomplished by a measurement module containing an accelerometer and a gyroscope. In addition, the quadrocopter needs information about the potential operator's commands. In the final part of the article, based on the analysis of the research subject, the mathematical model created and the necessary simulation tests carried out in this area, practical conclusions were presented
The Study of Permanent Magnets Synchronous Machine (PMSM) of the Autonomous Electric Power Supply System (ASE), compatible with the Concept of a More Electric Aircraft (MEA)
No full textBased on the analysis and mathematical models of synchronous electric machines (motor/generator), basing on permanent magnets, presented in this paper, the main importance of alternator AC power sources in the form of starter/generator (for conventional aircraft) and in the form of integrated unit starter (motor)/AC synchronous generator S/G AC (with respect to advanced aircraft concept in terms of more electric aircraft) was highlighted. Additionally, through the analysis and selected simulations of the on-board autonomous power supply system of the modern aircrafts, sources of electrical energy (synchronous motor/generator, integrated unit starter/AC generator) were located in board autonomic power system ASE (EPS, PES). Main components of this system are the electro-energetic power system EPS and the energo-electronic power system PES. In addition, the analysis and exemplary simulations of main electricity sources based on mathematical models have contributed to highlighting the main practical applications in accordance with the concept of MEA
Analysis, Mathematical Model and Selected Simulation Research of the GNSS Navigation Receiver Correlator
No full textThe article presents a mathematical model describing the physical phenomena occurring in the GNSS radio receiver. The main subunit which focused attention was the system of GNSS receiver correlator. The process of tracking and acquiring navigation signals processed in a navigational radio receiver was analyzed in a special way. Bearing in mind that all kinds of noise and interference get through to the signals processed in the receiver, the article attempts to develop a mathematical model of the signal reaching the receiver with noise and an inappropriate signal. On the basis of the mathematical model developed, the courses of acquisition and tracking processes of SIS signals in the presence of noise and interference signal in the form of a narrow and broadband signal are presented. The final part the paper presents the results of computer simulations. Although the results presented in the paper refer to a specific GNSS receiver, they may differ depending on the types of radio navigation devices
Model and Simulation of Permanent Magnets Synchronous Machine (PMSM) of the Electric Power Supply System (EPS), in Accordance with the Concept of a More Electric Aircraft (MEA)
No full textBased on the mathematical model of synchronous electric machine, basing on permanent magnets, presented in this paper, the key importance of alternator AC power sources in the form of generator (for conventional aircraft) and in the form of integrated unit starter/AC synchronous generator S/G AC (with respect to advanced aircraft concept in the field of more/all electric power MEA/AEA) was highlighted. In addition, through the analysis and selected simulations of the power supply system of a modern aircrafts, sources of onboard electrical energy (synchronous generator, integrated unit starter/AC generator) were located in board autonomic power system ASE (EPS, PES). Key components of this system are the electro-energetic power system EPS and the energo-electronic power system PES. Additionally, the analysis and exemplary simulations of key electricity sources based on mathematical models have contributed to highlighting the main practical applications in line with the trend of a more electric aircraft
Studies of 4-rotor unmanned aerial vehicle UAV in the field of control system
No full textThe key goal of this work was to develop a functional mathematical model of a 4-rotor UAV, including regulatory apparatus and identification of its parameters. The functionality of a quadrocopter traffic control has been reduced to solving differential equations that define the motion and dynamics of an unmanned aerial vehicle. It should be noted that the synthesis of the quadrocopter control system is not an easy task, due to the non-linear nature of the dynamics of this object and its structural instability. Therefore, in this article the tested object UAV was accepted as a physical model, which may cause potential material damage resulting from damage to the device as well as other elements that are located in its immediate surroundings. In addition, the article discusses the problem of improving the quality of the estimation rate of climb of unmanned aircraft of vertical takeoff and landing UAV, this problem was considered for the object in the low-ceiling range, i.e. in the range of 0-6 m, so the issue concerns autonomous take-off and landing. For the presentation of the results, the 4-rotor UAV was used, with the use of a proportional-integral-derivative PID controller in the context of the control system. The obtained results were supported by research and analysis of real results - the discussed algorithm was implemented in the 4-rotor UAV driver
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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