Visual echolocation concept for the colorophone sensory substitution device using virtual reality

Detecting characteristics of 3D scenes is considered one of the biggest challenges for visually impaired people. This ability is nonetheless crucial for orientation and navigation in the natural environment. Although there are several Electronic Travel Aids aiming at enhancing orientation and mobility for the blind, only a few of them combine passing both 2D and 3D information, including colour. Moreover, existing devices either focus on a small part of an image or allow interpretation of a mere few points in the field of view. Here, we propose a concept of visual echolocation with integrated colour sonification as an extension of Colorophone - an assistive device for visually impaired people. The concept aims at mimicking the process of echolocation and thus provides 2D, 3D and additionally colour information of the whole scene. Even though the final implementation will be realised by a 3D camera, it is first simulated, as a proof of concept, by using VIRCO - a Virtual Reality training and evaluation system for Colorophone. The first experiments showed that it is possible to sonify colour and distance of the whole scene, which opens up a possibility to implement the developed algorithm on a hardware-based stereo camera platform. An introductory user evaluation of the system has been conducted in order to assess the effectiveness of the proposed solution for perceiving distance, position and colour of the objects placed in Virtual Reality

Technical condition diagnosing of the cableway supports' foundations

The paper presents a test subject, which is a set of cableway support towers, and issues related to its diagnostics. The paper’s essential part of the paper concerns proposed method for evaluating technical condition of joints between tower's supporting structure and its foundation, which is based on vibrations' acceleration of joints' elements tests results analysis. The final part presents analysis results for one of tested supports, obtained before and after an overhaul

Use of the K-Nearest Neighbour Classifier in Wear Condition Classification of a Positive Displacement Pump

This paper presents a learning system with a K-nearest neighbour classifier to classify the wear condition of a multi-piston positive displacement pump. The first part reviews current built diagnostic methods and describes typical failures of multi-piston positive displacement pumps and their causes. Next is a description of a diagnostic experiment conducted to acquire a matrix of vibration signals from selected locations in the pump body. The measured signals were subjected to time-frequency analysis. The signal features calculated in the time and frequency domain were grouped in a table according to the wear condition of the pump. The next step was to create classification models of a pump wear condition and assess their accuracy. The selected model, which best met the set criteria for accuracy assessment, was verified with new measurement data. The article ends with a summary

Destruction mechanisms of Cu-ETP copper guides for sectional insulators of railway traction

This article presents the results of a research on the operational damage to sectional insulator guides made of hard electrolytic copper Cu-ETP (Electrolytic Tough Pitch Copper). The guides were used on various rail routes, in real conditions, on which the trains ran at maximum speeds between 40 and 120 km/h for periods of 6 or 12 months. The microstructure of the surface, the working layer of the guide, which contacts the graphite plate of the current collector and the cross-section of the guide in the place where it was damaged was examined using the Olympus light microscope. The analysis of the chemical composition in the EDS micro-regions was performed using the Zeiss Supra 53 scanning electron microscope (SEM), while the qualitative X-ray phase analysis was performed with the use of the Panalytical X'Pert diffractometer. Scratches and deformations of the surface layer characteristic of the phenomenon of friction caused by the current collector were observed in the microstructure of the damaged parts of the guides of section insulators. The effect of a very intense oxidation process was also observed, as well as the effects of an electric arc, which according to the author, is the factor that has the most destructive effect on the condition of the guides

Aktywne zawieszenie pojazdu z ograniczonym zuzyciem energii : praca doktorska /

Praca doktorska. Akademia Górniczo-Hutnicza im. Stanisława Staszica (Kraków), 2006.Bibliogr. k. 147-152.Analiza sterowanych zawieszeń pojazdu, przegląd istniejących rozwiązań, struktur kinematycznych, aktywne elementy wykonawcze stosowane w zawieszeniach, wskaźniki jakości dla aktywnych zawieszeń pojazdów, algorytmy sterowania aktywnym zawieszeniem, analiza sygnałów sprzężenia zwrotnego, algorytmów sterowania, modelowanie matematyczne zawieszenia, model matematyczny zespołu aktywnego, ćwiartkowy, parametryczny, fenomenologiczny, linearyzacja modelu fenomenologicznego, identyfikacja obiektu, weryfikacja modelu na stanowisku laboratoryjnym, właściwości dynamiczne struktury równoległej, sterowanie, synteza regulatorów, dobór wzmocnień regulatora PID, badania symulacyjne, regulator modalny ze sprzężeniem od zmiennych stanu, analiza właściwości dynamicznych układu zamkniętego, regulator optymalny liniowo-kwadratowy LQ, synteza obserwatora stanu, analiza wpływu zmiany wartości wzmocnień macierzy K na właściwości dynamiczne aktywnego układu redukcji drgań, stanowisko laboratoryjne, badania elementów zawieszenia, opis stanowiska badawczego, konstrukcji mechanicznej, zespół elektrohydraulicznego wzbudnika drgań mechanicznych, stacja zasilania hydraulicznego, układ pomiarowo-sterujący, badania elementów sprężystych, tłumików wiskotycznych, aktywnego zespołu wykonawczego, dla różnych układów sterowania, układ z regulatorem PID, modalnym, porównanie wyników badań dla różnych regulatorów sterujących aktywnym elementem wykonawczym, układu z ograniczonym zużyciem energi

Materials used in the combat aviation construction

In this work, an attempt was made to apply laser surface technology for enhancement of the properties and strengthening the material with addition of ceramic phases in the form of silicon and tungsten carbide particles, leading to a remarkable increase in hardness. Thanks to rapid cooling caused by heat being transferred to the cold substrate, an advantageous, fine-grained structure develops, showing higher gradient morphology; furthermore, the surface layers obtained with laser alloying offer greater heat-resistance and anti-corrosion properties, as well as high wear resistance in addition to the aforementioned hardness, which increases by as much as 15% for the AlSi9Cu4 alloy compared with the alloy after standard heat treatment. Such an increase in the values of the mechanical properties makes it possible to use the investigated alloy in applications including, e.g., recyclable thermally exposed surfaces, such as pistons in internal combustion engines, which enables further decrease in the weight and the thermal expansion with simultaneous increase in the strength, reduction in fuel consumption, and increase in carrying load, speed, and range, which generates the need for further research into the area

NATURAL AGEING EFFECTS ON MICROSTRUCTURE AND PROPERTIES OF RAIL FASTENING ELEMENTS SKL-12

Rail transport is presently one of the most supported means of transport in Europe; it existed from the end of the 18th century. However, some issues especially concerning materials and its exploitation are still actual and are a matter of scientific projects or developments. In this paper, analyses concerning the characterisation of used track infrastructure elements in form of sleepers of the popular rail fastening system SKL 12 were performed. Specifically, the main objective of the work was the characteristics of the material microstructure and properties after long-term usage and natural ageing, reaching over a few decades. In this paper was conducted investigations concerning the non-used and used fasteners by reason of classic material research methods. The analysis was carried out based on the results obtained through research using mainly light, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), as well as electron diffraction for the lattice structure determination, EDS chemical microanalysis and Rockwell hardness testing were also carried out in terms of identification of the chemical analysis changes that occurred after long-term application. The main reason was to characterise the long-term usage for the microstructure changes on the surface layer of the used fasteners compared to newly produced material

Structure and Properties of the S49 Rail after a Long Term Outdoor Exposure

The subject of the research in this work was the S49 rail made of R260 rail steel (1.0623). The carried out investigations concern microstructure tests and tests of mechanical properties of rails after several years of exposure in the open air without usage. The purpose of the work was to determine on the basis of the results of research the possibilities of using the tested rail for usage and application for the construction of tracks on railway sidings. For investigations there were used diverse techniques reaching such engineering materials investigations like light or scanning electron microscope for microstructure investigations, as well as hardness and microhardness test were performed for determinations of the microstructural changes occurred in the upper area of the rails surface. The microstructure changes concerns especially the ferritic and pearlitic structure and the breaks in the present carbide mesh. During investigations it was found out that the tested railway rails are fully useful for application, after machining to achieve required dimensional parameters. It is also of high importance, of the economical point of view, that their price, also in case of earlier installation of the rails, may be lower than the current price offered on the marked for a entire new product. The price difference reaches dimensions in the range of 5% - 10%