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The development of aviation has set technological requirements that have conditioned the emergence and development of flight instrumentalization. The practical application of aviation for military and civilian purposes, the development of air traffic and technology in general, increase speeds, altitudes and flight lengths, while aircraft are becoming larger and more complex. From light wooden constructions and open cockpit, today planes fly long distances in all weather conditions, which brought the pilot and the construction of the aircraft to the endurance limit. At the beginning, during the pioneer period, flying was completely in the hands of the pilot and he made all the decisions based on his experience and psychophysical abilities. With the complexity of aircraft and flying, technological, ergonomic and safety conditions have an increasing influence on piloting technique. This paper describes the technological conditions and the development of instrumentation and flight automation systems. The application of the digital cockpit establishes many positive standards, but also raises questions about the further direction of aviation development. A special review describes the use and development of one of the basic instruments in the cockpit -the compass. This instrument is still, in an almost unchanged form, in the modern digital cockpit -glass cockpit.

Additive manufacturing involves manufacturing of products with complex geometry in relatively small quantities, as well as the tools and molds manufacturing for mass production. With additive manufacturing, digital models are being realized and implementation is huge in various industrial sectors. Compared to traditional manufacturing, the main parameters in the choice of additive technology are: energy savings, waste reduction, reduced use of more tools and optimization of design. Additive manufacturing or 3D printing technology works on the principle of adding material in layers, i.e. the model is formed from layers of molten material that is immediately cooled and solidified. 3D printing allows to work with customers to solve design problems before embarking on a launch production. The starting material for the model is polyactic acid (PLA). It is an eco-friendly thermoplastic polyester, that breaks down naturally. The mechanical characteristics of the realized PLA model are significantly influenced by various technological variables, such as following: nozzle diameter, thickness of defined layer, percentage of fill, sample size to be filled, filling rate and production temperature. The aim of this paper is to present the process of realization of an electronics enclosure for a compact pressure transmitter on a 3D printer. This gives the designer the possibility to correct existing errors, modify the product according to the wishes of the end users and finally provides a starting point for the prototype of new product.

In this paper is shown importance of modular architecture in the sustainable development of enterprises. The application of modular design enables the development of the production program based on the results of its own development. At the illustrated example, the production of transmitters it was concluded that modular architecture enables the production of independent entities, provides the realization of products in inaccessible places, enables to precisely defined technical documentation of modules, enabling easy maintenance, repair and improvement. This paper describes an algorithm for material reuse which indicates the importance of the customer in a closed material flow. In this connection, PLC includes protection of the environment as a strategic decision in the sustainable development of enterprises.

This paper presents a algorithm for the improvement of the manufacturing process developed and tested for small-scale enterprise. The validity of the algorithm can be seen through: defining basic elements, defining environmental factors, the importance of resources, and the analysis of input and output in the manufacturing process. The algorithm incorporates implemented strategies: remanufacturing and 4Rs. The paper analyzed the temperature transmitter at the end of its life circle. Reuse transmitter is realized through: checking, disassembly, replacement parts, cleaning, re-assembling and testing. The work provides an example of how to save energy and materials which appear as large losses in the manufacturing process.

This paper gives comparison and discussion of adhesives used for attachment of silicon piezoresistive pressure sensor dies. Special attention is paid on low pressure sensor dies because of their extreme sensitivity on stresses, which can arise from packaging procedure and applied materials. Commercially available adhesives “Scotch Weld 2214 Hi-Temp” from “3M Co.” and “DM2700P/H848” from “DIEMAT”, USA, were compared. First of them is aluminum filled epoxy adhesive and second is low melting temperature (LMT) glass paste. Comparing test results for low pressure sensor chips we found that LMT glass (glass frit) is better adhesive for this application. Applying LMT glass paste minimizes internal stresses caused by disagreement of coefficients of thermal expansions between sensor die and housing material. Also, it minimizes stresses introduced during applying external loads in the process of pressure measuring. Regarding the measurements, for the sensors installed with filled epoxy paste, resistor for compensation of temperature offset change had negative values in all cases, which means that linear temperature compensation, of sensors installed this way, would be impossible. In the sensors installed with LMT glass paste, all results, without exception, were in their common limits (values), which give the possibility of passive temperature compensation. Furthermore, LMT glass attachment can broaden temperature operating range of MEM silicon pressure sensors towards higher values, up to 120 ºC.

Material selection is the main challenge in the drone industry. In this study, hardness, abrasive wear, impact resistance, tensile strength, and durability (frost resistance and accelerated ageing) were identified as important characteristics of drone materials. The additive manufacturing technology was used to produce the drone leg specimens and prototype. The suitability of PETG as a primary filament material in the design of the drone leg was investigated. Nine series were printed with different raster lines (0.1, 0.2 and 0.3 mm) and infill densities (30, 60 and 90%). Printed specimens were annealed in salt and alabaster, as well as immersed in liquid nitrogen. Series with raster line-infill densities of 0.1–30, 0.3–30, 0.1–90 and 0.3–90 were identified as the most interesting ones. Thermally treated specimens had better mechanical and durability properties, and infill density was found to be the most important printing parameter. Specimen annealed in salt with a raster line of 0.1 mm and infill density of 90% had the best results. Since ABS is the most common material used for drone leg production, its properties were compared with the PETG specimen, which showed the best properties. The potential of PETG as an alternative material was proven, while the flexibility, productivity and suitability of the leg drone design were additionally confirmed. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to explore and define an adequate numerical setting for the computation of aerodynamic performances of wind turbines of various shapes and sizes, which offers the possibility of choosing a suitable approach of minimal complexity for the future research. Here, mechanical power, thrust, power coefficient, thrust coefficient, pressure coefficient, pressure distribution along the blade, relative velocity contoure, at different wind speeds and streamlines were considered by two different methods: the blade element momentum and CFD, within which three different turbulence models were analyzed. The estimation of the mentioned aerodynamic performances was carried out on two different wind turbine blades. The obtained solutions were compared with the experimental and nominal (up-scaled) values, available in the literature. Although the flow was considered as steady, a satisfactory correlation between numerical and experimental results was achieved. The comparison between results also showed, the significance of selection, regarding the complexity and geometry of the analyzed wind turbine blade, the most appropriate numerical approach for computation of aerodynamic performances. [ABSTRACT FROM AUTHOR]