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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.

Back-pressure air gauging is an effective and practical way of controlling machine parts in large-scale production. It is a non-contact measuring technique based on the flapper-nozzle effect. The proper functioning of a differential pneumatic comparator depends on several geometric parameters as well as flow conditions inside the device. The main problems of this controlling technique are the fouling of the measuring nozzle head and changes in the accuracy of the comparator. This paper examines the influence of the supply pressure, the diameter of the orifice in the measuring branch, and the axial distance in the flapper-nozzle area on pneumatic comparator performance. In a way, we are trying to optimize the performance of a given pneumatic comparator with respect to the tolerance field for which it is intended. The size, strength, and position of the vacuum in the flapper-nozzle area depend on the supply pressure and the axial distance between the measuring nozzle outlet cross-section and the workpiece surface. For a certain combination of these two parameters, we can influence the vacuum quantities. A pneumatic sensitivity of a comparator can be increased by increasing the supply pressure. The greater accuracy of the back pressure air gauge, the smaller the application range, i.e. the tolerance field that we can control with a given device.

The goal of this research is to assess the different low-cost sensors for flight altitude measuring of a multirotor UAV at low altitude flight. For optimizing the sensor performances and accuracy, data filtering and other methods were applied. The flight altitude data were collected and stored for later analysis with reference to the true altitude. The correlation coefficient and the mean squared error were calculated in order to assess the sensors' performance. On the basis of the results of the study, it was possible to determine the choice of the adequate sensor for this specific use. The study showed that the best characteristics for this experiment conditions had the Garmin LIDAR-Lite V3HP sensor and the Bosch Sensortech BME280 that combined air humidity, atmospheric pressure, and air temperature sensor.

Alternative propulsion fuels for diesel engines were highlights for a variety of research activities within a large number of R&D labs in the world. Curiosity, as well as basic interest in alternative fuel has been immense because of its reproducibility, renewability, as well as good ecological characteristics. Another reason for this interest is a favorable impact on the economies of the countries engaged in their production, by processing that kind of bio fuel. This paper presents the results of testing and research of the three types of alternative fuel gained from bio oil. Analyses and comparison of the dynamics of combustion process of these alternative fuels were done in relation to the reference diesel fuel. Burning process of methyl esters rapeseed (RME100), soya oil (SME100), waste cooking palm oil (PME100), as well as of regular Euro diesel fuel were investigated. It was found that these fuels were highly usable in diesel engines if they had been produced according to a proper standard procedure under standard EN 14214. The application of bio fuel is also very interesting for the propulsion of agricultural engines and machinery, because it enables the individual farming of bio fuel products necessary for the appropriate own machinery.

This paper demonstrates the approach to determination of cornering stiffness as the most important parameter of motor vehicle steering and stability systems through integration of empirical models and real exploitation parameters. The approach is based on the analysis of a tire mathematical model, identification of key real exploitation parameters and integration of a mechatronic system for tire load monitoring. Measurement of tire load and subsequent integration of measured values into developed software module provide a precise definition of cornering stiffness for a certain vehicle and road contact patch. This research assumes integration of a mathematical model and mechanical, electronic and information technologies with the aim of comprehensive understanding of tire behavior in terms of cornering stiffness determination.

This paper analyzes load distribution throughout the tank body suspension zone. It points out the importance of influence that the design of the link between the tank wall and the base of the tank vehicle (suspension cushion zone) has on the structure behaviour and reliability. In this study, the current state is considered, giving comments on the requirements and the criteria which make a normative regulation of this segment. The basic purpose of this study is to point out the inconsistency and inaccuracy of current regulations as well as to offer a technically adequate way of resolving the stated problems in the segment of identification of behaviour and verification of construction from the strength point of view. In addition, we have illustrated how a developed methodological approach has been applied to a particular model of self-supporting ADR tank body of semi-trailers in the fifth wheel coupling pin zone, including the characteristic graphic presentation of carried out calculations and necessary explanation and comments.

Iosif Taposu has formulated a mathematical model and generated a family of airfoils whose geometry resembles the dolphin shape. These airfoils are characterized by a sharp leading edge and experiments have proven that they can achieve better aerodynamic characteristics at very high angles of attack than certain classical airfoils, with the nose geometry inclined downwards. On the other hand, they have not been applied to any commercial general aviation aircraft. The authors of this paper have been motivated to compare the aerodynamic characteristics of widely used NACA 2415 airfoil with Taposu's Dolphin that would have the same principal geometric characteristics. A CFD calculation model has been established and applied on NACA 2415. The results were compared with NACA experiments and very good agreements have been achieved in the major domains of lift and polar curves. The same CFD model has been applied on the counterpart Dolphin 2415. Results have shown that the Dolphin has a slightly higher lift/drag ratio in the lift coefficient domain 0.1-0.35 than NACA. On the other hand, at higher and lower lift coefficients, its aerodynamic characteristics were drastically below those of the NACA section, due to the unfavorable influence of the Dolphin's sharp nose. A series of the Dolphin's leading edge modifications has been investigated, gradually improving its aerodynamics. Finally, version M4, consisting of about 70% of Dolphin's original rear domain and 30% of the new nose shape, managed to exceed the NACA's characteristics, thus paving the way to investigate the Dolphin hybrids that could be suitable for the general aviation industry. [ABSTRACT FROM AUTHOR]

Many studies have proved that elements of driver's behavior related to gear selection have considerable influence on the fuel consumption. Optimal gear shifting is a complex task, especially for inexperienced drivers. This paper presents an implemented idea for gear shifting optimization with the aim of fuel consumption minimization with more efficient engine working regimes. Optimized gear shifting enables the best possible relation between vehicle motion regimes and engine working regimes. New theoretical-experimental approach has been developed using on-board diagnostic technology which so far has not been used for this purpose. The matrix of driving modes according to which tests were performed is obtained and special data acquisition system and analysis process have been developed. Functional relations between experimental test modes and adequate engine working parameters have been obtained and all necessary operations have been conducted to enable their use as inputs for the designed algorithm. The created model has been tested in real exploitation conditions on passenger car with Otto fuel injection engine and on-board diagnostic connection without any changes on it. The conducted tests have shown that the presented model has significantly positive effects on fuel consumption which is an important ecological aspect. Further development and testing of the model allows implementation in wide range of motor vehicles with various types of internal combustion engines. [ABSTRACT FROM AUTHOR]