Polish Institute of Aviation

Warsaw, Poland

Polish Institute of Aviation

Warsaw, Poland
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Wronicz W.,Polish Institute of Aviation
Fatigue of Aircraft Structures | Year: 2016

One crucial characteristic of the aircraft structure are fatigue properties and rivets are usually critical areas in metal airframes due to fatigue cracks nucleation. According to literature, the NACA riveting method offers a huge increase in fatigue life of riveted lap joints. This paper presents FE simulations of quasi-static riveting on a press for standard countersunk rivets and the NACA riveting in two configurations: with a normal brazier rivet and a brazier rivet with a compensator. The analyzed configurations have been compared based on the stress courses on the sheets faying surfaces after riveting process. Due to a lack of data, the rivet length and the squeezing force value were assumed for NACA riveting based on FE simulations. The results indicated beneficial influence of the NACA riveting in the outer sheet (with a countersunk) and disadvantageous influence in the inner sheet. This effect was stronger in the case of the rivet with a compensator. © 2016 Wojciech Wronicz, published by De Gruyter Open 2016.


Krysztofik J.,Polish Institute of Aviation
Fatigue of Aircraft Structures | Year: 2016

This paper presents the results of the quantitative evaluation of the degree of damage caused by plastic strain accumulated in static tensile tests and creep tests. To detect changes in the structure of the material and in order to determine the degradation of the materials, nondestructive methods were used, namely the ultrasonic and eddy current methods. In ultrasonic testing, attenuation and acoustic birefringence were used as damage indicators. In the case of the eddy current method, changes in the phase angle of impedance were observed in the material. The material tested was Inconel 718 alloy. Inconel alloys are often find application in extreme working conditions including in the power engineering industry, aviation and aerospace. A new type of specimen with the variable cross-sectional area of the measuring part was used in the tests. This allowed researchers to obtain a continuous distribution of plastic strain and enabled analysis of the material with respect to different damage degrees. The correlation between the degree of damage, expressed by the measure of deformation, and the value of nondestructive indicators was determined. On the basis of it, the dependence indicating the ability to nondestructive evaluation of the degradation degree of the material, subjected to loads exceeding the yield limit was obtained. © 2016 Józef Krysztofik, published by De Gruyter Open 2016.


Understanding of mechanisms and factors responsible for the driver behavior on the road is the subject of ongoing interest to transportation psychologists, occupational doctors and engineers. Models of driver behavior are a key point for the understanding the mechanisms and factors which may cause limitations to the optimal functioning on the road. They also systematize knowledge about the factors responsible for the behavior of the driver and thus constitute a starting point for formulating empirical or diagnostic hypotheses. The aim of this study is to present models of driver behavior from the descriptive and functional perspectives. © 2017, Nofer Institute of Occupational Medicine. All rights reserved.


Kalinowski M.,Polish Institute of Aviation
58th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, 2017 | Year: 2017

In this paper an automatic algorithm for preliminary design of inverted joined-wing with electric motor is presented. The algorithm is a modification of a traditional iterative design process changed for the purposes of a joined-wing aircraft. It synthesizes a few phenomena that have a major influence on the aircraft flight, e.g.: structural and aerodynamic behavior, balancing and performance. The design process involves the global search optimization process with total aircraft range set as an objective, thus it is suitable for seeking optimum solutions. Based on the presented algorithm, a computer program was created and used to improve the range of existing UAV joined-wing by 27.3%. © 2017, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.


Socha G.,Polish Institute of Aviation
ASTM Special Technical Publication | Year: 2017

Fatigue failure of elastic-plastic materials is the result of damage accumulation. In the initial phase, this process is controlled by plastic deformation. The standard method for the investigation of fatigue phenomena relies on counting the applied load (or strain) cycles to final failure or macro crack initiation. This method does not allow observations of fatigue damage accumulation during testing. Such observations can only be realized when a measurable physical quantity (representing damage) is selected for monitoring. Such a quantity, referred to as the damage indicator, must be proven to change in a monotonie manner with the progress of the damage. In this paper, two damage indicators will be proposed and discussed: local inelastic response and accumulated equivalent plastic strain. Local inelastic response can be referred to as the relative damage indicator when it changes in a monotonie manner during the entire life of the material. In the case of such an indicator, its actual value is compared with its initial value to estimate the amount of accumulated damage. This kind of damage indicator is useless in the case of materials exhibiting more complex behavior (e.g., initial cyclic hardening followed by softening). For such materials, accumulated equivalent plastic strain can be used as the damage indicator. This kind of indicator can be referred to as a cumulative damage indicator because it is necessary to use the cumulated value of such a quantity to estimate the amount of accumulated damage. Copyright © 2017 by ASTM International.


Rozanowski K.,Polish Institute of Aviation | Murawski K.,Military University of Technology
Acta Physica Polonica A | Year: 2013

The aim of the paper is to describe design of an optical sensor intended to analyze pupillary light reflex. It also presents the results of physiological adaptation mechanisms in human eye, i.e. response of the iris to changes in the intensity of light that falls on the retina of the eye under conditions of sensory deprivation. Pupillary light reflex is a closed loop nerve reflex. It controls the amount of light that reaches the retina. Based on the test results, an optical sensor was designed, fabricated and correctly calibrated. In comparative tests with the use of F2D Fit- -For-Duty, a commercial system by AMTech, selected pupillographic parameters were primarily evaluated (baseline pupil diameter, oscillations, reflex latency, maximum reaction time, pupil constriction time, pupil dilation time, and constriction amplitude) under conditions of diminished alertness, reduced ability to concentrate, increasing fatigue, and drowsiness. The solution comes as part of a mobile pupillography device intended to be assembled in cars and airplanes to identify conditions of lower alertness, reduced ability to concentrate, increasing fatigue and drowsiness in drivers, pilots and traffic controllers, and to trigger alarm and preventive measures, if necessary.


Rozanowski K.,Polish Institute of Aviation | Murawski K.,Military University of Technology
Acta Physica Polonica A | Year: 2012

The paper presents the optical sensor which is built for EyeTracker operating in car harsh environment. The sensor is based on USB high speed video infrared camera. Additional hardware was designed for control and emission of infrared light as well. The designed hardware and software of the sensor are described in the paper. Some results of work, including video processing, are also presented.


Murawski K.,Military University of Technology | Rozanowski K.,Polish Institute of Aviation
Acta Physica Polonica A | Year: 2013

The aim of the paper is to discuss research conducted at the Military University of Technology as well as the Military Institute of Aviation Medicine. The essence of the research is to develop a pattern recognition algorithm for the analysis of data received from an eye tracker sensor. Data analysis can be done using computer vision algorithms. In the article the state of the art pattern recognition algorithms were presented. Particular attention was paid to the possibilities and limitations of their use. The main part of the paper is the presentation of the author's pattern recognition algorithm. In the paper we have also shown the results obtained by other techniques of image processing, which are frequently used to determine the position of the pupil of the eye on the image.


The issues involved with recording vital functions in the magnetic resonance imaging (MRI) environment using fiber-optic sensors are considered in this paper. Basic physiological parameters, such as respiration and heart rate, are fundamental for predicting the risk of anxiety, panic, and claustrophobic episodes in patients undergoing MRI examinations. Electronic transducers are generally hazardous to the patient and are prone to erroneous operation in heavily electromagnetically penetrated MRI environments; however, nonmetallic fiberoptic sensors are inherently immune to electromagnetic effects and will be crucial for acquiring the abovementioned physiological parameters. Forty-seven MRI-tested or potentially MRI-compatible sensors have appeared in the literature over the last 20 years. The author classifies these sensors into several categories and subcategories, depending on the sensing element placement, method of application, and measurand type. The author includes five in-house-designed fiber Bragg grating based sensors and shares experience in acquiring physiological measurements during MRI scans. This paper aims to systematize the knowledge of fiber-optic techniques for recording life functions and to indicate the current directions of development in this area. © The Authors.


Kozak J.,Polish Institute of Aviation
Lecture Notes in Electrical Engineering | Year: 2013

Electrochemical machining (ECM) is an important manufacture technology in machining difficult-to-cut materials and to shape complicated contours and profiles with high material removal rate without tool wear and without inducing residual stress. This paper presents the physical and mathematical models on the basis of which of the simulation process module in the computer-aided engineering system (CAE-ECM) for ECM has been developed. The results of computer simulation of electrochemical sinking and examples of CAE-ECM system application are discussed. © 2013 Springer Science+Business Media.

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