AiMT Volume 10 (2015), Issue 1

Hyperspectral Data Conversion in the Case of Military Surveillance

Racek F., Baláž T. and Melša P.

The article deals with analysis of raw hyperspectral data conversion. There are mentioned some possible ways of data conversion and their comparison. The comparison is based on both the quality of conversion and the usability in military usage. The analysis is made on the real data taken from the experimental measurement. The quality of conversion is evaluated by matching the converted data with laboratory taken data.

Keywords: hyperspectral imaging, hyperspectral datacube, spectral reflection, spectral angle mapper

Pages: 5 - 13

Kinematic and Dynamical Modelling for Control of a Parallel Robot-based Surveillance/Sentry Device

Zavala-Yoé R., Ramírez-Mendoza R. A. and Chaparro-Altamirano D.

We contribute with a surveillance and defence system based on a 3SPS-1S parallel manipulator. The central constraining leg of the mechanism increases the stiffness of the system and forces the manipulator to have three pure rotation degrees of freedom. Determining inverse kinematics is trivial but solving forward kinematics is done by a numerical-geometrical approach obtaining a unique solution via artificial neural networks (ANN) and Newton-Raphson’s method. An optimized workspace is calculated with a genetic algorithm (GA) and singularities are also computed. Inverse and forward dynamics of the manipulator are also solved for control purposes. Three different designs are presented: one is a classical PID controller and the other two are fuzzy PD controllers. One of them works in sliding mode.

Keywords: Artificial intelligence, dynamics, fuzzy sliding mode controller, kinematics, parallel robots, surveillance systems

Pages: 15 - 30

Mechanical and Computational Design for Control of a 6-PUS Parallel Robot-based Laser Cutting Machine

Zavala-Yoé R., Ramírez-Mendoza R. and Ruiz-Garcia J.

A 6-PUS parallel robot is modelled, designed and controlled in terms of Newton – Euler equations in order to be implemented numerically. Direct and inverse kinematics as well as direct and inverse dynamics are analysed and solved. Direct kinematics is solved by introducing a novel numeric-geometric method here referred to as method of arcs. Next, direct and inverse dynamics problems are solved offering advantages traditional methods do not. Two types of controllers were implemented in order to get a desired performance. Two 3D robot designs are also shown. Numerical computations and simulations were developed in MATLAB. The whole design and control converges to a laser cutting machine application which is given at the end of the document.

Keywords: Parallel robot, Modelling, Control, Laser applications

Pages: 31 - 46

Theoretical and Technical Aspects of Optical Access Network Construction

Baštigál M., Čepčiansky G. and Schwartz L.

There are numerous telecommunication operators in the world who have started to replace old metallic cable networks by networks based on cables with optical fibres or to build completely new optical networks which cost a lot of money. To provide guidance to these costs, general theoretical formulae have been derived on simplified assumptions which should enable the basic orientation to the costs that the construction of an optical access network requires. The theoretically obtained results are compared with the practical solution of a real optical access network.

Keywords: optical access network, optical fibre, splitter, optical distribution point, optical access node, radial, or rectangular network configuration, attraction area, subscriber

Pages: 47 - 62

Evaluation of Static and Dynamic Properties of Energy Absorbers for Explosion Resistant Elements

Drdlová M., Frank M., Řídký R., Popovič M. and Buchar J.

This paper describes experimental investigation on the response of new advanced materials to low and high velocity load. The main aim of the experiments is to improve the behaviour of sandwich structures under dynamic loading, in particular explosion. Two types of porous raw particle materials based on expanded glass and ceramics in combination with polymeric binder were used to design a new type of blast wave energy absorber. The effect of binder amount and type of filler on the static and dynamic properties of designed materials was evaluated. Bulk density, compressive and flexural strength under quasi-static load were determined on prism specimens. Izod impact strength characteristics were evaluated as well. Numerical simulations were conducted to determine the dynamic response of the material in sandwich structure, using implicit/explicit solver LS-Dyna. As the last step, the developed material was used as the interlayer of blast resistant litter bin, and its functionality was verified by real field blast tests.

Keywords: blast energy absorber, expanded glass, expanded ceramics, numerical simulation, blast test

Pages: 63 - 72

Setting of the Optimal Parameters of Melted Glass

Luptáková N,. Matejíčka L. and Krečmer N.

This research is focused on the problems of setting the optimal parameters of melted glass in real conditions. To achieve the best quality of glass products, the striae (inhomogeneity) value must be the smallest or ideally minimal. In this paper, the value of striae is minimized from aspect of parameters of melting process p1, ..., pn by constructing a regression model in the form y = f(p1, ..., pn), where f is a polynomial of n variables. The description of the striae using a regression functions in glass industries is an original idea of the authors. This unique method has been developed in cooperation with developers in the development of a new innovative technology of production of glass. It is apparent that the optimal setting of parameters of melting process p1, ..., pn has both economic and practical importance (the parameters p1, ..., pn describe performance of electro – heating, the value of the actual off take of glass melt, the temperature of the front and rear zone of the gutter, the temperature at the bottom of the furnace etc.). Chemical striae have often negative effect on the glass properties, and the elimination of striae has been a key problem in glass science and technology. On the basis of the experiments and obtained results, it is possible to propose a method for minimizing the value of striae. Moreover, other important knowledge could be used for modernization and improvement of the process of industrial production of glass in practical application in military technologies.

Keywords: Striae, glass, glass melting, regression, optimal parameters

Pages: 73 - 79

Vital Area Identification – State-of-the Art

Malachová T. and Vintr Z.

When it comes to designing effective physical protection of a critical infrastructure against malicious attacks, the knowledge of potential targets of the attack or areas in which these targets are placed is the basic presumption. Without knowing the attack targets it is impossible to plan sensibly the physical protection system or evaluate its effectiveness. That is the reason why a great deal of attention is paid to the identification of targets or vital areas, and a number of methods and procedures which might be used for the targets identification have been developed. The article brings the results of the extensive analysis of the current state in this area. It includes a brief historical development of the processes of attack targets identification and introduces methods and approaches used within these procedures. Admittedly the attention is paid mainly to the identification of vital areas at nuclear facilities, but the performed analysis did not address only this area of highest attention, but also the systematically examined current state of a critical infrastructure in general.

Keywords: Target identification, vital area identification, physical protection system, fault tree, event tree, attack tree, protection tree

Pages: 81 - 96

SOKOL Unmanned Aerial System

Kuzdas J. and Pátek Z.

The SOKOL unmanned aerial system is intended for the military, police and the integrated rescue system operations. The system consists of the light small SOKOL unmanned airplane, the catapult launcher with the rubber bungee cords and the control system whose main part is the ruggedized PC tablet. The system features versatility, compactness and robustness that allow performing different missions at adverse weather and terrain conditions. The SOKOL meets the actual status of the Czech legislation of the UAV operations.

Keywords: Unmanned aerial system, unmanned aerial vehicle

Pages: 99 - 109

The Qualitative Analysis of the Selected Explosives Using Thin-Layer Chromatography

Lutonská T., Kobliha Z. and Skaličan Z.

A simple, economical and relatively quick method of thin-layer chromatography (TLC) has been applied to analyse four frequently used explosives, TNT, RDX, HMX and Tetryl that are a common part of significant military, industrial and improvised explosives. Silicon dioxide is proven to separate individual explosives at a stationary phase. Out of 38 tested, three types of two-component mobile phases consisting of petroleum ether and acetone in the ratio of 2:1 or 7:3 of a volume and hexane and acetone in the ratio of 2:1 of a volume are recommended. To detect explosives, the UV radiation with the wavelength of 254 nm is proposed.

Keywords: TLC, Explosives, TNT, RDX, HMX, Tetryl

Pages: 111 - 117

Fire-fighting Systems in Aircraft in the Service of Czechoslovakia and the Czech Republic since 1948

Zavila O., Chmelík R. and Trčka M.

Fire-fighting equipment is currently a common part of the technical equipment in transport, military and most recreational aircraft. But it was not always so. Aircraft fire protection systems and their historical development represent a very important but neglected chapter in the history of aviation and fire protection. This article provides a brief overview of extant information and technical points of interest that form the basis of today's fire protection systems in combat military aircraft. The article is specifically focused on trends in fire-fighting equipment in jet combat aircraft in the service of the Army of the Czech Republic and former Czechoslovakia since 1948.

Keywords: Army of the Czech Republic, Czechoslovak Army, Czechoslovak People's Army, halon, carbon dioxide, jet combat aircraft, fire extinguishing equipment, development trend

Pages: 119 - 133