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The growing applications area of an electromagnetic launcher lead to numerous researches on new constructions and analyzes of existing and novel solutions of this type of device. The typical solutions with a coil or rail drive (named coil-gun and rail-gun) as well as a new hybrid construction which is a combination of these two types of drives are known. The paper presents the construction and mathematical model of the hybrid electromagnetic launcher (containing coil-gun and rail-gun module) with pneumatic assists, but the main purpose of this paper is to present measurement and simulation results of rails deformation for an electromagnetic launcher with rails (rail-gun module). The computer simulations were made using Inventor Professional software. In the measurement system the laser displacement sensor was used. [ABSTRACT FROM AUTHOR]

External fiber-reinforced polymer overlays have become the most popular method of building structures' strengthening on a global scale. Since no widely used and reliable methods for diagnosing the connection of overlays with the strengthened surface have been developed so far, developing such a method with the entire system, enabling easy and reliable use, has become a vital need of the construction sector. The paper presents an original infrared-based diagnostic module placed on a drone, enabling docking under the structure and conducting precise, uninterrupted diagnostics. The article describes the solutions and configuration of the automatic drone control system and the diagnostic module in all phases of its operation. The embedded measurement and control system has a multi-level structure distributed between the onboard automation system and the ground control station. Laboratory and field tests have shown that the road viaduct solution accurately reproduces joint damage, enabling the assessment of the structure's safety. • A thermography-based device for diagnosing the quality of the bond of FRP strengthening with a concrete surface was constructed. • The diagnostic module was placed on a flying platform in order to perform tests on hard-to-reach structures. • The proposed unmanned multi-rotor platform is equipped with a system that allows docking under the structure for testing and precise graphical data collection. • By creating a unique docking platform, automated processes for flight, approach to structure, docking, measurement and departure have been developed. • Laboratory and field tests show that the road viaduct solution accurately maps bond damage, enabling the estimation of load capacity of strengthened structural elements. [ABSTRACT FROM AUTHOR]

The paper presents the concept of the throttle-return valve dedicated for magne-torheological fluid. Basic properties of the magnetorheological fluid, valve conception and field calculations were presented. [ABSTRACT FROM AUTHOR]

Displacements or deformations of materials or structures are measured with linear variable differential transducers (LVDT), fibre optic sensors, laser sensors, and confocal sensor systems, while strains are measured with electro-resistant tensometers or wire strain gauges. Measurements significantly limited to a point or a small area are the obvious disadvantage of these measurements. Such disadvantages are eliminated by performing measurements with optical techniques, such as digital image correlation (DIC) or electronic speckle pattern interferometry (ESPI). Many devices applied to optical measurements only record test results and do not cooperate with the system that exerts and controls load. This paper describes the procedure for preparing a test stand involving the Digital Image Correlation system ARAMIS 6M for remote-controlled loading. The existing hydraulic power pack (ZWICK-ROELL) was adapted by installing the modern NI cRIO-9022 controller operating under its own software developed within the LABVIEW system. The application of the DIC techniques to directly control load on the real structure is the unquestionable innovation of the described solution. This led to the elimination of errors caused by the test stand susceptibility and more precise relations between load and displacements/strains which have not been possible using the previous solutions. This project is a synergistic and successful combination of civil engineering, computer science, automatic control engineering and electrical engineering that provides a new solution class. The prepared stand was tested using two two-span, statically non-determinable reinforced concrete beams loaded under different conditions (force or displacement). The method of load application was demonstrated to affect the redistribution of bending moments. The conducted tests confirmed the suitability of the applied technique for the remote controlling and recording of test results. Regardless of the load control method (with force or displacement), convergent results were obtained for the redistribution of bending moments. Force-controlled rotation of the beam section over the support was over 50% greater than rotation of the second beam controlled with an increase in the displacement. [ABSTRACT FROM AUTHOR]

This paper presents the results of research concerning multilayered epoxy composites reinforced with different materials. The strength of multilayered composites depends, to a large extent, on the reinforcing material. The authors decided to compare the low velocity impact response and perform tensile strength tests on several composites, to ascertain the mechanical properties of the prepared composites. Five different reinforcing materials were provided for the research (two fabrics made from aramid fibers, two fabrics made from carbon fibers and one fabric made from polyethylene fibers). The composites were manufactured by the vacuum supported hand laminating method. The low velocity impact response tests were conducted with the use of a pneumatic launcher. Three strikers with different geometry (conical striker, hemispherical striker and ogival striker) were used. A comparison of the resulting damage to the composites after the impact of the strikers was based on the images obtained using an optical microscope; tensile tests were also performed. The experimental investigation showed significant differences in the mechanical properties of the composites, depending on the applied reinforcing material. It was found that, as a result of the impacts, less damage occurred in the composites which were characterized by a lower Young's modulus and a higher tensile strength. [ABSTRACT FROM AUTHOR]