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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&rsquo, s modulus and a higher tensile strength.

The purpose of this paper is to present a novel mechatronic system for gait re-education which consists of a body weight support system (BWS system) and a treadmill. This publication covers mainly issues related to the design and optimization process of a control algorithm dedicated for the unloading system. The proposed control system is based on a fuzzy logic controller coupled with a PID regulator. The optimization of parameters for regulators has been conducted based on numerical simulations in which a hybrid optimization method combining a genetic algorithm with a gradient algorithm has been used. The developed control system has been tested experimentally.

The paper deals with a modelling of electromechanical drive systems incorporating vector control unit. The algorithms of sensitivity analysis and optimization of dynamic features have been elaborated and applied for selection of design features of the system with the aim to minimize dynamic forces in kinematic pairs. The assumed dynamic model takes into account electromechanical couplings and enables computer simulation of dynamic phenomena occurring in kinematic pairs of the drive system for various initial conditions. It is shown that the optimization process is more effective when both mechanical and electromagnetic parameters are used simultaneously. The application of optimization procedures in the design process is an effective aid and may be applied for determining design features of the drive systems considered here.

The paper addresses analytical, numerical and experimental aspects of the design of controlled fluid damper. The mathematical model served the development of a numerical model in MATLAB/Simulink environment. The selected important aspects of the tracked vehicles dynamic modelling process related to dynamics of the drive system and the suspension of selected tracked vehicles are presented. The main aim of the article was to present the investigation results of the experimental studies of a prototype rotary shock absorber at various magnitudes of control current was presented in this paper. Simulation and preliminary experimental results comprising resistance force values as a function of angular displacement and angular velocity are presented.