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The GMRI robot is capable of inspecting hazardous zones of methane and/or coal dust explosion in hard coal mines. The robot enables remote measurements of the concentrations of methane, carbon monoxide, carbon dioxide, oxygen, temperature, and humidity. Cameras enable the robot to observe the state of the excavation. All electronic circuits of the robot, for measurements, control, transmission, and supply, are intrinsically safe. The transmission of data and control commands from/to the operators console are performed via an electric wire. Moreover, the wire enables to transmit intrinsically safe electric energy and is used to charge one of the accumulators. Thanks to that, the robot can operate in an isolated excavation for 3 months. An intrinsically safe pneumatic drive has been applied for setting wheels in motion. The non-commercial robot prototype was tested in a real excavation in an active hard coal mine. The technical solutions have been presented in the paper.

This paper presents the stands for strength tests of materials and structures with digital control systems, designed and built at the Department of Mechanics and Machine Design, Opole University of Technology. The authors described electrohydraulic strength stands for tests under uniaxial tension – compression, biaxial tension – compression of cruciform specimens, and electromechanical stands for tests under cyclic bending and torsion with phase shift, and under polyharmonic bending with torsion. Fatigue tests which could be performed on these stands as well as algorithms of controllers were presented.

The paper presents strength machine control system for characterization of fatigue properties of materials based on a new, recently defined, energy fatigue damage parameter. It is used in new procedure for precise determination of the fatigue characteristics of materials with the controlled strain energy density parameter. The new parameter distinguishes positive and negative values strain energy density histories during variable loading. In case of modern, cyclically unstable materials the new closed-loop control system of strength machine allows to univocally establish the relevant stress-strain based fatigue characteristic under bending and torsion. This control system has been implemented with the use of National Instruments LabVIEW software. The mechatronic stand based on fatigue machine for material testing under bending moment and torsion moment has been described and preliminarily material tests have been done.

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