Solid State Phenomena Vol. 210

Abstract: Modelling of the dynamic behaviour of multi-staged gears by use of the discrete models can be carry out effectively for shafts having sufficiently high bending stiffness. In this report there have been examined the models of the two-stage gear considering influence of the intermediate shaft (countershaft) on the dynamic loads in both stages particularly. The model has a description of the meshing gears with clearance and technological imperfection of the wheels.

Abstract: Articulated tractors are wide available on the construction equipment market and have a lot of unique advantages not accessible in case of Ackerman steering system or truck-mounted tools. The only unsolved problem is their poor directional stability which significantly limits the speed of operation and work efficiency. This paper investigates the phenomenon of directional stability loss and indicates main reasons for its appearance by means of experimental research. Moreover, conducted tests, acquired results and their analysis could be a basis for future works on stabilizing system supporting the driver of an articulated tractor or enabling operation in remote control mode.

Abstract: Fuel cells and secondary batteries have both some disadvantages and advantages. However, looking closer at their characteristics, it can be concluded that in various aspects fuel cells and secondary batteries complement each other. Thus, combining these different electric energy sources to make one hybrid electricity source would allow using advantages of both sources and eliminating their disadvantages. In this article there are presented a comparative characteristic of PEM fuel cells and secondary batteries, their configuration of cooperation, and experimental results of their direct cooperation.

Abstract: The article is based on hypothesis that it is possible to establish the adequate joined mathematical model for ventilation of breathing space (for assessing of artificial breathing mixture real composition) and human decompression after breathing artificial hyperbaric atmosphere. In the effect of establishing mathematical model give the chance to understand gas exchange in human body exposed to pressure. It makes possible to plane extreme hyperbaric expositions (e.g. military special operations) and stimulates progress in the field of anaesthesiology. There is presented scientific project proposal.

Abstract: This article presents the author's dynamic model of power circulating gear test stand. It was assumed, that properly defined and next identified model can be used to analyze dynamic phenomena in meshing and bearings of gears and allows optimizing their construction, especially to minimize their vibroactivity. The article includes description of the construction of a test-stand, as well as short characteristic of the dynamic model. Afterwards it was presented verification, whether the model was correctly fine tuned. For verification purpose, were conducted laboratory measurements of velocity of transversal vibrations at the test-stand using laser vibrometer. Results of laboratory examinations were compared with the results achieved during computer simulation. Developed and presented dynamic model take into account a number of design, technological and operational parameters of gear. It was also presented algorithm of researches aimed at minimizing the vibroactivity of gear.

Abstract: Currently led military operations (Iraq and Afganistan) have shown that one of the biggest threats for vehicles moving in convoys are Improvised Explosive Devices. On the basis of experiments, it was found that there are not such structures which are completely resistant to explosion. The paper describes the concept for arms of suspension system with specially reduced construction node which undergo a controlled destruction at the time of detonation. Designing the target elements requires tests in order to determine the service load for suspension system..

Abstract: The paper presents some issues related to reliability model of a motorway telematics systems, in particular emergency communication system. Optical system architecture was presented and functions of the various subsystems, too. Analyzing the functional structure and method for transmitting information in a highway emergency communications system a method to calculate the reliability of the system was proposed. To assess the reliability of the emergency communication system, as a system repairable, availability index was also proposed.

Abstract: An influence of depth of the pits resulting from exposure to corrosive medium on the initiation of stress corrosion cracking process of AW 7020M (Rm=430MPa) alloy has been presented in the paper. The samples were subjected to several weeks of exposure to the solution simulating seawater, which resulted in uniform surface corrosion with the pits of depth from 30 to 100 μm. These samples were then subjected to a tensile test to determine their new properties (after the exposure). The tests have shown that the initiation of neck and cracking spot do not always coincide with the location of pits. The aim of this study was to estimate the minimum depth of pitting under the assumed shape, resulting in the initiation of cracking during the tensile test, using numerical simulations with the CAE software. The paper presents simulation results for the samples made of AW-7020 alloy of 3.75 mm thickness.

Abstract: The electromagnetic injector in the Common Rail system is the actuator directly responsible for fuel injection. Its proper operation is enabled by ensuring appropriately shaped changes of the electric signal worked out by the output stage of the controller. This paper determines the repeatability of the control signal and the possibility of using this signal for the diagnostics of the electrical part of the injector.

Abstract: The dissertation presents the method of controlling the designed scanning and tracking head (optical target seeker) [ which is used for detecting and tracking air targets emitting their own radiation, e.g. infrared radiation. The control algorithm consists in using the phase trajectories of control deviations. Digital simulations of the proposed solution have been conducted. The results of those simulations have been presented in a graphical form.