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Railway line capacity is growing in importance as a criterion for the assessment of railroad infrastructure performance. This problem is becoming more and more relevant as the demand for rail transport increases, especially considering the transport policy related to the promotion of climate-neutral means of transport. Insufficient capacity affects the stability and reliability of railway traffic operations. The analytical methods used for capacity estimation are typically insufficient to solve problems of a multicriteria nature (i.e. problems which take traffic heterogeneity and human factors into account). Optimisation methods, on the other hand, usually yield the best results if the current timetable for a given line is known. Additionally, they do not strongly consider the impact of the running characteristics of a specific train type and of the system or several systems in operation on the line (e.g. national Class B system and ERTMS/ETCS system). Therefore, this paper proposes a model and a simulation program developed in the Matlab and Simulink environment to be used to simulate on-route train movement, to study railroad capacity with different control systems, as well as for predictive train control to minimise energy losses. The authors described the assumptions adopted for the simulation program and the input parameters configurable against a specific line segment. They also discussed selected results derived from simulations of controlling the departure of trains to a railway line with the purpose of energy loss reduction.

The article provides a discussion on a methodology intended for testing of power transmission systems featuring an innovative highly torsionally flexible metal clutch patented by the co-authors of this paper. What this methodology takes into account is the amplitude and frequency analyses discussed in the article, as well as a sensing system based on diverse piezoelectric and magnetic phenomena, the Doppler effect, etc. Both contact and non-contact (laser measurement) methods were used during the tests. The purpose of the tests conducted at the stand, originally designed by the authors in accordance with the methodology proposed, was to evidence that using the innovative and patented, highly torsionally flexible metal clutch makes it possible to reduce the vibrations of multi-stage toothed gears, consequently reducing the forces affecting the gear bearings and those acting at the tooth space, which is to enable the service life of individual components of the power transmission systems intended for mining scraper conveyors to be significantly extended. Based on the studies and analyses performed by the authors, one can observe and conclude that the methodology proposed in the paper makes it possible to use an example of a relatively complex power transmission system in order to examine the relationships between the processes at work, i.e., the decline of the linear vibrations of the gear housing (which is undoubtedly positive in power transmission systems) at the expense of increasing torsional vibrations of the innovative clutch, the latter not to be considered unfavourable to users in the case analysed.

Regeneration of parts is the most correct form of use of worn out components and contributes, among others, to reduce CO2 emissions. In the case of elements of fuel injector systems, very high precision is required and such regeneration should be carried out using the original parts. It also requires testing on the original testing stands of these manufacturers, which very often characterized by the fact that it is not possible to perform a short test, which means that it is only possible to perform a time-consuming comprehensive test. An unquestionable advantage in some cases would be the possibility of preliminary verification of the correct operation of the regenerated subassembly without the need for a full time-consuming test. In the present situation, only after completing a time-consuming comprehensive test of the diagnosed element of the injection system, it is often necessary to carry out its disassembly, replacement or correction of one of the components and reassembly with the next time-consuming test. In the case of low unemployment in the labour market, this is extremely unfavourable, and it is often not possible to organize work in such a way that the diagnostic test of the subassembly takes place without the participation of an employee. On the basis of the analyses presented in this article, carried out in the research and development department in company whose employee is one of the co-authors, it can be stated that in the current situation on the labour market where skilled workers are required to work and for the development of science is the most purposeful recognition of the possibility of using vibroacoustic signals to shorten time of tests, which with a high probability may end in a negative result. The preliminary analysis carried out, show that limitation of diagnostic time can be over 35%.

The paper presents how an important aspect of introducing new machines, especially in the mining industry, is testing a prototype under laboratory conditions. For this purpose, advanced methods of analyzing the vibrations of a drive system equipped with an innovative prototype of a flexible torsion clutch are presented. The main goal is to present a comprehensive method for analyzing vibration signals in various dimensions of the signal analysis. As a result of this approach, it can be seen how much important information about the tested clutch can be obtained by using various analysis methods in terms of time–frequency distributions or order analysis. To emphasize the differences in the functioning of the tested clutch and the possibility of monitoring these differences on the basis of the observation of residual processes, such as vibrations, the results for the flexible and locked clutch are compared.

In this paper authors carried out research, while modified gear fixing was used to limit the vibrations of the gearbox with non-parallel shaft axes. For tests modified back-to-back test stand was used. During test gearbox worked without load, with various rotational frequency and value of non-parallelism of shafts axes. Analysis of the obtained results presents that only in some cases the use of modified fixing of gear causes a reduction of the measured vibrations.

The subject of the experimental research was a modified back-to-back test stand. During the test, the driven gear with a number of teeth z1=16 was fixed on stationary axis. The tested gearbox worked without load and the closing gearbox was dismantled to avoid any additional vibration and noise. A mechanical system was also used which, during the tests, allowed to change the position of the above mentioned stationary axis. Gear with number of teeth z1 was fixed on a stationary axis with the arrangement of two self-aligning ball bear-ings which prevented significant changes in the angular position of axis of gear in regard of stationary axis; or fixed on a stationary axis with the arrangement of one self-aligning ball bearing which allowed significant changes in the angular position of axis of gear in regard of stationary axis. On the basis of the conducted studies, it can be stated that only in some of the analyzed cases fixing of gear with the arrangement of one self-aligning ball bearing reduces the vibration of the gearbox elements.