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Global warming is a process in which the temperature of the entire planet gradually increases. High temperatures affect the surface of the material and cause undesirable effects such as damage because of overheating of the material. This article describes the use of reflective thermal insulation coatings on railway tracks abroad. Part of the article describes the method of applying reflective coatings to railway tracks. The article examines, analyzes, and evaluates the effect of a reflective thermal insulation coating on the railway track and railway wagon in the conditions of the Slovak Republic.

The safety of machinery is a very important aspect for its correct functioning in the conditions of modern production or assembly. According to the standards, manufacturers of special-purpose machines and devices are obliged to provide their equipment with a certificate of conformity (CE). This article describes the concerns of insufficient safety of a device. Insufficient coverage of part of the line meant that the certification did not take place, and the safety requirements were not met. The TRIZ method was used to resolve this technical discrepancy, providing designers with "instructions" on how to proceed, solve complex problems at the level of discrepancies and create solutions. By agreement of the designers, a solution that was not economically and implementation-intensive was created. All doors and windows within the fencing have been reinforced, thus achieving a greater degree of security. The resulting solution was subjected to simulations in the Ansys Workbench program, and the FEM analysis led to certain conclusions. The results were then moved to the structural engineer to assess the solution, who then approved the solution and successful certification of part of the device, respectively, in the assembly line.

Cycloidal (also called epicyclical or convex-concave) gears are used less often than common involute gears, which are very easy to manufacture and can be modified by corrections to the gear profile. Cycloidal gears are very sensitive to the proper axial distance between the pinion and the gear. The main advantage of convex-concave gears is the lowering of the contact pressure due to teeth flanks meshing and also the lowering of the slide ratios compared to involute gears. The calculation of the selected geometrical parameters and the contact pressure between the teeth flanks of the cycloidal gearing is described in the presented article.

This article presents a model of the geometry of teeth profiles based on the path of contact definition. The basic principles of the involute and convex−concave teeth profile generation are described. Due to the more difficult manufacturing of the convex−concave gear profile in comparison to the involute one, an application example was defined that suppressed this disadvantage, namely a planetary gearbox with plastic-injection-molded gears commonly used in vehicle back-view mirror positioners. The contact pressures and the slide ratios of the sun, planet, and ring gears with both teeth profile variants were observed and the differences between the calculated parameters are discussed.

This article presents a study of the amount of harmonic gear system backlash. The study shows a method for an effective measuring of the amount of backlash in harmonic gear systems. Given that this calculation tasks demand a lot of iterative operations, this article introduces a new method for creating 2D and 3D models of a harmonic gear system. At the same time, this study presents a new way of generating the geometry of a wave generator with a parametrically modified geometry. Introduction of the parametric model of a wave generator allows a rapid optimization of construction parameters, thus securing correct dimensioning and evaluation of the amount of backlash. When creating the computational model, operational characteristics were taken into consideration, therefore, the 2D and 3D computational models were created to correspond with real operation conditions to the greatest extent possible. The results of the analysis imply that the suggested method of examining the design parameters of the wave generator due to the harmonic gear system backlash is effective and correct. The benefit of this article is mainly to introduce a new dynamic computational model of a harmonic gear system and to optimize the construction parameters of the wave generator in line with the amount of backlash, which is manifested in the higher accuracy of the harmonic gear system. In the conclusion of this article we state our recommendations and acquired knowledge.

This article presents the correct adjustment of the mower’s blade movement relative to the forward movement of the mower. Everywhere around us are gardens, parks and meadow, which gives us reason to solve issues with mowing. The first part of this article shows agricultural machines, which are used today and the principle of correct cut of grass stalks. The next part shows the method of adjusting the mower’s blade speed. Design of a simple model was done with the use of Solid Edge Premium CAD. For computation, MSC Adams was used and post-processing was done with the use of Matlab. The connection between MSC Adams and Matlab was created by co-simulation.

This article deals with the kinematic analysis of trapezoidal suspension. Specifically, it focuses on the behaviour of the chassis when obstacle crossing was monitored. Our team is developing an autonomous mountain vehicle that will be equipped with different working adapters such as a cutter bar and a picker. The device was designed for work on slopes, hence, must be able to overcome certain natural obstacles. This implies the need to analyse the wheel suspension kinematics. The vehicle was built on a trapezoidal suspension, which has proven to be the most suitable option with respect to operating conditions. From the results obtained, it was possible to analyse the driving characteristics of the obstacle, track the rollover limits and overall safety of operation.