The presented article presents an innovative solution of a fire-fighting adapter based on the basic hypothesis: to provide sufficient technical support in difficult terrain conditions for water transport logistics in order to quickly prevent the spread and destruction of forest fire. At present, when forest fires begin, it is often quite complicated to provide sufficient technical support for the quick prevention and elimination of fires. This fact is largely eliminated by the designed fire-fighting adapter. The mentioned fire-fighting adapter can be used as a fire-fighting mobile device with a base machine of a forest wheeled skidder (LKT), part of the long-distance transport of water in difficult terrain (lake system), a water tank in difficult terrain with the possibility of filling the Bambi bag with a helicopter, part of the long-distance transport of water in the case of a difficult water source without a forest access road network, and a mobile device for emergency transportation of materials in difficult terrain. In addition to the use for fighting forest fires, the fire adapter can also be used to provide for transport of water for forest nurseries (irrigation), freshly planted areas in the event of prolonged drought, the filling of watering-places for forest animals and filling puddles in the dry season. When designing the supporting frame, we used and imitated the evolutionary approach of nature in the form of generative design. The presented paper deals with the use of modern composite materials in the design of superstructures for base machines, which gradually acquire meaning. The main reason for the increasing use of fiberglass is to achieve higher strength and safer weight reduction. This adapter is designed for forest wheel tractors that reach 40% slope availability, are able to work on the stand area, overcome obstacles and are available in sufficient quantities in all Slovak forest areas.

The article dealt with the assessment of the quality of hydraulic oil and determination of the mode of wear of the friction surfaces of Baljer & Zembrod manipulating lines through the information traces in the oils by applying tribotechnical diagnostics. We presented the assessment of the level of degradation of the oils. In addition, we presented the mode of wear of the friction surfaces washed in oil through evaluation of the qualitative and quantitative characteristics of the particles found in the oil. In detail, we focused on the application of suitable multivariate statistical methods on the data matrix. The article also presents predictive models that can sort oils into groups based on the assessment of quality of the oil and the state of the friction couples. The models can be used in research and in solving practical tasks in tribotechnical diagnostics of hydraulic fluids in woodworking equipment. Our results showed that the manipulation lines were greatly thermically stressed due to inadequate oil and machine maintenance. By correlative integration of all methods used, we could determine the real mode of the wear of the tribologic nodes of the machine. The experiment enabled the early detection of an undesirable process in the tribological node and implementation of corrective measures before the machine would break down.

The article is focused on the static stability of a vehicle with a 2000-liter water tank behind the rear axle. The purpose of the research is to evaluate the influence of the tank on stability. The vehicle is composed of a forestry skidder, a water tank, and equipment. To equilibrate the tank a ballast weight of 500 kg in front of the skidder is used. The influence of various combinations of the full water tank, half-filled water tank, and ballast weight is evaluated. The stability is determined as the distances of vectors of a stability triangle and a gravity vector, that is placed in a center of gravity of the whole vehicle. A Python programming language is used to implement the solution. The results are displayed in form of heatmaps. For the analyses, a slope angle of ${18}^{\circ }$ is used. The results show that the longitudinal stability is decreased and lateral stability is increased. The tank also makes the vehicle unstable in some positions.

Large-format additive manufacturing is a candidate for tremendous savings in terms of time and cost while simultaneously enabling higher flexibility, quality, and variability. Most of the design constraints of small-scale polymer 3D printers still apply to large-format additive manufacturing. The paper details both the strengths and deformation-related design considerations for additive manufacturing to gain a better understanding of the material capabilities and limitations, mechanical characteristics, and how to use them for large-format additive manufacturing (LFAM). The results show that the tested materials for additive manufacturing meet the requirements from the stress and deformation points of view. Compared to the steel and composite material, the strength limits are lower, but high enough for the given load. The materials HI TEMP, HI TEMP CF, PA12CF, PA6/66, and PLA seem to be the most promising for LFAM to create a firefighting water tank. The results may be considered as an introduction to further research that should lead to real solutions for the production of atypical tanks.