Acta Mechanica Slovaca, 2025 (vol. 29), issue 1
Orbital Analysis of a Breathing Cracked Rotor During its Passage Through the Subcritical Speeds
Otmane Zerrouki, Ahmed Fellah, Ahmed Saimi
Acta Mechanica Slovaca 2025, 29(1):6-12 | DOI: 10.21496/ams.2025.006 
In the present paper, an orbital analysis is conducted to study the effect of a transverse breathing crack on the orbits of the rotor during its passage through the subcritical speeds; this study makes it possible to predict the presence of cracks in rotors. The classical version of the finite element method is used to model the rotor. While, the equation of motion is obtained by the application of the Lagrange equation on the kinetic and deformation energies of the different components of the rotor taking into account the variation of the shaft's stiffness due to the crack, The results are obtained using a Matlab code based on Newmark's beta method,...
Use of Gaming Engines for Robotic Simulations and Computer Vision
Leo Brada, Marek Málik, Erik Prada, Ľubica Miková
Acta Mechanica Slovaca 2025, 29(1):14-20 | DOI: 10.21496/ams.2025.007
Gaming engines have evolved beyond their traditional role in entertainment, becoming powerful tools for robotic simulations and computer vision applications. Their ability to generate high-fidelity, real-time simulations makes them valuable for developing and testing robotic systems in virtual environments. The experiment demonstrated the use of the Unreal Engine, and its computer vision plugin called UnrealCV. A realistic factory environment was created in order to test the capability of the computer vision plugin. The article evaluates UnrealCV and its features along with their potential use in future work. Data from depth cameras are visualized...
Detection of Straightness Deviation on a Production Machine in an Automatic Cycle
Artur Zawada, Mateusz Markiefka
Acta Mechanica Slovaca 2025, 29(1):22-27 | DOI: 10.21496/ams.2025.008
The article presents a method of measuring straightness of a metal flat bar on a production machine in an automatic cycle. The measurement was carried out while the production machine was operating, using a laser profilometer. In order to determine straightness, the measurement results were used along the entire length, the maximum deviation was calculated and presented, defining whether the measured part meets production requirements.
Coupling DRNN with Numerical Simulations for the Thermal Performance Analysis of a Shell-and-Tube Heat Exchanger Using Cu/Water Nanofluid
Bouhelal Guendouz, Hamidou Benzenine, Mohammed Beldjilali, Kaddour Bahram, Rachid Saim
Acta Mechanica Slovaca 2025, 29(1):28-35 | DOI: 10.21496/ams.2025.009
This study investigates the thermal performance of a shell-and-tube heat exchanger, enhanced by using a Cu-water nanofluid on the shell side. A combined experimental and numerical approach was used to assess the effects of varying nanoparticle concentrations (2% to 6%) and cold-side flow rates (0.047 to 4 l/min). At 6% concentration, results showed a temperature increase of up to 7 °C on the shell side, a 12% improvement in thermal efficiency, and a global heat transfer coefficient reaching 8516.87 W, compared to pure water. Additionally, a deep recurrent neural network (DRNN) was implemented to predict key performance indicators: thermal efficiency,...
Influence of Environmental Factors on Sleep Quality: Analyzing Light Exposure and Sleep Duration with Smartwatch Data
Veronika Sedláková, Radovan Hudák, Peter Kneppo, Dominik Hakulin
Acta Mechanica Slovaca 2025, 29(1):36-43 | DOI: 10.21496/ams.2025.010
Artificial lighting significantly influences circadian rhythms and sleep quality. This case study investigates the impact of environmental factors including temperature, relative humidity, CO₂ concentration, total volatile organic compounds (TVOC) and exposure to different light spectra on light sleep duration in a single subject. Sleep data were collected using a Xiaomi Mi Band 6 smart wristband, while environmental parameters were monitored with a custom Arduino-based sensor system. The results indicate that the optimal temperature for light sleep ranges between 17 and 21 °C, with the longest light sleep recorded at approximately 18 °C. Humidity,...
A Pilot Study on 3D-Printed Impression Trays for Cleft Palate: A Digital Manufacturing Approach
Natália Savková, Branko Štefanovič, Marek Schnitzer, Juraj Bánovčin, Jozef Živčák
Acta Mechanica Slovaca 2025, 29(1):44-48 | DOI: 10.21496/ams.2025.011
Cleft lip and palate (CLP), affect approximately 1 in 756 births and require comprehensive, individualized treatment strategies. Among the first important interventions is the creation of impression trays for nasoalveolar molding (NAM) plates, which help separate the oral and nasal cavities in newborns. However, traditional tray fabrication methods are labour-intensive, imprecise, and unsuitable for mass production. This study investigates the use of reverse engineering and additive manufacturing (3D printing) to streamline and enhance the production of CLP impression trays. Seventeen tray models were digitally designed using 3D scanning and computer-aided...
Internet of Things in the Context of Digital Online Revolution in Marketing of Bosch Campaign LikeABosch
Zuzana Dzilská, František Pollák
Acta Mechanica Slovaca 2025, 29(1):50-57 | DOI: 10.21496/ams.2025.012
The Internet of Things (IoT) is fundamentally changing our everyday lives. It contributes to improving the quality and prosperity of life. This study aims to analyse the change that technology brings to daily life and on analysing the IoT marketing media campaign LikeABosch between the years 2019 and 2023 within the geographical territory of Brazil, China, France, Germany, India, UK and USA. The study methodology includes collection of secondary data available at the annual Tech Compass Survey. In 2019 Bosch published a campaign LikeABosch promoting Bosch IoT products. Based on the number of views of the media campaign on youtube.com under the brand...
Study of Damage in Woven Composite Materials Subjected to Impact
M. Djilali Beida, Habib Achache, Rachid Zahi
Acta Mechanica Slovaca 2025, 29(1):58-62 | DOI: 10.21496/ams.2024.027
This study focuses on modeling the low-velocity impact behaviour of textile-shaped composites. Textile preforms are modeled using Texgen software. Six types of fabrics are considered: Twill (2/2) [0]4, twill (2/2) sequence [0/30/-30/0], twill (2/2) sequence [0/45/-45/0], and plain weave [0]4, plain weave sequence [0/30/-30/0], plain weave sequence [0/45/-45/0]. For the study of fabric damage under impact, the commercial finite element software Ls-dyna is used in transient regime. The "automatic-surface to-surface" approach is employed to model the contact between the impactor and the laminate, while the contact between fibres and the matrix is modeled...