Acta Mechanica Slovaca, 2012 (vol. 16), issue 4
Simulation Model of Mobile Roboton whith Lengthwise Divided Chassis
František Trebuňa, Ľubica Miková
Acta Mechanica Slovaca 2012, 16(4):6-10 | DOI: 10.21496/ams.2012.034 
This article is about designing and constructing a four-wheel chassis. Analyzed is a used concept of chassis motion control of mechatronic systems on the principle of differential wheel control for the task of active tracking of planned chassis path. Created was a simulation model of chassis mobile system in terms of kinematics, which will be usable in concept of chassis locomotion control on diverse terrain. A model is also required for examining behavior of chassis on diverse terrain, for examining the influence of dimensions on chassis behavior during crossing over roughness of terrain.
Pitting Corrosion Investigation of Cantilever Beams Using F.E. Method
Jacob Nagler
Acta Mechanica Slovaca 2012, 16(4):12-20 | DOI: 10.21496/ams.2012.035
Carbon steel cantilever beams are widely used in many applications in aerospace, civil and mechanical engineering. Pitting corrosion is a phenomenon which places severe limitations on the design of such applications. As such, understanding this phenomenon and the methods to deal with it, are of a great importance. This paper presents numerical investigation by using F.E. (Finite Element) simulation on the load carrying capacity of corroded cantilever beams with pitting corrosion damage. The pitting corrosion hole shape has been modeled using ASTM G46 Standard Guide. Several different cases of pitting corrosion, represented by hemispherical holes, were...
Experimental Analysis of the Effect of Cutting Conditions on Microgeometry of the Machined Surface
Miroslav Badida, Miroslav Gombár, Lýdia Sobotová, Ján Kmec, Alena Vagaská
Acta Mechanica Slovaca 2012, 16(4):22-28 | DOI: 10.21496/ams.2012.036
Machining belongs to the basic and permanent manufacturing technology also on the present time, despite there was an idea (theoretical considering) in the publications of many experts in moulding and casting at the turn of the 70th and 80 years, that the machining could be replaced for the most part by accurate methods of casting or moulding. Although the material losses have been reduced in recent years due to approaching of components' size prepared by moulding or casting to the size desired by technical drawing, it is not possible to achieve the required accuracy of dimensions and shapes. The paper deals with statistical methods application to the...
Analysis of Water Pollution Indicators with the Use of Selected Statistical Methods
Barbara Ciecińska
Acta Mechanica Slovaca 2012, 16(4):30-33 | DOI: 10.21496/ams.2012.037
This article presents the problem of joining stainless steel which is used to produce various construction elements which are exposed to chemically active substances. Some traditional methods of joining sometimes are not possible to be put into use. The constructions cited here are frequently welded, however, investigated steel is not resistant to brittle failure after welding, thus it is not recommended for welding process. Adhesive bonding is suggested here as an effective method of joining elements of this material. Different methods of surface pretreatment were analysed before bonding with the use of several adhesives. Joints were tested for static...
The use of Rapid Prototyping technique in PhotoStress® method
Peter Frankovský, František Trebuňa, Mária Kenderová
Acta Mechanica Slovaca 2012, 16(4):34-40 | DOI: 10.21496/ams.2012.038
The subject of this paper is Rapid Prototyping method which is a widely expanding technique for quick and modern production of prototypes, models and tools by means of non-conventional technological procedures. The paper further presents the ways in which the technique can be used in PhotoStress® method. In the effort to speed up the whole process of product development it is crucial to select appropriate production technology. With conventional methods applied, the production of models is often expensive and, in a number of cases, ineffective. Therefore, new technologies such as Rapid Prototyping are coming into focus. These high-quality technologies...
Fully Coupled Thermo-Mechanical Analysis During Braking Process
Ali Belhocine, Mostefa Bouchetara
Acta Mechanica Slovaca 2012, 16(4):42-49 | DOI: 10.21496/ams.2012.039
The main purpose of this study is to analysis the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase. The simulation strategy is based on softawe ANSYS11. The modeling of transient temperature in the disk brake is actually used to identify the factor of geometric design of the disk to install the ventilation system in vehicles. The thermal-structural analysis is then used coupling to determine the deformation established and the Von Mises stresses in the disk, the contact pressure distribution in pads. The results are satisfactory compared to those found in the literature.
Conception of Contactless Strip Edge Guiding System on Continuous Galvanizing Line in U.S Steel Košice
František Trebuňa, František Menda
Acta Mechanica Slovaca 2012, 16(4):50-54 | DOI: 10.21496/ams.2012.040
The content of this work is the analysis of contact strip edge guiding system on Continuous galvanizing line CGL3 in the factory U. S. Steel Košice, s.r.o. The effort of increasing of the quality of production along with decreasing of costs involves replacement of contact system by contactless system. The aim is to present contactless strip edge sensor with appropriate electromechanic actuator. The right choice of components and adequate control of sensor movement achieves better strip galvanizing.
Hardness Variations on a Hydrogenated Tin Brass Heat Exchanger
Amjad Saleh El-Amoush
Acta Mechanica Slovaca 2012, 16(4):56-62 | DOI: 10.21496/ams.2012.041
Tin brass heat exchanger tube was hydrogen charged under different cathodic charging conditions. The introduction of charged hydrogen into tin brass tube was found to induce hardening on its surface. The severity and the depth of the hardened region was observed to increase with either cathodic current density or charging time. Ageing after charging results in either complete or partial recovery of hardness, depending on the charging conditions applied to heat exchanger tube.
Optimal Decision in Industry Choices
Jaroslav Rákoš
Acta Mechanica Slovaca 2012, 16(4):64-67 | DOI: 10.21496/ams.2012.042
The article gives one of the possibility of generalisation for optimal decissions about choices in robust industry systems. The task come from theory of fuzzy logic. Using all possible information about categories for choice in fuzzy systems there are possibility to transform the fuzzy decision to real sharp decission. The article describe the dependence of this sharpness on entropy of choice sets. The process has two or more phases and asked sharp result can get in spite of existence the high uncertainty at the end of choice. The method can take as universal procedure for different fieds of industry and other purphoses.
The Methodology of Application of Optically Sensitive Coatings in the Photoelastic Tests of Medical Models
Tomasz Kudasik, S. Miechowicz
Acta Mechanica Slovaca 2012, 16(4):68-74 | DOI: 10.21496/ams.2012.043
The article describes the methodology of applying optically sensitive coatings on medical models, e.g. the models of the upper skull and cranial syndesmosis. The article also lists all of the most important problems that may occur during this process and the methods of solving them. Also, the new approach towards applying optically sensitive coating on the cranial syndesmosis models is introduced. The correct application of the coating is one of the most important issues of the photoelastic research, as it leads to the proper determination of the stress distribution in complex elements of medical models, such as models of the upper part of human skull.
Efect of Hall Current and Slip Conditions on Heat and Mass Transfer of Unsteady MHD Flow of a Viscoelastic...
J.I. Oahimire, B.I. Olajuwon
Acta Mechanica Slovaca 2012, 16(4):76-86 | DOI: 10.21496/ams.2012.044
Heat and mass transfer effects on unsteady flow of a viscoelastic micropolar fluid over an infinite moving permeable plate in a saturated porous medium in the presence of a transverse magnetic field with Hall effect and slip conditions are studied.The governing system of partial differential equations is transformed to dimensionless equations using dimensionless variables. The dimensionless equations are then solved analytically using perturbation technique to obtain the expression for velocity, microrotation, temperature and concentration. With the help of graphs, the effects of the various important parameters entering into the problem on the velocity,...