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Optimization is the process of finding the best possible solutions of a problem. It has been widely used in various areas especially in engineering problems. One of the common issues that is faced by some of manufacturers is finding drilling sequences of multiple holes. By drilling multiple holes with the least total path length, the manufacturer can save a lot of time and it can increase the productivity of the company. Thus, this study focuses on drilling path of multiple holes problem which has been solved by other researchers. This study uses the Bees Algorithm to find the best sequence of drilling holes (mini-mum total path length) and the results found are compared with the result of other algorithms. In addi-tion to results comparison with other algorithms, the results obtained are verified with simulation results using MasterCAM software. The results comparison shows that the Bees Algorithm achieved compara-ble performance compared to other algorithms.

The article deals with the use of SPC tools to manage and improve the machining process - drilling furniture elements. The content of the article is to use such SPC tools as basic statistical parameters, box plot, histogram, classic and special control charts, and process capability indicators to assess the drill-ing process and to indicate areas to improve. The article indicates the power of SPC tools in woodwork furniture process control and power of using the Statistica program from TIBCO Software Inc. in this area. SPC tools bring a lot of important and useful information about the analyzed drilling process, its weaknesses, which contributes to the improvement of the process. The conducted study has been shown that the tested drilling process requires improvements, in particular in the area related to the machine and man. The activities that should be implemented to improve the quality of the process were defined, including implementation of the Poka-Yoke system, development of a maintenance inspection schedule, a visual manual for machine setup, employee training with a verification exam, introduction of an employee's suggestion system, modification of the company's motivation system. SPC tools helped to identify the source of process problems, defined a process’s stability and capability to meet a customer requirement, and assist with other insights, that were used to define improvement action.

The topic of the article is to compare the mechanical properties and define the differences in the degra-dation process for anticorrosive glass fibres type AR and for glass fibres type E after influence of the alkaline environment in the geopolymer composite. The ongoing reactions between glass fibres and al-kaline environment lead to the dissolution and slowly decomposition of the fibres and consequently to the loss of the mechanical properties of the composite. Corrosion of glass fibres is characterized by weight loss, change of fibre diameter, reduction of mechanical properties and formation of mineral in-crustations on the surface of the fibre, which gradually leads to the formation of a continuous corrosion coating so called corrosion shell. Scanning electron microscopy was used to monitor the morphology of the fiber surface, and image analysis methods were used to evaluate morphological changes. Tests of mechanical properties (fibers - tensile test, composite materials - three-point bending and Charpy test) were used to confirm ongoing degradation processes due to the long-term influence of the alkaline envi-ronment on both types of glass fibers.

This paper deals with the topographic evaluation of samples made from materials applied in biomedicine. Different samples were made from Ti, TiAlV, TiNb and austenitic steel – Fe were used together with different surface morphology created. These samples were coated with a layer of TiNb alloy. The goal was to measure surface roughness in individual samples of biomaterials and to evaluate a 3D measurement of surface morphology made with a confocal microscope. Another task was to compare with appropriate software the pictures of material topography acquired at lower and higher magnification. Lower (10x) and higher (200x) magnification was used. For measured data evaluation SPIP and Gwyddion software were used. The same method of surface treatment was used but on different samples, which can lead to different results. The values obtained from topography measurements are crucial, but their formulation or evaluation can be affected by different processing methods. Our interest was to find and record the theoretically best procedure for the evaluation of measured data. Then to better understand the cell adhesion and integration of bacteria, we dealt with visualization of topography of given samples.

The article describes problems of welding heterogeneous welds be specific of heat resistant steel X15CrNiSi20-25 with cobalt alloy Stellite 6. Heterogeneous welds are produced by GTAW (141 according to standard EN ISO 4063) welding method. The major goals of the experiment were performing preliminary welding specifications (pWPS) for a specific welded part. Further was necessary for this weldment set parameters on mechanical testing.

The article is devoted to a comprehensive analysis of the coating of a component from the Ford Fo-cus 1.0 l EcoBoost engine. It is one of a pair of materially identical aluminum gears connected by a drive pulley and a drive. Aluminum gear components are surface treated with a mixture of metal powders using PVD technology, where the goal of the coating is to increase the hardness, abrasion resistance and heat of the base material. The chemical composition of the basic material of the gea-red aluminum drive wheel of the FORD engine proves that it is a component made by thermofor-ming and corresponds to the alloy EN AW 6061 (AlMg1SiCu) according to the standard ČSN EN 573 1-3. The microstructure of the base material component exhibits fine intermetallic phases evenly dis-tributed throughout the cross-section of the base base material, without the occurrence of larger inc-lusions and/or porosity. The cross-sectional microstructure in the area of the coating demonstrates that the component has a continuous uniform surface layer of the coating formed without a defect and does not have a diffuse bond with the base material. The measurement of the coating thickness of the component shows a continuous surface layer formed by powder metallography, which ranges from 70.1 µm to 143.9 µm. The surface EDS of the surface proves that it consists of deposited tungsten carbides produced by powder metallography and the bonding material is cobalt. Area EDS analysis of the surface coating identified morphologically two distinct areas of dark and light, where tungsten carbides and cobalt are based, and only the tungsten carbide and cobalt carbide contents change. The oxygen and carbon content also changes in the dark and light areas.

The article presents new possibilities of simulation software and its application to improve the pro-duction structure. In many enterprises, the basic issues are related to the determination of planned tasks for individual positions, calculating the demand for employees, taking into account their skills and qualifications, calculating work costs, determining work efficiency and its dynamics. Therefore proper work organization consists in setting the course of work in such a way as to obtain maximum results with the least amount of work by man and machine. The article presents the problem of per-sonnel allocation to the production line. The basic stages of developing a simulation model of this process are discussed, including all necessary information and inputs. The results shows impact of the selected simulation scenarios to the workload level of the staff and the duration of the production process. In this concept, to solve the problem a simulation model of the production process was built. A new generation of 3D FlexSim simulation environment with an integrated OptQuest optimi-zation module was used.

Very dynamic development in the field of computerization and industry robotization, as well as an im-plementation of the Industry 4.0 assumptions are the main reason for the increased demand for magnetic materials. The limited rare earths availability and the sustainable development in the field of material engineering indicate that the methods of recycling magnetic materials from Waste of Electrical and Electronic Equipment are necessary. This paper presents the impovement stages of magnets recovery process - extrusion process of magnetic scraps/particles with polymer (magnetic scraps and particles obtained from WEEE). The process is developed based on the Process Failure Mode and Effects Analy-sis. The reserch pointed the irregularities, that pose the greatest risk of failure in the process. The paper presents changes in the process based on the values of the indicators: severity (S), probability of occur-rence (O), probability of detection (D) and the Risk Performance Number (RPN). Based on the PFMEA, 5 operations were added to the process. Due to changes in the process course, it is possible to minimize the effects of the irregularities occurrence.

Marine ships engines are kind of huge diesel engines. In fact, the manner of controlling the speed of a ship can impact badly on the financial matters of the machinery operation. Thus, controlling the speed of the marine engines can avoid ships to face dangerous accidents. In purpose to prevent such kind of damages, marine systems simulator have been widely used as numerical tools. In fact, the simulation of speed control systems makes it possible to render the process of controlling the speed of an engine economical and eliminates many risks. In this article, we first present a mathematical formulation to illustrate the rotational velocity process of a ship model's marine diesel engine as well as its PID controller. Secondly, we introduce a novel python's marine simulator which includes a PID controller to govern marine ship model's engines and we compare its results with another PID diesel engine speed controller that we modelled, designed and simulated via Matlab/Simulink. Results of scenarios and experiences which we carried out have shown that the response of the speed control system when using python can be accurate and close to the one of Matlab/Simulink.

CFRP (Carbon Fiber Reinforced Polymers) are often used when designing parts that need to be stiff, light and thermally stable. These benefits are a big motivation to use CFRP in many applications, one of them could be sports optics. However, optical devices require precise dimensions with tight tolerances for the opti-cal assembly to work correctly. In order to determine if CFRP could be a suitable material of choice for sports optics a simplified body of binoculars was designed. The main purpose of this prototype was to prove the possibility of using CFRP in binoculars. The tubular body was manufactured by prepreg lay-up into a 3D printed mold, followed by curing in an autoclave. After the prototype was manufactured 3D measurements of the tube using 3D scanner GOM ATOS were made. As expected, shrinkage of the mold and the epoxy resin in the matrix of CFRP caused minor deformations. However, if the shape of the cured part remains unchanged during conditions similar to the general use of binoculars, then the initial deformations happening during manufacturing could be accoun-ted for when designing the part. Other than the carbon part itself, the bond between metal and composite components is another potential point of failure in terms of desired precision. Because of that measurements and tests of concentricity of ad-hesive joints are being currently performed. The results of these tests and others that will follow will indicate if composite materials could be used as a structural material for sports optics.

This paper deals with the comparison of two tool steels M390 and M398 produced by powder metallurgy of the MICROCLEAN type. The primary use of steel is in the plastics industry to produce screws for injection moulding machines. The main purpose of the paper is to analyze the hardness after different stages of heat treatment. The first part of the article evaluates the hardness of steels after hardening, which was performed using a hardening dilatometer DIL805A. A total of 8 different controlled cooling measurements were performed, for both types of powdered tool steels, from a maximum rate of 100 °C/s to a minimum of 0.01 ° C/s. Based on the results of the first set of samples from the hardening dilatometer, the optimal cooling time is evaluated to achieve the highest hardness of both materials. This rate was used to heat treat a second set of samples that had undergone a quenching process from which a selected group was quenched to -78 °C. Freezing was performed to reduce the amount of residual austenite. Before measuring the hardness, the samples were tempered at temperatures of 200, 400, 600 °C for 2x2h. The measured hardness values were then compared with data from the manufacturer BÖHLER.

The aim of this paper is an analysis of the dependability of critical components of the John Deer 7530 tractor. For this analysis data was used from a database which contains maintenance data of 166 trac-tors during approx 9 years. The first part of this article is devoted to the selection of critical compo-nents based on number of failures of individual machine parts for a given period and their sales pric-es. The next part of article presents data for calculation dependability indicators which contains oper-ating times to failure and operating times without failure. Due to the large size of the data files of the individual components, the data are only given for one machine component. Furthermore, the meth-od of calculation of dependability indicators is described by parametric statistical methods according to ČSN EN 61649:2009 and mean time to operating failure. The results of the analysis are summa-rized in tables and graphs. The method in this article can be used to optimise the maintenance pro-gram.

In the last decades, advanced brake technology in the port sector follows the global productivity developments of the international maritime trade. Container vessels are getting bigger and bigger and the ship to shore cranes is getting consistently higher. But service, emergency or storm brakes cannot be getting bigger and bigger to meet these increasing demands. Throughout history, innovations and advancements in technology have made industry better through automation and increased efficiency. No matter how advanced industry becomes, the need for emergency duty stopping brakes will not go out of style because there are always circumstances that require mechanical brakes to do the job. Brakes will invariably insure against those rare, yet potentially catastrophic events that even modern technology cannot defend against.

Trusses are commonly used structure in industrial buildings, warehouses, bridges, transmission tower etc. The analysis of the truss structure design is necessary in order to ensure stable and economical system. This paper presents application for computing planar truss structures that was programmed in environment of MATLAB App Designer using finite element method (FEM). App Designer is programming environment used for creating computing applications with graphical user interface (GUI). The created application for trusses allows users to create geometrical model of the truss structure and input material data, perform static analysis, modal analysis and to optimize truss structure in order to minimize its weight. To ensure accuracy of results, test calculations was performed using commercial software and compared with results from the created application.

The aim of the article is to compare the experimental investigation of deflection of the sandwich composite beam with theoretical models. The experimental test specimens were composed of three layers. Skins were made using epoxy-resin-impregnated glass laminates with plain weave. The light weight foam Divinycell H100 was used as sandwich core. The three-point bending test was carried out. Fibre-optic strain gauges, SOFO SMARTape Compact deformation sensors, were used for determining the deflection of the sandwich composite structure. Experimentally obtained data were used for comparison with theoretical models – sandwich theory with the transverse shear, sandwich theory without the transverse shear, laminate theory with the transverse shear and laminate theory without the transverse shear.

Generative design is one of the most promising means of new product development in the world. It allows formation of organic structures that brings various benefits, e.g. in the form of savings of material and production costs. Generative design includes several types of technology, topological optimization included. The paper addresses the technology of topological optimization implemented on the support part of the 3D printing pad. The result of optimization is the creation of a new, more suitable design concept through the Altair Inspire optimization software.

Grinding is one of the basic finishing operations which can be used for parts made from different materials where high quality and surface accuracy is required. One of these materials is maraging steel 1.2709, which is used for the test samples for tensile testing. In this case, it is very important to achieve good surface quality. Wear of a grinding wheel is best expressed as G-ratio which shows us if the grinding parameters are selected correctly. This article deals with the influence of grinding conditions and grinding wheels on surface roughness and wear of the grinding wheels when grinding tool steel VACO 180 on a 5-axis grinding machine. The experiment was designed to investigate the influence of changes in cutting speed, depth of cut and using two different grinding wheels for these two values. At the end of the article, the results from the experiment are summarized and compared.

Prototype production is a key element in the process of developing a new product. The prototype is important both for the initial materialization of ideas and intentions for product design, as well as for subsequent assessment of the technological design of this design. 3D printing technology is also used today as a suitable technology for prototype production, especially for the possibility of relatively rapid adaptation to complex shape geometries, the ability to produce what would be difficult or impossible to produce with conventional technologies, and last but not least, the increasing availability of 3D printing equipment.This paper demonstrates the principle of production of auxiliary gauges, for checking the dimensions of a prototype product with complex shape, 3D printing and its further possible use in the conditions of an engineering company. The conclusions of the paper should show the possibility and suitability of integration of modern and classical production technologies in the conditions of piece or custom production.

The aim of the paper is to introduce the digital twin concept as part of the Industry 4.0 strategy. In the form of a case study, the procedure and outputs of the simulation of a specific production plant to-gether with its intermediate storage and output for the next plant are presented. In the research part is presented a simulation model of production lines and intermediate stock with material flow represen-tation. At the beginning of the research the analysis of production and logistics processes was carried out. The next part describes the programming methods used to record and redirect material flows between individual lines and stock. The simulation method using simulated production line models enables the digitization of dynamic production processes in enterprises. We expect that in the coming years there will be an increase in demand for the creation of simulation models of production systems in modern manufacturing companies that will try to implement the Industry 4.0 strategy and thus in-crease their competitiveness.

The article deals with the evaluation of interactions between abrasive particles and treated sample surfaces. It represents a summary of the knowledge gained from research the wear of tools for crushing unwanted growths. Samples of materials were tested under laboratory conditions. The hardness of HRC and HV10 was evaluated in the experiment, abrasive wear rate, assessed according to standard GOST 23.208-79. The depth of the track under test disc by using silicon abrasive particles was also evaluated. Furthermore, the hardness coefficient KT relative to the base material of the tool - 16MnCr5 steel and the hardness of abrasive were determined. By comparing the measured and calculated values the heat treatment procedures and hardfacing materials were assessment. By comparing the measured and calculated values the heat treatment procedures and hardfacing materials were as-sessment, which are expected to provide an increase the abrasion resistance towards to an abrasive, heterogeneous working environment in operation.

This work was focused on the research of the different variability production deep-drawing sheets made of AlMg3 alloy which could influence on their deep-drawing properties e.g. non alloying elements Fe, Mn, heat treatment parameters and structure with aim to judge ascertained and analyzed properties of the sheets. The mechanical properties, mainly the highest elongation, and the other parameters (grain size, metallurgical purity), were measured due to they had had the main influence on the deep-drawing properties of the sheets made of AlMg3 alloy. For this research work had been obtained 5 deep-drawing sheets made of AlMg3 alloy with different production than chemical composition and heat treatment with the aim to realized ?complex analyze?, and to find up the best variant for production technology with the high deep-drawing properties.

The objective of this paper was to investigate and respond to the quality and strength of CMT welds that were sub-jected to degradation effects and subsequently to tensile testing. The tensile test was recorded using AE acoustic emission. The experiment focused on the quality of CMT welds (Cold Metal Transfer) and the resistance of these welds to corrosion degradation. Welds are generally exposed to environmental influences such as high stress, stress and degradation effects. The combined effect of these factors may in some cases result in the destruction of weld joints. For this reason, emphasis is placed on the quality of welds and their resistance to environmental influ-ences. For this measurement there were ten samples prepared, divided into two groups, each having five samples. One group was subjected to corrosion degradation, while the other one was at the same time subjected only to envi-ronmental influences. Subsequently, all samples were subjected to tensile testing. The course of this test was rec-orded using the AE acoustic emission, where the AE sensor was attached to each weldment to record dislocations during the tensile test. Named values were evaluated in the Dakel–Daeshow program.

Modern production systems requires high effectivity and flexibility with always increasing demands for precision as an imperative for more efficient components. The same apply for quality inspection providing data for feedback regu-lation of production processes. CMMs (coordinate measuring machines) which are flexible and universal in use yet very accurate and easy to automate are a standard mean for quality inspection. With many sensors available on the market, central fixed scanning heads with tactile scanning probes are a reference equipment for inspection of precise production of engine and transmission components. Tactile probes are right choice where very high accuracies and stability of results is required. Effectivity was allways a target in production processes and today the same pressure for effectivity and productivity is required from measuring machines, yet measurement strategies are often taken from measurement plans even 10 years old. This means that in old programs low scan speeds are used based on capability of older technologies and the approach of don´t change it when it works is common. This limits productivity of the whole quality control process. Motivation for this paper and whole research is to increase productivity and thus capaci-ty of quliaty inspection without compromising process capability. Lack of measuring capacity is usually solved by purchase of a new machine which may not be allways necessary. Primary motivation of companies supplying these technologies is not maximum efficiency of quality inspection, which in context of spare capacities ultimately means lower sales. Aim of this article is to describe influence of scanning speed and size of inspected feature on CMMs accu-racy. High-precision CMM control itself is not easy because with decreasing path radius dynamic effects of machine construction itself increase on measurement results. Accuracy of CMM measurement is then function of feature size being checked. This knowledge can be used for optimization of measurement plans in terms of productivity while maintaining sufficient measurement accuracy depending on required tolerance.

This article deals with optimization of the truss structure. A genetic algorithm is used for this optimization. Within the strength calculation of the truss structure a normative assessment of the beam and their buckling stability is implemented. Also, the entire calculation is designed to use only standard profiles. In the first task, the optimization is focused on the weight of the structure, and in the second, on its price. There are also developments using different population sizes for individual cases, which will be described below. At the end of the work, a hypothesis is made for the link between price optimization and weight reduction.

This template describes the behavior of products created with additive 3D printing technology. The tested material used to produce the samples was polyactide acid (PLA). PLA is one of the most favourite material for 3D printing. This polylactide acid contains a metal additive. The standard dog-bone shaped samples reinforced with internal ribs arranged in a grid with 20% of the internal volume of the rib-filled sample were tested for tensile strength. The samples were subjected to different types of chemical degradation prior to the test. As a degradation agent, there was used an organic solvents. The result of the research is the effect of the degradation factor on the mechan-ical properties of these samples and possible use in practice, specifically in technology.

This research focusing on influencing the surface structure and its geometric deviations from the CAD model after various tumbling of bodies at constant parameters of the tumbling machine. The purpose of determining the actual effect on the resulting surface before and after the tumbling pro-cess, which tumbling body causes the selection of a larger grain or compaction of the surface layer. The research outputs are thermographic maps and geometric deviations measured using CAD mod-els. The experimental line was at VŠB - TU Ostrava, with the help of the PROTOLAB 3D printing center, there was an experimental sample in your game. Measurement of access in the metrology laboratory on CMM Wenzel LH 65 X3Premium and optical heads Shapetracer II.

During the last years, due to the dynamic development of the non-contact measurement methods, there has been observed still increasing number of their applications in various fields - not only in the engineering industry. E.g. from the dimensional quality point of view, knowledge of real 3D data of a given part is truly very important. There are several options for obtaining these data such as the usage of optical 3D digitization or computed tomography (CT). However, within the mutual comparability of such data, it is very important to know not only the accuracy of acquiring 3D data, but also e.g. possibilities of these systems in terms of own measurement. In the paper, a specially designed part containing various convex and concave shapes was measured by using two different systems (ATOS TripleScan optical 3D scanner and METROTOM 1500 G2 CT scanner). The resulting scanned models were then compared not only in terms of dimensional accuracy, but also in terms of quality and detail of the obtained data or the time required to prepare the measurement and its implementation.

The paper describes a procedure for calculating the lifetime in the frequency domain, which is supplemented by an experiment. The aim of the experiment was to find the required mechanical properties of the material to describe the behavior of the material during fatigue analysis. Experimental modal analysis was performed to estimate damping, which supported numerical calculation and refined results of numerical simulations. The authors made an estimate of fatigue curve (SN-curves) according to ČSN 42 0363 and ČSN ISO 12 107 standards. Knowledge of material fatigue, statistics, modal analysis and signal processing were used in the experimental and numerical part.

Small holes can be manufactured by several ways. It is important to define in what dimensions the small holes vary. Anyway, drilling is one of the oldest technologies of holes manufacturing. In small dimensions we use the term microdrilling for description. Beside this conventional way of manufacture there are also unconventional methods. Microdrilling bits very often break before they are worn. Therefore, the tool life of these bits its quite unexpectable. It is due to relatively high load against the drill bit strength. So, it is important to choose proper drill bit material, cutting geometry, construction, process liquid, clamping and cutting conditions. These parameters are import for achieving ideal conditions for microdrilling. Even a tiny change in pre-seted parameters can lead to destruction of these delicate tools. Fiber arrays are designed and manufactured for precise positioning of optical fibers in row (1D) or in plate (2D). Fiber arrays can contain most of fibers including polarization maintaining fibers (PMF).

This work deals with the effect of the cutting conditions and the spindle tilt on the surface roughness when grinding complex shaped surfaces of Maraging steel MS1 on an ANCA MX7 5-axis tool grinding machine. It is necessary to grind complex shaped surfaces where high surface quality is important and requested. For this experiment was selected a component with a complex shaped surface which was printed on the 3D printer machine from maraging steel MS1. Since grinding of complex surfaces is being investigated, it is necessary to use CAM software for creat-ing an NC program. The aim of this work is to study the effects of the cutting conditions on the grinding of a com-plex shaped surface in relation to the resulting surface roughness. To do this, it was necessary to design an experi-ment with the appropriate grinding technology, create a clamp, and create NC data in NX CAM software for grinding the complex shape surfaces on the part.