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The article presents the results of the use Six Sigma DMAIC cycle to improve workplace safety and decrease the cost associated with work accidents in the company from the automotive branch. Selected tools of the DMAIC cycle were used at each stage: the project card and the Pareto-Lorenz diagram at the define (D) stage, the matrix diagram at the measure (M) stage, the Ishikawa diagram with the verification of causes at the analysis (A) stage, the 5WHY method at the improve (I) stage and the c control chart at the control (C) stage. Each of the successive stages was based on the results of the previous one in order to achieve a lasting solution for the analysed problem by the implementation of remedial measures. Because of the implementation of remedial measures, the level of work safety in the examined company was improved. The DMAIC analysis made it possible to identify the main causes (Xn) of accidents at work and to objectively evaluate them in order to discover the root cause (Xn!) of the problem. The root cause turned out to be inadequate protection of the lathe due to the protective cover installed too far away from the lathe chuck, which resulted in the catching of protective sleeves or gloves of the lathe operators and accident events in the form of upper limb damage. The solution to this problem was to reduce the gap between the guard and the lathe chuck by adjusting the guard so that no more items of workers' clothing were caught while the machine was running. The article proves the effectiveness of using the Six Sigma DMAIC cycle in analyzing and improving the state of occupational safety and is an incentive to use this cycle and a specific set of tools to analyze similar problems.

Lighting and noise belong to important environmental factors that have an influence on human psyche, concentration, labour protection, sleep quality and so on. This paper is focused on study of light transmission and noise attenuation properties of light active glass materials, which are applied as window and door panels in residential buildings. The light transmission through tested materials was evaluated by means of the transmission coefficient from the illuminance ratio method. The material ability to dampen noise was determined based on the sound pressure level attenuation during sound propagation through the light active glass materials. Different factors, which have an influence on the propagation of light and noise through the investigated glass materials, were evaluated in this work. Finally, the effect of the light transmission through the tested light active glass materials on the daylight quality in a living room was mathematically simulated using Wdls 5.0 software.

The steel 51CrV4 is widely used for production of springs. Materials research into spring steels aims to meet the requirements of industry, which mainly concern high yield and tensile strengths. Ductility has to be retained as the strength is increased. Also, the resistance against brittle fracture is im-portant, measured as fracture toughness. Enhancement of the mentioned mechanical properties can be accomplished by structural refinement. One possible way to refine the final quenched and tem-pered structure is to refine the soft annealed structure before quenching. The article is devoted to the Accelerated Carbide Spheroidisation and Refinement (ASR) with a comparison to conventional soft annealing (SA) in the 51CrV4 spring steel. Both spheroidization treatment (ASR by induction heating, SA by electric furnace) led in different carbide particle sizes. The carbide refinement alters the mate-rial’s behaviour during quenching. Finer carbides dissolve more rapidly during austenitization at the quenching temperature. It is possible to lower the quenching temperature thanks to carbide refine-ment. Mechanical properties after hardening with different quenching temperatures were positively affected too.

Article deals with comparison of cutting forces and surface roughness between materials produced by powder metallurgy M390 and M398 Microclean® from producer, company Böhler. Main interest is the analysis & comparison of the cutting forces and surface roughness after the processing by cutting in-serts with DNMG and WNMG geometry, radius 0.4 and 0.8 mm, after hard turning at the same pro-cess parameters for both materials and all types of cutting inserts. The comparative studies were car-ried out for cutting forces and surface roughness with the aiming to observe the difference between “old generation” M390 and “new generation” M398 PM Steel for future processing in production. The corelation between the cutting forces and surface roughness was investigated with resulting the M398 is necessary to process by higher cutting forces which are linked with higher surface roughness than at M390. It is in relation with higher contain of additive elements and carbides formed by them, even that the material is in delivered condition – soft annealed [1], [2]. These results helped to fulfil the knowledge about both materials in the row of experiments which are provided to increase material properties against abrasion and wear.

The AGVs or mobile robots are well used in today’s manufacturing supply technologies and also can be used in engineering’s education. The motion controlling and simulation of such vehicles are a cru-cial question. This paper introduces the steps of motion planning for a driverless carrier vehicle from the positions initially available to the speed of the wheels. The vehicle is located in the High-Tech Logistics Systems Laboratory of the Logistics Institute of the University of Miskolc. For motion con-trolling and simulation between two points the further modules are necessary: 1. path planner, 2. tra-jectory planner, 3. velocity-voltage converter using velocities gained from trajectory planner, 4. mo-tion controlling and simulation of a motor dynamical model using voltages from the converter, 5. simulation of the path and 6. data processing. In this paper the first two modules are detailed, i.e. the path planning and then the trajectory planning. Path planning is based on a new approach, using Bezier-curves and Hermite curves. The trajectory planning tends to the mininum energy, which can be carried out by the examining the current consumption created in the other modules. The smaller consumption originated from the two curves determines the final path and trajectory.

The milling process is widely used industrially and the quality of the obtained milled products should be controlled because it affects their performance in exercise. This work correlates the quality of the machined surfaces with the adopted locating system, the shape deviations of the workpiece datum and the machine tool. An analytical model was set up and implemented through Matlab® to simulate the quality effects of a milling process. It was applied to two face milling processes characterized by two different locator configurations. It was proved that machine tool volumetric error influences the flatness of the milled surface, while the locator configuration and the datum form deviation affect the orientation of the milled surface, as should be actually.

The article deals with the analysis of the structure and fracture surface of aluminum alloy samples. Alu-minum alloy AlMg9 was used as an experimental material. The material from which the samples were made was supplied as cast without heat treatment, and specifically the material was produced by the continuous casting method. The structure of the test material was examined using a Neophot 32 optical microscope, and the fracture surface of the test sample was examined using a scanning electron microscope (SEM). The fatigue life of the aluminum alloy was tested by three-point bending cyclic loading using the parameters - frequency f = 100 Hz, temperature T = 22 ± 5 ℃ and stress ratio R = 0.11. The analysis showed that cast aluminum alloys are very sensitive to casting defects, such as porosity or the content and distribution of intermetallic phases. If large pores or phases are present on or near the surface of the sample, this can be the dominant cause of fatigue crack initiation and reduction of the fatigue lifetime.

Additive manufacturing commonly also called 3D printing is a process which creates 3D structures according to digital 3D models by successive deposition of material layer by layer. Electrochemical 3D printing is a relatively new form of additive manufacturing, which creates metallic structures by electrochemical reduction of metallic ions from the electrolyte onto a conductive substrate. Advantages of this technology are ability to produce structures of several materials, without inert atmosphere, thermal stresses and without using laser optics. Theoretical part was focused on introduction to additive manufacturing and overview on its technologies, description of principle of electrochemical deposition, overview on electrochemical additive manufacturing technologies and influence of parameters, which affect it. Experiments were focused on effect of selected parameters of electrochemical 3D printing on print rate, mechanical properties, porosity, and microstructure of built structures of copper.

In this paper, the design of a robot is proposed to replace manual labor in completing tasks on vertical planes. The aim is to enhance automation in the workplace and eliminate direct human involvement to ensure personal safety. Firstly, the robot's structure is designed as a five-joint biped with vacuum adsorption capabilities. The forward and inverse kinematics of the robot are analyzed. Secondly, using simulation by ADAMS, five key performance metrics are quantitatively analyzed for both this robot and a Hexapod robot. These metrics include adsorption reliability, external load-bearing capacity, friction coefficient adaptability, obstacle-crossing capacity, and joint torque. Thirdly, the main control chip used for this robot is STM32F407. The circuit system design and physical implementation of the robot are based on this chip. Finally, experiments are conducted to study the actual performance of the robot in vertical cleaning tasks.

In the whole world, the economic loss caused by hull corrosion is enormous. Ship painting has become an important part of ship manufacturing process because it can effectively alleviate the corrosion of ship. The manual painting has disadvantages both in the quality and the efficiency. However, the research of automatic sprayers for a ship hull is not widely used because of the complex environment in the shipyard dock and the huge differences in both size and shape of ships to be repaired. Therefore, this paper pro-posed a new method: according to the ship size and blocks distribution in the blocks’ layout of ship yards, the grid method was used to generate the map model; to solve the problems of high rerouting rate, low coverage and large consumption of calculation in the global path planning, a regional division method was proposed to divide the whole area; to shorten the dock occupancy time, a path planning algorithm based on multi robots heuristic cooperation was proposed. Simulation results and experi-mental data show that the full coverage path planning algorithm proposed in this paper has satisfactory adaptability.

Nickel-based superalloy is a kind of metal material that is widely used to manufacture high-temperature parts in the fields of aviation and aerospace, but it is also a typical difficult-to-machining material. The precision cutting of nickel-based superalloy has always been an important manufacturing problem. Based on the tests of conventional drilling with three kinds of twist drills, the machinability of Inconel 718 was evaluated comprehensively by drilling force, tool wear and machining quality, and the cutting tools suitable for drilling nickel-based superalloy were chosen. Then the experiments of peck-drilling for Inconel 718 were carried out, and the process effect under different peck depth Q was deeply researched. The results showed that the HSS-Co (high speed steel with cobalt) twist drill can meet the needs of low-speed drilling of nickel-based superalloy, while the coated carbide twist drill has better service performance. The drill tip structure of dual clearance angle is beneficial to decrease the cutting friction and improve the machining accuracy. Compared with conventional drilling, the peck-drilling can reduce the cutting force and improve the dimensional accuracy and surface quality. However, it is very important to choose a suitable peck depth Q for fully exploiting the advantages of peck-drilling.

Nowadays, a lot of data is generated in production and also in the domain of assembly, from which different patterns can be extracted using machine learning methods with the support of data mining. With the help of the revealed patterns, the assembly operations and processes can be further opti-mized, thus the profit achieved can be increased. This article attempts to explore the patterns related to the most used Key Performance Indicator (KPI) in manufacturing, the Overall Equipment Effec-tiveness (OEE) metric. The patterns and relationships discovered will be sorted into Assembly Pattern Catalogue (APC). Firstly, a literature review demonstrates scientific relevance. Secondly, it examines the circumstances and methods of samples in the Manufacturing Execution System (MES) data source and Enterprise Resource Planning (ERP) systems. In the third section, the detailed pattern catalogue is defined in the area of assembly. The novelty of the article is that beyond the generaliza-tion of patterns, it characterizes the pattern catalogue with mentioning practical industrial examples.

With the development of welding technology and the improvement of automation level, welding robots are playing an increasingly important role in industrial production. However, during the welding process, due to factors such as material characteristics, welding parameters, or improper processes, defects may appear on the surface of the workpiece, which may reduce the quality and service life of the workpiece. In order to solve this problem, this article used frequency domain feature extraction and nearest neighbor classifier in workpiece detection algorithms under machine vision technology to extract and classify surface defect images of workpiece, and studied the detection method of welding robot workpiece surface defects. The research results indicated that, under the same other conditions, the accuracy of machine vision technology was over 90% for all five different defect types, while the accuracy of traditional technology was between 75.5% and 84%. The performance of machine vision technology was far superior to traditional technology, indicating that machine vision technology could improve the accuracy of welding robot workpiece surface defect detection methods.

With regard to the current economic situation, which deals primarily with energy prices, companies are trying to find reserves within individual technologies. The automotive industry is still a very important industry. One of the ways to improve the material properties of a body part is thermomechanical processing. This is how the B-pillar, which serves as a safety structural element of the car, was processed. The presented article aims to investigate the influence of selected thermomechanical processing parameters on the resulting properties of a B-pillar made of high-strength steel 22MnB5. At the same time, energy saving in the given production process should be used in such a way that it is not at the expense of the quality of the component. Three kinds of experimental production processes with different parameters of thermomechanical processing of steel were proposed for scientific investigation. Based on these proposed processes, several pieces of B-pillars were produced and subjected to further investigation. Changes in material properties were monitored using hardness measurements and subsequently the resulting microstructure of the material was examined for each experimental post.

The paper deals with welding of aluminum alloys using Friction Stir Welding technology. This repre-sents one of the solid-state welding technologies in which the base materials are not melted. This pro-vides new possibilities for the use of special and hybrid manufacturing technologies. The article presents the current progress in the Friction Stir Welding technology, a microstructure analysis of a weld joint created by the FSW method and a heat-deformation computer simulation of an aluminium alloy speci-men in the program Ansys.

Machining is an important part of the manufacturing process in the engineering field. Turning is one of these areas. At present, almost exclusively exchangeable cutting inserts are used in production machining. The article describes the research in the field of their wear, where the electron microscopy was used to evaluate the results. Electron microscopy is a very important aid in research in many are-as not only of human activity and also is the important aid in the field of mechanical engineering and manufacturing technologies. The results thus obtained can make in a given area it clearer and better document the resulting situation. Within the experiments, selected cutting inserts were used and the given material was machined. The electron microscope Tescan Vega 3, which is available at the workplace where the experiment was conducted, was used to evaluate the resulting wear. In the frame of experiments was also performed the composition analyze of used cutting inserts. Analyzes of the machined material were also performed to confirm the declarations from the supplier.

The study of the cooling process of a gun barrel is of great importance in the field of ballistics and weaponry. This is because the cooling process directly impacts the gun's accuracy, precision, and longevity. To minimize these effects, the geometry of the barrel is optimized, among other things. The article examines the cooling process of the copper plate and barrel with a structured surface. The study aims to determine the structured surface's effects on heat transfer through radiation and convective components. The work focuses on conducting experiments and numerical simulations to observe and evaluate the cooling process of the studied objects in the environment. The results of experiments and numerical simulations were compared to find out the possibility of substitution of experimental measurement by numerical simulation even I n so difficult flow conditions.

The paper presents the results of measurement uncertainty obtained with a tool probe for 4 cutting tools with different values of the nominal radius rf = {3,4,5,7} mm. The tool probe was used to collect experimental data enabling the evaluation of the uncertainty budget of the measuring system. The evaluation was made based on a statistical analysis of measured tool radius values. Each radius value was determined by 30 repetitions of tool probe measurement. The mean value and the standard uncertainty of obtained results were determined. Assuming that the expansion factor was k=2, the expanded uncertainty U was determined, its value ranging between 0.00142 mm and 0.00462 mm for the tested tool radius values. The standard uncertainty ranged from 0.00081 to 0.00231 mm. According to the manufacturer's specifications, the standard uncertainty of the probe is 0.0015 mm.

The paper is focused on the dynamic response of a Hybrid III crash-test dummy during low-severity frontal (forehead) and side (temple) head impacts. The measurements used a pedestrian dummy (Hybrid III 50th percentile male dummy, Jasti Co., ltd., Tokyo, Japan) and a unique pendulum impact testing machine (impactor) of own design and construction. The tests were conducted at two various impact intensities (velocities) that did not exceed the speed of 1.6 m.s^-1. The primary outcome variable was a resultant magnitude of acceleration measured on the vertex of the dummy’s head and the results were compared to 11 human volunteers. The goal of the study was to analyze the biofidelity of the Hybrid III Dummy in a pedestrian setting during low-severity frontal and side head impacts by comparing the dynamics and kinematics of the dummy’s head to human volunteers.

The paper deals with the technology of production of deep-drawn plates from alpha brass CuZn30. Surface and hidden defects are often observed in these deep-drawn sheets. The research was aimed at reducing the occurrence of these defects and subsequently reducing scrap and increasing the quality of these metallurgical products with a tighter tolerance of the required structural and mechanical properties throughout the length and width of the sheets. The production technology was monitored from the preparation of the batch and casting parameters on the existing operating equipment, through the processing of the ingots by hot and cold rolling, to the recrystallization annealing of the sheets in coils in a hatch furnace and the subsequent continuous pickling and passivation of the final strips. Properties were monitored after each technological operation of production. Specifically, macrostructure, microstructure, microporosity, tensile mechanical properties, and hardness were analysed. The results showed that the chosen production technology has sufficient homogeneity of properties.

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.

This study focuses on performing the analysis of manipulator operations on the machining line of precision mechanical products using the Human-Machine correlation analysis tool through images collected from the camera, wasteful operations incurred in machining according to Lean Six Sigma (LSS) standards to control fluctuations in the machining line, improving the overall productivity of the line (OEE). Specifically, contributing to improving productivity, quality, and competitiveness of the company in the market, create a good product image for consumers. This paper proposes a 7-step quality control (QC) cycle improvement model, called 10 step QC cycle. In step 5, use Man - Machine correlation analysis tool from video images to identify wasteful activities. In step 6, we propose a Direct Numerical Control (DNC) model to call the machining program for MC machines using a barcode system and a computer vision model for human identification at each processing line according to a controlled fixed layout. The right people have been trained enough to operate the line; the specific result is eliminating the occurrence of accidents in processing from 7 cases to none. A model of a product dimensioning system implemented for fully automated product quality control combined with redesigned machining jig with a vapor sensor system eliminating the reliance on human manipulation Specifically, the result from this improvement activity is the increase in productivity from 115 products per 8 hours to 155 products per 8 hours and the handling time has decreased from 1.3 hours per day to 0.36 hours per day (reduce 0.94 hours per day). The Partial Least Squares Structural Equation Modeling (PLS-SEM) is used to analyze the results of the survey of employees' opinions about the usefulness, convenience, and technical factors after the operation. The results from improvement activities show that user loyalty is highly appreciated in terms of usefulness and convenience. However, in terms of technical factors, it is still necessary to improve the quality of the information network system, the barcode scanning system and the quality of barcodes in the oil environment

Titanium alloys are among the biocompatible materials that are used for biomedical implants. From the point of view of the reactivity of the human body, it is important to know the state of the surface of these materials, which in technical practice is represented by the term surface integrity, which includes a complex of evaluated properties. One of the classic approaches is the evaluation of the surface roughness and the properties of the stable oxide layer, which influence the formation of the connection of the implant with human tissues and influence its acceptance. Another frequent approach is the use of optical metallography, especially for the assessment of material thickness, distribution and character of corrosion attack. Less common is the use of electron microscopy in the evaluation of the surface, which in this case is affected by the action of corrosion. Samples of both pure titanium and Ti6Al4V alloy were divided into sets according to surface roughness and subsequently exposed to corrosion for different periods of time. The presented article is devoted to basic analyzes of the effect of roughness on corrosion behavior using not only classical optical but also electron microscopy.

The aim of this work is to propose a methodology for evaluating inhomogeneity due to the sedimenta-tion of fibres in High-Performnce Concrete (HPC) mixtures. HPC mixtures makes better mechanical-physical properties than ordinary concrete. To achieve higher strengths, the fine-grained matrix is rein-forced with the reinforcement – fibres. The type of used fibres and their homogenization in mixture has an influence on the final mechanical properties of HPC mixture. Four concrete mixtures with same com-ponent proportion was chosen for experiments. Water was the only one component, that was changing in mixture recipes. Steel fibres with a ratio of the diameter to length = 0.3/20 were used as reinforcement. The fibre volume in mixture was 1.5 %. The microscopy analysis was used for evaluation of the fibre dis-tribution in the test specimens. It was obtained, that the concentration of the fibres increases with dis-tance from the surface to the bottom of the HPC structure and this non-homogeneity increases with higher water dosage. The dependence of sedimentation of fibres on composition of HPC mixtures can be used for evaluation and optimization of final mechanical properties of the HPC structures.

An efficient polishing process has been carried out at the polishing speed about 200 mm/s in vacuum with temperature of 850˚C. With the polishing time reaches 120min, the surface roughness of polished could get to Ra0.016 compared to original Ra9.67. Mass loss rate per hour was used to quantify the polishing efficiency. Increasing the polishing pressure could get high mass loss rate, which could be used in the rough machining process. In fine machining process, the polishing pressure should be lower and the high polishing speed should be remained. The 3D morphology from atomic force microscope(AFM) shows there are some summits about 30-40nm in height, and the summits take into the shape of directional narrow cone.

A model-based viewpoint planning and filtering method is proposed to determine the position and pose of viewpoints in 3D reconstruction of multi-view images. The method first determines the necessary parameters to control the camera position and attitude. Second, the mathematical error model is developed and combined with stereo overlap to guide viewpoint selection. According to the shooting distance, a dense candidate view area is then established, the subview collection is screened, & a view supplement scheme is proposed for the area where the candidate view cannot be shot, improving the integrity of the resulting data. Experimental results demonstrate that our viewpoint planning method has high shooting coverage & highly accurate 3D reconstruction.

In the automotive industry, deep-drawn sheet metals are widely used and protective coatings are ap-plied to its surfaces to improve certain performance properties (e.g. to increase corrosion resistance). Sheets with these coatings are stressed during the forming process of the part and cracking of the protective coating may occur. The main goal of this paper is to determine the resistance of a Zn-Al-Mg based protective coating to uniaxial and triaxial stresses, and also to determine how effective anticorrosion resistance the coating provides to the base steel matrix in the event that cracking occurs. It has been shown that both uniaxial and triaxial loading leads to a failure of the Zn-Al-Mg coating integrity. Salt spray corrosion tests of 3 and 6 weeks were subsequently performed on both deformed and undeformed base material samples. These tests showed that a continuous Al2O3 layer is formed between the steel matrix and the coating, which, irrespective of the formation of cracks in the coating, is the main contributor to the increase in corrosion resistance of the sheet.

Car manufacturers are constantly looking for new options to make the vehicle more attractive to the cus-tomer. In terms of design, this is usually done in the middle of a model's life cycle, when a so-called facelift of a production model is carried out. This involves small changes to the shape of the bodywork to improve the design of the vehicle until it is time for a new model range. This paper discusses a case study that focuses on the modification of the rear body components of a ŠKODA Superb III in Combi version. The aim of the study is to assess how the proposed modifications will affect the aerodynamics of the vehicle. The most sig-nificant changes concern the rear spoiler and finlets. The aerodynamic properties are assessed based on CFD simulations that are performed for a series production and a modified variant of the vehicle, and the results of which are compared and discussed.

This paper discusses the modeling and simulation results of a new multi-material for a cost-effective Selective Laser Sintering (SLS)-based 3D printer. As this technology utilizes several materials, the me-chanical property analysis of multi-materials is crucial for manufacturing an object with the desired physical characteristics. Firstly, the development of a database of the SLS 3D printing materials is ac-complished and based on the mechanical properties of materials, this optimization technique is proposed. Secondly, enhancement of physical property by stiffeners is considered and based on the stiffening tech-nology, and an alternative optimization method proposed. Finally, two different material minimization methods are discussed in this research. The first method is based on the embedded materials with desired mechanical properties for enhancing the mechanical properties of the printed objects, which are twice optimized by this method with increased material saving. The second method is designed to use stiffeners to improve the stiffness characteristics of the materials, and then, perform material optimization. This method is effective with more suitability to complex composite geometries. Thus, the methods help to reduce materials used as well as the production cost in 3D printing technology.

The purpose of this contribution is to investigate different mechanical properties of various types of rubber composite materials that were filled with carbon black nanofiller. The rubber composites were produced from three different basic rubbers. Moreover, the composites were produced with different volume concentrations of the basic rubbers including their various ratios. Mechanical properties of the tested rubber composites were investigated by means of tensile testing, Shore hardness, rebound resilience, mechanical friction, abrasion, visco-elastic behaviour and vibration damping measurements. It was found in this study that the rubber composition has a significant influence on the stiffness of the investigated rubber composites, and thus, on their mechanical properties.