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The aim of this article is to approach the measurement of forces and pressures of collaborative robots. In the article, research will be carried out on measuring the forces and pressures of a collaborative robot before putting it into real application. Force and pressure values will be measured using appropriate measuring devices. The measured results will be compared with the ISO/TS 15066:2016 technical specifi-cation and subsequently evaluated.

The continuous development of thin coatings for different applications and using various coating meth-ods require the characterization of these newly formed surfaces to evaluate their utility properties. Binary thin coatings of titanium (TiN) and zirconium (ZrN) nitrides were prepared using the Arc-PVD (Ca-thodic Arc Deposition) method. Differences were observed in the structure and morphology of the thin coatings and the change in tribological properties at room and elevated temperatures (150 °C and 300 °C). The research is focused on evaluating the frictional properties of the coating using the Ball-on-Disc method in the dry friction mode. The emphasis is placed on the resistance of the thin coating to wear. The nanohardness was measured to be 26.2 GPa for TiN and 24.8 GPa for ZrN. Index of resistivity against plastic deformation H³/E² (plastic deformation resistance) for ZrN coating – 0.087 and TiN coating – 0.095, H/E (plasticity index) for ZrN – 0.059 and TiN – 0.060. Better friction properties and wear resistance (at 150 °C) were found for the TiN coating compared to the ZrN coating.

In order to quickly measure the straightness parameters of the deep hole/blind hole axis, a robot for measuring the straightness of the deep hole/blind hole axis based on the photoelectric prin-ciple is designed. Using the linearity of the laser as a reference, the straightness of the inner hole can be detected through the function that the PSD sensor can accurately locate the position of the energy center of the light. By studying the relationship between the position of the light spot and the output voltage of the PSD device, the measurement model of the straightness of the deep hole axis is derived. During the measurement, the robot spiral driving mechanism moves back and forth inside the deep/blind hole, and the automatic centering mechanism realizes the precise positioning of the deep/blind hole axis. The laser fixed on the axis of the automatic centering mechanism can illuminate the PSD target to obtain the current position data of the deep/blind hole axis. Use the least square median method to eliminate the gross error of the obtained data, and the least square principle fitting can obtain the measurement results of the current axis straightness. In order to ensure the measurement accuracy, the measuring robot is calibrated by a standard ring gauge and used for the age of the pipe with an inner diameter of 135mm to obtain an error accuracy of less than 0.05 mm for the axis.

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.

This paper proposes a solution not previously used in the forging industry, which aims to reduce the proportion of arduous human labour. The concept of a prototype robotic station for hot forging includes a system that allows the selection of batch material with its heating, the execution of the process of lu-brication of forging tools and the forging itself, synchronised with the feeding and removal of material using full automation, in accordance with the idea of Industry 4.0. At the same time, by increasing the repeatability of the entire forging process and changing some of its key parameters, it will be possible to influence the durability of the tools used during its implementation. In order to verify the impact of such a modified technological process on forging tool life, computer simulations of forging were performed, where the currently applied technology using hand forging was compared with a conceptual automated process.

Today's milling cutting tools are produced in various types and shapes for a wide variety of machining processes. Development continues and offers new technological solutions. The design of replaceable milling heads offers a significant cost reduction, as only the worn-out part is replaced instead of the en-tire tool. The tough connection between the tool and the shank achieves stable performance in roughing and finishing milling. Because of the possibility of using different milling inserts, the number of neces-sary tools will also be reduced and the flexibility of using milling tools will increase. The article exam-ines the cutting forces when machining a milling head produced by additive technology and made of Onyx material, which is reinforced with carbon fibre.

To be competitive, present-day manufacturing industries strive to optimize manufacturing parameters and produce quality products consistently. From various manufacturing processes, welding is one of the key processes for joining a large variety of indispensable products including the production of automotive body in white structures, assembly of large metal civil structures, nuclear installations, pressure vessels, aircraft, and spacecraft materials, etc. In order to get the level of quality requirement of welded components, an optimized combination of welding parameters plays a vital role. However, the realizations of this optimum combination of welding parameters for all processes in different conditions are the big challenge for the manufacturing industry. The current study presents a critical assessment of the various researches in the fields of gas metal arc welding of steel to create a descriptive picture of the effect of input parameters on weld quality characteristics. To realize this, intensive literature reviews and comparisons of different results have been made, and findings have been incorporated. Where there are differences in trends of parameter effects, proper explanations and justifications have been drawn. As a result, it was found that arc voltage, welding current, wire feed rate, and travel speed affect the quality of the weld (mainly penetration, bead height, bead width, and heat affected zone) significantly compared with other parameters considered in the context of this paper. This shows that the proper setting of the optimum combination of welding parameters specifically, arc voltage, welding current, wire feed rate, and travel speed yield the desired quality level of the weldment.

This study aimed to investigate the influence of single-wall carbon nanotube (SWCNT) content on the mechanical properties of polyurethane (PU) nanocomposites. The SWCNT content varied from 0 wt% (reference sample) to 2 wt%. Tensile, hardness and Charpy impact tests as well as dynamic me-chanical analysis (DMA) were performed. Based on the test results it was observed that an increase in the content of single-wall carbon nanotubes resulted in significant improvements in material strength and stiffness. Furthermore, atomic force microscopy (AFM) was used to examine microsurface to-pography of the samples and to obtain spectroscopic curves, based on which local elasticity was eval-uated. Overall, performed measurements indicate that the incorporation of SWCNTs into PU matrix makes resultant nanocomposite stiffer and more resistant to deformation. The results highlight the potential of SWCNTs as effective reinforcement of polyurethane-based nanocomposites.

Nowadays, the digitalization of the production process is an indispensable part of the stampings production in the pre-series stage, but also as a subsequent support for series production. Automotive producers are under pressure to comply with the ever decreasing CO2 production standards for cars, which predicates the use of modern material types with an advantageous weight-to-strength ratio. This paper focuses on the use of mathematical modelling in a numerical simulation environment to predict the deformation process and subsequent material spring-back of dual-phase steel DP500. The material data and characteristics are used to define the material computational model in numerical simulation. The results of the numerical simulations are then compared with the stamping obtained by a real pressing process, where their shape comparison and further evaluation of the used material models and selected parameters are performed.

The presented article focuses on the surface analysis of the components manufactured by different additive technologies and their reverse digitization. Sintered components were manufactured by SLM and ADAM technologies, while their surface was analyzed using a progressive optical measurement method. To examine the possibility of reverse engineering, the components were optically scanned with a laser scanner and compared to their CAD model. Based on empirical experience, to scan opti-cally the metal and lustrous surfaces is a challenge. The components were manufactured from anti-corrosion materials 17-4 PH and 316L–0407.

FeCoCrNiZr high-entropy alloy was melted by vacuum arc melting. The alloys were vacuum annealed at 873, 1073, and 1273K, respectively. The microstructure, compressive mechanical properties, thermal stability, and hardness of as-cast and annealed FeCoCrNiZr alloys at different annealing temperatures were investigated by using X-ray diffractometry (XRD), scanning electron microscopy (SEM), microhardness tester and universal material testing machine. The results reveal that it has no noticeable change in the phase composition of the alloy after high temperature annealing. The as-cast FeCoCrNiZr alloy is composed of the body-centred cubic phase and Laves phase. In the 1073K annealed state, the σ phase was detected in the alloy, and the alloy's hardness reached a maximum value of 915.94 HV0.2. The hardness of the alloy in the annealed state is obviously higher than that of the as-cast alloy, and the increased compressive strength is the result of the combined effect of the hardening of the C15 Laves phase and the solid solution strengthening of the Zr atoms.

The paper presents the possibilities of using the wavelet transform to filter the cutting force signal. Tests were carried out by dry turning on the Ti6Al4V alloy with variable cutting parameters. Four blades with different nose geometry and coatings were used. From the recorded waveforms, the mean values of the force component Fc and the load stability coefficient were calculated. The measured force waveforms were filtered with Daubechies 4 (db4) and Daubechies 6 (db6) wavelets. From the ratio of the load stabil-ity after filtration to the load stability before filtration, the noise and disturbance values generated during the turning of the tested alloy and the force measurement were estimated. The conducted research shows how the machining conditions affect the values of force, stability, and thus also the variability of the cutting edge load when turning a titanium alloy. They also show the effectiveness of the Discrete Wave-let Transform (DWT) in separating the noise from the force signal.

Casting with a disposable pattern is a method employed to produce intricate-shaped castings. This manufacturing technique falls into the near-net shape methods category, which ensures that the result-ing castings closely resemble the final components. Its primary application lies in industries where pre-cision and complex castings are of paramount importance. Typically, castings manufactured using this method utilize higher-cost materials. The focus of this study centres on the utilization of reverse engi-neering in the production, modification, and inspection of wax injection moulds during the casting pro-cess. Within the scope of this investigation, a non-contact method employing the Kreon arm with the Aqulion scanner was implemented. This method facilitated the generation of a digital scan, serving as the foundation for designing and validating the mould for subsequent practical application.

In terms of surface protection of outer car body parts, zinc coatings are currently highly used in automotive industry. Concretely, hot dip galvanized (HDG) sheets are used in most cases. However, other possible alternatives such as zinc-magnesium coatings (Zn-Mg), which are usually referred to as ZM coatings, are also more frequently applied. Thanks to magnesium, the corrosion resistance is significantly increased, which also positively influences the coating thickness. On the other hand, the presence of magnesium makes this coating harder and brittle, which significantly limits its use to produce complex car-body stampings. To prevent the stamped material being drawn into certain parts of the drawing die, special types of draw-beads (so-called edge beads) are used. The effect of draw-beads geometry on the level of damage of ZM coating using experimental tests is evaluated in this article. For comparison, the same experiments were also done for HDG zinc coated specimens. Then the comparison of both methods using TESCAN MIRA3 scanning electron microscope was used and the level of damage of both tested coatings was assessed.

Aiming at obtaining ultra-low kinematic stiffness and improving the isolation property of low frequency vibration, it is necessary to solve the coupling parameters and rated load of air negative pressure characteristics and rubber characteristics, in order to achieve an ideal elastic characteristic curve of air negative pressure spring. Firstly, the background and working principle of the negative pressure rubber isolation were introduced. In addition, the FEA model of isolator is built based on Mooney-Rivlin constitutive model of rubber. Furthermore, to testify the validity of the mathematical model, the static characteristic and simulation analysis of isolator are studied. The experimental data and characteristic curve of different negative pressure were obtained, the simulated results show a good agreement with those of corresponding experiments. Finally, they also illustrate the validity of the vibration isolation, which realizes better performance of low-frequency vibration isolation.

This study focuses on the analysis and solution of thread production in thin-walled profiles. It explores three different threading technologies, including cutting, forming, and extrusion. The issue of a screw joint in a thin-walled component is complex due to the stiffness of the joint and the short length of the thread. Hence, the careful choice of a suitable manufacturing process for producing inner threads in thin-walled components holds significant importance. The study entails monitoring the hardening of surface layers of materials after thread production, in conjunction with the acquisition of microstructure images of the experimental material. The outcome is a comparative evaluation of different individual thread production technologies.

Joining technologies are very important aspects of production process in the automotive. Especially regarding the use of newly developed types of materials (e.g. ultra high-strength steels or aluminium alloys), in addition to welding technology, e.g. riveting or adhesive bonding technologies are used. Submitted article evaluates the effect of the riveting force on the final quality of riveted joint when joining aluminium alloy EN AW-6016 (thickness 2 mm). The actual evaluation of the riveted joint was carried out using a shear test, measuring the hardness HV01 and deformation analysis of specimen using non-contact optical scanning (ATOS III Triple Scan system).

Traditional assembly sequence solving methods often face problems such as combinatorial explosion and low efficiency in solving complex products with multiple parts. To improve the level of assembly sequence planning (ASP), an interference matrix is established to express the basic assembly information of a product. Taking the stability of the assembly sequence, the number of assembly direction changes, and the number of assembly tool changes as evaluation indicators, a fitness function is constructed. An improved particle swarm optimization (IPSO) approach for ASP is developed based on the peculiarities of the ASP issue. Redefining particle positions, velocities, and their update operations, and introducing mutation operators in genetic algorithm (GA) to improve the ability of PSO algorithms to jump out of local optima. Furthermore, the algorithm's convergence speed is enhanced by adjusting the value of the inertia weight. Finally, an example is provided to demonstrate the IPSO algorithm's usefulness and efficiency.

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.

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.

The growing use of composite materials in various industries implies the necessity of conducting research on both their manufacture and subsequent machining. One of the main problems in composite machining is the selection of a suitable cutting tool. This study investigates the effect of the geometry and material of a milling cutter on the quality of a milled composite part. A carbon fiber-reinforced epoxy resin matrix composite was tested. Two cutting tools were used: an end mill with PCD inserts with a diameter of 12 mm and the number of teeth of 3 as well as a PCD-coated carbide end mill with a diameter of 12 mm and the number of teeth of 4. Variable technological parameters were used. The quality of the machined surfaces was assessed based on burr height and selected profile roughness parameters. Results showed that for the milling process conducted with the same technological parameters, the surface quality obtained with the 4-tooth PCD-coated carbide tool was higher than that obtained with the 3-tooth tool with PCD inserts.

Reusing the powder across consecutive route cycles is typical in a Selective Laser Melting (SLM) process since it is more sustainable and cost-effective. The theoretical part of the paper is oriented on the explanation of the SLM method principle, construction, and parameters of the device Renishaw AM250 used for manufacturing samples made of AlSi10Mg aluminium alloy. The experimental part focuses on evaluating powders that had been used in the process for a long time with periodic ‘rejuvenation’. The main aim will be to monitor whether the samples will be affected and if they achieved the required quality of mechanical properties and compare results with virgin powder and manufacturer sheets for virgin powders. The experimental part further describes the procedures and analysis of the microstructure of the samples. AlSi10Mg aluminium alloy was chosen because of an assumption that it will be sensitive to increased oxygen content. A strong affinity for oxygen uptake exists in AlSi10Mg. Therefore, preventing the contamination, careful handling is required.

The paper describes the effect of laser traverse speed during laser hardening on hardness and micro-structure. The experimental material is hot work tool steel AISI H11 with samples sized 100×100×35 mm. The initial state of the material before laser hardening is quenched and tempered. The laser hardening temperature is constant at 1100 °C, selected laser traverse speed was 1, 2, 4, and 6 mm/s. A numerical simulation performed in DEFORM-3D software before the experiment showed tendencies of temperature displacement and expected course of hardness. Increasing traverse speed leads to de-creased laser-hardened depth and decreased hardness drop in the heat-affected zone (HAZ). The ex-perimental program confirmed the results of the numerical model. The differences in the microstruc-ture were investigated by light (LM) and scanning electron microscopes (SEM), which revealed an evident difference between the surface area and the locality with the lowest hardness. Local differ-ences from the perspective of presence of carbides were analysed by energy dispersive spectroscopy (EDS). This investigation was performed to optimize laser traverse speed to improve the subsurface hardness profile, which is essential for the lifetime and reliability of forging dies.

The presented study focuses on the study of polylactide acid (PLA) material, which is a frequently used material in 3D printing. Surface modification using DCSBD plasma discharge is proposed as a way to improve the adhesion between individual layers of material. Adhesion is a critical factor for achieving high-quality print output, as low adhesion can cause individual deposited layers of material to separate and ripple during printing. Dynamic Mechanical Analysis (DMA) is used to determine the glass transition temperature (Tg) of a material. Tg is important because it determines how difficult the material is to print, the closer the Tg is to room temperature, the easier the material is to print. How-ever, after printing a layer of material and subsequently cooling it to room temperature, the material begins to shrink and wave due to the change in material expansion. This can have a negative effect on the adhesion between the layers of the material, which can lead to separation of the layers. The presented study tries to find a way to improve the adhesion of individual layers of material. Surface modification by plasma discharge appears to be a promising method that could improve the adhesion between individual layers of PLA material.

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.

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.

There is a lot of applications for manipulating industrial robots nowadays. Maximizing the tasks that can be assigned to robot manipulators is one of the criteria for deciding if their application is appropri-ate. The article discusses the topology optimization of the gripping jaws of an industrial robot to reduce the jaws' weight. The previously used gripping element made of C50E steel was optimized to reduce the weight of the jaws. Shape optimization was performed based on analysis from CAD programs Inventor Professional 2022, Autodesk Fusion 360, and Ansys Discovery. The new jaws were manufactured by the additive technology of selective laser sintering (SLS) from PA12 material. The optimization resulted in a significant reduction in weight compared to the original jaws. As a result of optimizing the weight of the designed jaws, it was possible to increase the weight of the object of manipulation.

The presented work deals with the research of the super-alloy Inconel 713LC, on which an Al-based coating was applied using the "Out-of-pack" diffusion coating process, or CrAl. In this contribution, the results of measuring the thickness of thin coatings using a confocal laser microscope and the method of impedance spectroscopy are presented and discussed. This can demonstrate the possibility of being used also for researching the properties of thin layers using a VF probe, which, thanks to the use of ferrite, has a practically constant inductance in the entire frequency range, and the presence of a metal sample in the magnetic circuit of the probe was manifested as a result of eddy currents by a significant decrease in the inductance value at higher frequencies. However, the measurements require precise measurement of impedance with an accuracy of 1mΩ and phase angle with an accuracy of 0.001° with high stability of the measuring frequency. For a better assessment of the parameters of the layers, it is necessary to extend the frequency range of the measurement to the range of MHz units.

The presence of reinforcing particles SiCp seriously affects the cutting surface quality of SiCp/Al materials.In this study, different machining parameters were tested to obtain good surface quality, and the surface quality of SiCp/Al alloy material under different milling parameters was studied by using the surface profilometer and scanning electron microscope to explore the effect of cutting pa-rameters on surface quality. The results showed that the Surface roughness value increased with the increase of feed rate and milling speed, and milling speed was the dominant factor in the microstruc-ture evolution of the machined surface. In addition, an exponential model related to feed rate and milling speed was constructed.

Article presents a novel approach to addressing the challenge of forge-free filling of gas cylinder valve knobs in the context of the pneumatic shock absorber utilized within elevator systems. The shock absorber is a critical component responsible for ensuring accurate and efficient transportation of charge material to the electric inductor of automatic hot forging presses. Precise control of the shock absorber's operation is essential for maintaining proper system functionality and minimizing deficiencies. To investigate the system's response to changes in shock absorber operating parameters, the authors conducted a comprehensive simulation. The simulation results revealed that by identifying specific and optimal operational characteristics, the level of deficiencies can be significantly reduced. These findings offer valuable insights into system behavior, facilitating the optimization of shock absorber operation and overall improvement of the hot forging process. Implementation of the optimized shock absorber operation based on the simulation outcomes can enhance productivity, cost-efficiency, and quality in the hot forging industry.