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Cycloid gear drive is widely used in robot cycloid planetary reducer, and the transmission accuracy is the key property of the reducer. The standard cycloid transmission is a multi-tooth mesh. The modification method has attracted extensive attention as one of the important parameters of the cycloid drive. The influence of the isometric and shifting modification of the cycloid gear on the cycloid transmission backlash was analysed according to the characteristics of the multi-tooth mesh and the profile equation of the modified cycloid gear in this study. Combined with the backlash analysis, a multi-objective optimization mathematical model of cycloid gear modification parameters was established to ensure the backlash and strength of the reducer. The study showed that the modification combination mode and parameters were obtained under different application conditions, thus providing a certain reference for the modification parameter design of cycloid transmission.

The design of the formwork support for a certain section of the Beijing subway project was carried out in this paper. And the disk lock formwork support was used in the engineering.It was analyzed on the the design of the formwork support for the roof with the thickness of 1.5m of the interval engineering. The manual calculation and the sap2000 finite element analysis were also used in the paper.The effect of the diagonal brace and its number were analyzed in addition to the design of the formwork support. It was showed that the axial force of the standing tube tends to be uneven with the increase of the number of slant bars in the framework. And the axial force of the standing tube connected to diagonal brace is larger than that of the framework without brace significantly. So it will be dangerous to the framework without considering the effect of it by the manual calculation.

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.

Main aim of this paper is to analyze the thermal behavior of different cooling channels and to describe advantages of manufacturing of a mold with these channels using a 3D printer instead of drilling machines. This work was primarily done by the usage of virtual simulation. Validation of thermal simulations was performed by usage of simple analytical solution. A simple model of molded brick was designed to analyze the cooling time and the temperature distribution in the mold when changing the cross section of the cooling channels. Three types of different rectangular cross-sections and one circular were chosen. All of them have the same area. The cooling channel with circular cross section was positioned closer to the part in next design and influence of this change was analyzed. Last tested configuration is conformal cooling channel with a channel path twice longer. It is obvious, that most suitable configuration of cooling channels is combination of conformal design with rectangular shape as close as possible to plastic part.

In the urban railways environment, there is considerable stress of the track due to operation, which results in extensive deformation of the track geometric position, wear of the rail heads, expansion of the free channel of the track, leading to an increase in steering forces in the rail-wheel contact and further worsening of the situation. The authors perceive this situation primarily as a consequence of an inappropriate bogie concept of the operating vehicles - not of the track quality. The article focuses on designing a new bogie concept that takes into account the specific environmental conditions for which it is intended. The presented bogie design is characterized by the mounting of the frame on the wheelsets by means of three bearing boxes and the presence of a mechanism for adjusting the radial position of the wheelsets during ride in track arcs. This is a new, unconventional solution for which a number of patent applications have been filed. Simulation analyzes of vehicle ride with the designed bogie are currently underway. On the basis of the first results, it is foreseen that the design will increase the life of the track several times, reduce the energy consumption of vehicles and the environmental load of the environment through the transport system.

Today, machine learning regression methods are quietly but fundamentally transforming cost and time estimation in manufacturing: from early pricing to labor planning to operational order management. This survey offers a comprehensive map of approaches - from linear models, to tree ensembles (RF, GBM, XGBoost) and shallow neural networks, to multi-target and tensor regressions that can exploit data structure across BOM items and sequences of operations. With an emphasis on SME conditions, we show how to reconcile three often conflicting requirements of practice: accuracy, explainability, and integration into existing data flows (MES/ERP). The paper presents a comparative taxonomy of methods, recommended validation practices (MAE, RMSE, MAPE, R² including confidence intervals) and a pragmatic adoption trajectory: from regularized multiple regressions to tree models to multi-output formulations sharing re-presentations across operations. Consolidated findings show that modern learners consistently outperform traditional baselines when supported by careful flag engineering, drift management, and data standardization. As a major research-application contribution, we propose a unified multi-objective framework for simultaneous cost and time prediction that combines domain (queueing/simulation) features with data-driven regression to enable transparent decision making in pricing and capacity planning. The study thus creates a bridge between theory and manufacturing practice and invites the reader to systematically but achievably deploy ML in everyday decision making.

Several models of FDM machines, characterized by different architecture and hardware components, have flooded the market in the last 5 years. As a result, given the high sensitivity of FDM to the specific machine characteristics, the search for optimal printing parameters is a renown problem. This two-parts paper proposes an easy-to-follow and low-cost procedure for the characterization of any given FDM machine. The method allows the evaluation of the effects of a wide selection of FDM process parameters on the quality of 3D printed parts. The first part focused on the definition of a series of metrics to be measured on a series of test prints to evaluate the quality of the produced parts. The evaluation of seven quality parameters on a single print is made possible thanks to: i) a specifically designed specimen that is made available to the user and ii) a rigorous and repeatable measurement procedure, which are both discussed in the first part of the paper. This second part presents the characterization procedure, the statistical tools used in the experimentation (DOE tools and principles are adopted throughout the experimentation) and provides guidelines to be used for the characterization of any FDM machine. The whole procedure is tested on a desktop FDM machine to demonstrate obtainable results, proving the efficacy of the proposed methodology and highlight strengths and drawbacks of the approach.

Aiming at a kind of grinding head of high-speed precision roll grinder, its structure characteristics and heat source characteristics are analysed, and the characteristics of heat source is calculated. On these bases, the weakness of grinding thermal characteristics is found through the numerical analysis of thermal performance of roll grinding head, facing the thermal error of sensitive area, optimization method which unites multi objective and single objective are adopted to optimize the thrust oil film bearing of the roll grinding head, after that numerical analysis of thermal performance of roll grinding head is analysed. Analysis results show as follows: temperature of the optimized oil film thrust bearing is improved obviously. The oil film performance between the bearing and the main shaft is stability, and it has had effective prevent the phenomenon of metal dry friction happening. As a result, the grinding accuracy of the grinding roll is effectively improved.

Today, considerable attention is paid to the production of solid castings (approx. 2000 kg) from cast iron with spheroidal graphite. The metallurgical preparation of large quantities of melt is very difficult. This difficulty is related not only to the melting and preparation of large quantities of melt, but above all to its metallurgical treatment - inoculation and modification. Melt modification ensures the production of cast iron with spheroidal graphite. Material castings, such as machine tool components, cannot be destroyed to determine the quality of the cast iron produced. Therefore, this paper outlines a methodology to proceed in determining the quality of manufactured castings. It is possible to observe the chemical composition of cast iron, thermal analysis of cast iron using liquidus temperature value, subcooling temperature, eutectic recalescence, primary solidification recalescence, eutectic solidification time. Furthermore, to observe the mechanical values of cast iron (yield strength, ultimate strength and ductility) on fabricated bars of overmolded Y blocks or to observe the micro-structure of cast iron on microscope.

Investigation of cutting forces in metal cutting is of great importance for defining the effectiveness of the production as well as its impact on product quality. Several researchers studied the effect of cutting parameters on the cutting forces through statistical analysis; however, very few studies use the normalization of the data. Normalization reduces the skewness in the data and increases the accuracy of the results, which can be beneficial in modern industry where AI is being integrated with manufacturing. This research aimed to study the statistical analysis of cutting parameters and cutting forces using log-normalization and compare the accuracy of results with absolute data. The study uses a three-axis piezoelectric dynamometer to measure the cutting forces in the turning of X5CrNi18-10 steel. The results suggested that feed influences the cutting forces during machining. Coolant helps to reduce the cutting forces during the turning of hard steel. Log-normalization increases the accuracy of the results. These results can be used to predict cutting forces during the turning of chromium-nickel alloy steel.

Several models of FDM machines, characterized by different architecture and hardware components, have flooded the market in the last 5 years. As a result, given the high sensitivity of FDM to the specific machine characteristics, the search for optimal printing parameters is a renown problem. This two-parts paper proposes an easy-to-follow and low-cost procedure for the characterization of any given FDM machine. The method allows the evaluation of the effects of a wide selection of FDM process parameters on the quality of 3D printed parts. The first part focuses on the definition of a series of metrics to be measured on a series of test prints to evaluate the quality of the produced parts. Specifically, several effects are considered: dimensional accuracy, small details, overhang surfaces, ability of printing small holes/thin extrusions and overall quality of the prints. The evaluation of seven quality parameters on a single print is made possible thanks to: i) a specifically designed specimen that is made available to the user and ii) a rigorous and repeatable measurement procedure, which are both discussed in the first part of the paper. The second part presents the characterization procedure, the statistical tools used in the experimentation and provides guidelines to be used for the characterization of any FDM machine. The whole procedure is tested on a desktop FDM machine to demonstrate obtainable results.

This constribution presents the engineering design of the non-conventional shearing device, which uses for the operation the magnetic field. There is a prototype of the device designed and constructed in laboratory conditions. There are presented all relevant and necessary data of this shearing device supported by figures and scheme. The principle of the device operation consists in the fact that a sheet passes through feed rollers into the shearing position, i.e. into the position between two blades. Lower is fixed and the upper is guided in rails and controlled by means of springs. After the material dividing the electric circuit is interrupted and the moving blade returns into the starting position due to spring's action. This process of metal shearing can be quite simply automated. We have performed same experimental works using this device. There were sheared same sheet samples and the comparision of surfaces are shown. The use of our our device has proven to be appropriate for shearing sheets made of aluminium alloys with the thickness of 0.3 mm.

This paper describes selected aspects of design, optimization and manufacturing process of racing car's upright. Uprights described in this paper are formula student car's uprights. Formula Student is an international competition between university students, which must design and build a new prototype of the car each year, according to the FSAE rules. Uprights for most racing cars, formula student cars included, must meet wide specter of different requirements, like minimal weight, minimal stiffness etc. The first part of this contribution is concerned to design requirements and boundary conditions definition problematics like different uprights types. The following parts describe the material selection and possible optimization for the design and manufacture of the new uprights for the formula car. Manufacturing and final assembly of the part will be described.

Additive Manufacturing has enabled the design of complex components in several technical fields. Considering turbomachinery components, additive manufacturing has unlocked the achievement of significant performances for dynamic rotoring components. The application of topology optimization methods is one of the main factors accelerating the technological development of this sector. This paper presents a procedure for the optimization of static turbomachinery components. The frame-work proposed compares the results obtained by introducing a lattice structure and a solid optimized shape. The procedure is presented with reference to a specific case study. To validate the proposed framework, the complete re-design of a thrust collar of a major Italian-based Oil&Gas company is carried out, demonstrating that the re-thinking of the component in terms of Topology Optimization is a straightforward approach to increase the overall performance of the produced part.

The quality properties of high pressure die casts are closely correlated with porosity. The formation of porosity is primarily initiated by entrapment of air and gases in the volume of the melt, during its transition through the gating system. This entrapment can occur as a result of an incorrect design of the gating system, incorrect setting of the casting technological parameters, or sometimes a combi-nation of both causes. The setting of the piston velocity in the first and second phase of the casting cycle has the highest proportion of the gas entrapment of all the technological parameters. The sub-mitted article is describing the influence of piston velocity in the first phase of the casting cycle. Ve-locities are investigated in range from 0.1 m.s-1 to 1.3 m.s-1. First of all, the development of the wave arising at different piston velocities is assessed and the gas entrapment in the melt volume is investi-gated. Subsequently, the proportion of the gas entrapment in the cast volume at the end of the filling phase is investigated depending on the variable value of the piston velocity in the first phase. In the end, the determination of the piston velocity impact in the first phase on the completion nature of the filling chamber of the machine is derived.

Concurrent engineering plays an important role in manufacturing. Cooperation among all factors relating to the realisation of products is now necessary. Production costs represent about 40% of the selling price of products and therefore design for production and for other aspects is very important

The third generation aluminium-lithium alloy AA2050 finds wide applications in defence and aircraft industries by virtue of its high strength-to-weight ratio and excellent corrosion resistance. Friction stir welding (FSW), relatively novel technique, is more suitable to join this alloy compared to other conventional fusion welding techniques. In this work, the overall quality of the weld joint was decided from the higher values of tensile strength, yield strength, percentage elongation, hardness of weld zone, hardness of heat affected zone, bending load and lower value of width of heat affected zone. The optimal (combined) design was used to design the experiments with four numeric factors (traverse speed, rotational speed, tilt angle and shoulder diameter) and a categoric factor (tool pin profile). The multi-response optimization problem was reduced into a single-response optimization problem using grey relational analysis (GRA); principal component analysis (PCA) was used to assign optimal weighting values for the responses in the process of dimensionality reduction. Mathematical model for the reduced single response, which can be perceived as overall weld quality, was developed by the response surface methodology (RSM) and the optimization of process parameters was also carried by the RSM. Analysis of variance (ANOVA) was carried to evaluate the significance of each parameter on the overall weld quality and the adequacy of the developed model. The confirmation tests conducted at optimum levels of parameters proved the effectiveness and robustness of the method.

Like most new technologies, 3D printing has long been a domain of narrowly specialized fields. However, the potential of this technology is enormous and thus it has been gradually finding its application in ever-newer sectors. This paper focuses on the structure and overall implementation of a triaxle manufacturing device inspired by an existing 3D printer design based on the modular RepRap concept. The result is a functional triaxle manufacturing device capable of performing 3D printing and laser cutting or laser engraving.

Various structure states before quenching significantly influence final mechanical properties as well as the dispersion of chemical composition at the same steel grade. Therefore heat treatment with mechanical properties is specified in the technical delivery conditions. Even if the heat treatment is determined, different mechanical properties can be achieved. These differences are increasing in im-portance in high-strength applications like springs, cutting tools, safety, and load-bearing parts of automotive design et al. Because it has a direct impact on their lifetime. The structure consists of ferrite and cementite after spheroidization annealing prior quenching process. The cementite could be observed in various shapes, e.g. fine and large globular particles or the rest of the disintegrated lamellar shape. This article shows how these cementite morphologies affect the quenching behavior and final mechanical properties in high-strength spring steel 54SiCr6.

In view of the linear motor servo control system has the advantages of high speed, high response characteristics, in order to adapt to the motion precision, response speed and stability requirements of high precision movement occasions, combined with fuzzy control theory, the design of linear motor platform servo control system fuzzy adaptive PID control algorithm. At the same time, based on LabVIEW software, combined with USB-6009 data acquisition card produced by NI company, the experimental platform for linear motor motion control is designed. Through simulation experiments, the position tracking accuracy, disturbance resistance and response speed of linear motor can be greatly improved. The experimental results achieve the expected control effect, which provides a control method for related research. Therefore, the fuzzy adaptive PID composite control can combine the advantages of both and improve the control effect.

To investigate the effect of slow tool servo turning process parameters on surface roughness, we es-tablished a high precision surface roughness prediction model. A guide to the selection of turning process parameters was compiled, and a turning test was conducted based on a response surface method (RSM) central composite design. ANOVA explores the influence law of process parameters on surface roughness. A RSM BP neural network model, and MEA-BP surface roughness model were established and the prediction performance of the three models was evaluated. The results show that the significant process parameters affecting surface roughness are tool radius, discrete angle, feed rate, and cutting depth in descending order; and the prediction errors of RSM, BP, and MEA-BP are 11.41%, 19.67%, and 5.54%. This suggests that the MEA-BP model has the highest prediction accura-cy with the same test data, RSM is second, whilst the single BP model struggles to capture multiple data characteristics and its prediction accuracy is poor. In addition, MEA can effectively solve the BP model falling into local optimum and improve the model prediction accuracy.

The aim of the article is to analyze the friction welding process of steel pistons, due to the small amount of scientific literature on this subject. First, it is necessary to present the design fea-tures of steel pistons and their advantages and disadvantages. Then analyze the types of friction weld-ing processes used in the production of pistons of internal combustion engines with the analysis of their differences. Present two basic methods of welding in the production of steel pistons, i.e. friction butt welding and low pressure friction welding. Finally, a proper analysis of the friction welding pro-cesses of steel pistons of internal combustion engines can be presented. At the end, the conclusions of the analysis are presented and proposals for improving the process are made.

The paper describes the experimental validation of the biomechanical response of the Hybrid III 50th Percentile Male Pedestrian Dummy (JASTI, Tokyo, Japan) at low impact velocity (up to 2.2 m/s) in comparison with that of human probands. The paper is based on previous research that was focused on the tram-pedestrian crash tests using the same dummy. The biofidelity of the dummy was analyzed in two collision scenarios: the anteroposterior impact (chest impact) and lateral impact (shoulder impact) using a unique pendulum impact testing machine of own design and construction. The primary outcome variable was the peak resultant acceleration of the head and chest during the impact. Based on the lab-based measurements, the unique impact testing machine was found adequate and precise for the purposes of future crash-test analyses in the area of the automotive industry. The proposed methodology and measurement protocol were shown proper to compare the data between the dummy and human participants. Following the pilot experiments, the kinematic and dynamic data between the dummy and human participants were analyzed to assess the biofidelity of the dummy for the frontal and side impact during tram-pedestrian collisions at low impact velocities.

Abstract: The article describes a new technical solution for ensuring efficient and inexpensive cleaning, disinfection and sterilization of production facilities and their equipment, based on the principle of gen-erating the use of ozone gas. It describes the technical solution and construction of sterilization and cleaning equipment with ozone gas and the sterilization of small objects, especially textiles contaminat-ed with various viruses, including the Covid-19 virus. The device is designed as energy-saving, structur-ally simple, with high sterilization and cleaning efficiency. The sterilization device is small in size, mo-bile and its design enables transportation in the trunk of an ordinary passenger car. The weight of the device is 14 kg. The device's ozone source is an ozone air purifier, mass-produced according to valid EU standards. The power source of the ozone purifier is an electrical source with a voltage of only 230 V and a frequency of 50 Hz. Alternatively, it is possible to use power from a safe mobile source or inverter. The operation of sterilization and cleaning device in a closed, non-ventilated area, does not endanger peo-ple's health or damage plants. The description of the construction of a technical sterilization device is focused on a specific type of device, but the stated theoretical results can be equally well used in the electrotechnical, food, medical or pharmaceutical industries and in general wherever there is a need to effectively and efficiently clean and sterilize production objects, their equipment, used materials and all other production aids means and tools.

In order to accumulate experience in the design and manufacturing of the toroidal field coils for the China Fusion Engineering Test Reactor, a model coil of mixed Nb3Sn-NbTi superconducting magnet with a maximum magnetic field variation rate of 1.5 T/s has been developed at the Institute of Plasma Physics, Chinese Academy of Sciences. The preload system, as one of the key components of the model coil, plays a crucial role in maintaining the overall integrity and stability of the model coil. First the magnetic field and electromagnetic forces of the model coil under extreme conditions are calculated based on Maxwell's equations. Then, the mechanical performance of the model coil at room and cryogenic temperatures is analyzed. To addressing the issue of excessive stress in the preload components of the model coil under preload, several optimization design schemes are proposed and iteratively analyzed. Finally, stress linearization is performed, and stress evaluation is conducted based on the analytical design. The assessment results indicate that certain optimization schemes enable the preload components to fully meet the operational requirements at both room and cryogenic temperatures. The outcomes presented in the paper will provide reference for the subsequent design and manufacturing of the central solenoid coil.

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.

In order to test whether the design of the new steel mold trolley meets the requirements of the working conditions,the ANSYS finite element simulation and optimization analysis of the frame system of the new steel mold trolley were conducted.After the analysis, the results show that the new steel mold trolley designed basically meets the requirements of strength and stiffness, but there are some problems of insufficient strength；Through the topology optimization of the gantry frame of the new steel mold trolley frame system, the "door shape" section gantry structure with better force structure was obtained.The influence of the specific structural parameters of the "door shape" cross-section gantry structure on the overall stress of the steel mold trolley frame system was studied.The results show that the optimized steel mold trolley gantry structure has a maximum stress of 174.94MPa, an average stress of 26.22Mpa and a maximum deformation of 2.20mm under the condition of extreme load, which can better meet the actual engineering needs.

Cast iron with nodular graphite is one of the most important structural materials that exhibit really good mechanical properties already in the as-cast condition. Nowadays, cast iron with nodular graphite is used in many areas of the manufacturing industry, the most widespread being in the engineering and automotive industries. The applicability of this material for construction purposes is mainly due to its mechanical properties, which are close to those of steel, but the production cost of cast iron is lower. This experiment was aimed at optimizing the production of ductile iron castings in the casting pits so that the foundry could produce ductile iron castings in the casting pits. Therefore, the optimization of the moulding compound database material was carried out in numerical simulation and at the same time, the heat transfer measurement of the foundry sand mould was carried out.

Optimising the mechanical properties required for biomedical applications is something that porous Ti-6Al-4V structures offer the opportunity to do. Triply periodic minimal surface (TPMS) structures, such as the Diamond and Gyroid structures, provide interconnected pores that can be used to adjust strength, stiffness and deformation. The mechanical behaviour of these two architectures under compressive and bending loads is compared in this study, with the use of additively manufactured samples. The results demonstrate that pore geometry significantly impacts mechanical behaviour. Diamond structures exhibit higher stiffness and strength, whereas Gyroid structures provide a more isotropic and flexible response. These findings emphasise the importance of architecture when designing implants and other components for which optimised mechanical properties and geometry are essential.

This paper investigates the replacement of a conventional steel coil spring with a composite disc spring with the aim of minimizing its weight. Simulation in the CAD system Siemens NX 12 was used to determine the composite disc spring’s behavior. The regression functions were stated based on the numerical simulation. Based on the regression functions the solution with the minimum weight was found using software programmed in Matlab. The prototype discs were manufactured from carbon fibre prepreg. Their load-deflection characteristics were tested and compared with the designed values. The experimental results show that using this solution reduces the weight by about 30% in this case.