bluuebunny/crossref_metadata_2025_split huggingface dataset:
The modelling of detached chip area at square shafts machining with rack tools
Authors: Bordeanu M , Frumuşanu G , Oancea N 
Published: January 2021

Abstract
The paper deals with analyzing, by 3D modeling, the shape and the area of the chips detached during the machining of shafts with square cross section, by slotting with a rack tool. The proposed modeling requires at first to determine the tool profile. This step is accomplished by finding the equations of the surfaces family described by the tool relative to workpiece, and by using the enwrapping condition, written according to Minimum distance theorem. The generating process is modeled then, on the base of CATIA environment facilities, aiming to find, in graphical manner, the variation law of the detached chip. Solving this problem could be a primary level of analysis needed for designing the hobbing tool used for machining the same type of part. A numerical and graphical application of the proposed modeling algorithm is also included. The final goal of the research is to deliver the necessary information for smoothing the addressed machining process by modifying the kinematics of the generating process.
Estimating the warranty returns and proving root causes using statistical analysis of archived parameters measurements for an automotive mechatronic device
Authors: Braga I C , Udroiu R , Nedelcu A 
Published: January 2021

Abstract
In the mass production of the automotive industry, there are many cases in which a problem is not detected in the production processes of the supplier, but after delivery, in the customer’s assembly line. As a result, it is necessary to know both root causes to prevent them, but especially, if it cannot be detected even in the customer’s processes, to estimate the probability of occurrence in the warranty period. The paper’s aim is to present the analysis of the measurements of the mechatronic devices indirect parameters linked with the effect of the failure and by statistical correlation to prove the root causes. A study case will be used to understand the failure first occurrence and the duration of its effect, as the symptom description as well, in that way it will support the estimation of the warranty return number of parts, eventually, the accounting department can establish the provisions based on the output data.
Study upon the kinematic simulation of the incremental forming carried-on using a serial industrial robot
Authors: Breaz R E , Racz S G , Girjob C E , Tera M 
Published: January 2021

Abstract
Incremental forming with contact between tool-sheet metal workpiece in a single point is an unconventional process which allow the user to manufacture parts by combining the vertical movement of the tool along Z-axis and the horizontal movements of sheet metal workpiece, which are performed in XY plane. As technological equipment able to control coordinated movements on three axes, CNC machining centers and industrial serial robots with six degrees of freedom are the most suitable. The paper introduces a study regarding the use of robots as technological equipment for the process, by means of simulation. Supplementary degrees of freedom and singularities avoidance are also considered.
The optimization of cutting parameters at turning, using electrical current at cutting, in order to increase the durability of the cutting tool
Authors: Daicu R , Diţu V 
Published: January 2021

Abstract
The optimization of the turning cutting parameters was a permanent concern for research but also for production. The emergence of new metal materials to be processed as well as the development of new cutting edges has always led to new optimizations of the cutting regime. The appearance of coated plates, single layer or multilayer, determined the companies producing them to indicate information about the cutting parameters, but the values are given in a certain interval. In order to reduce the necessary experiments to indicate the optimal cutting regime, the paper proposes the analysis of the electrical current at cutting and its use for optimization. The processing of the experimental data obtained as well as the optimization of the cutting parameters was performed using Design Expert software.
Simulation research on pressure shock of load sensing system of large boom tower crane
Authors: Fei Y , Li J , Sun C 
Published: January 2021

Abstract
Large boom tower cranes have large masses, heavy loads, and large inertial dynamic loads during the conversion of working conditions. Even if there is a buffer device, hydraulic shock will still occur. The problem of hydraulic shock seriously affects the leakage of hydraulic oil and decreases system reliability. Now the closed hydraulic system of a certain type of boom tower crane is taken as the research object, and the joint modeling of machinery and hydraulic is completed in AMESim. Without changing the basic hydraulic components, the hydraulic system of the whole machine just adjusts the ratio of the pulley block or changes the hydraulic speed regulation method to study the hydraulic shock of the servo-sensitive hydraulic system. AMESim simulation results show that in this load-sensitive system, the double-rate hoisting of the pulley block is compared with the single-rate hoisting of the pulley block, the maximum dynamic load generated by the load off the ground is increased by 5.4%; Speed regulation of the variable pump and variable motor combination is compared with the speed control of only variable motor, the maximum dynamic load of the hydraulic system is reduced by 7.6%.
Analysis of the influence on the hydraulic lifting circuit of the boom crane when the characteristics of the steel wire rope changes
Authors: Fei Y , Jiang J , Sun C 
Published: January 2021

Abstract
In the process of lifting and landing of large hydraulic crane fully loaded, the working condition conversion makes the stress of steel wire rope change frequently and generate additional dynamic load, which makes the movement of the crane unstable and affects the working stability of the hydraulic system, and also leads to the fatigue damage of the tower structure and reduces the effective working life of the tower crane. In order to find the optimal dynamic characteristics of hydraulic system, the initial tension force, stiffness of hoisting wire rope and rigidity of variable amplitude wire rope of hoisting wire rope are studied respectively by means of machine-liquid integration simulation based on the AMESim, a kind of simulation software. The lifting mechanism of a type of closed hydraulic system is modelled and simulated. The results show that the maximum dynamic load of hoisting mechanism is reduced by 92.6% and the stabilization time is reduced by 49%. The optimized stiffness of hoisting wire rope reduces the dynamic load and peak pressure of hoisting mechanism by 5.2% and 4.3% respectively. The stiffness of the variable amplitude steel wire rope has little effect on the dynamic characteristics of lifting.
Application of fractal theory in fault diagnosis of nonlinear mechanical equipment system: a review
Authors: Hou X L , Wang X 
Published: January 2021

Abstract
Fractal theory takes the irregular and complex things as the research object, and uses the fractal dimension to describe the object. The review classifies and summarizes the application development of fractal theory in the diagnosis of common nonlinear mechanical equipment system faults such as diesel engines, gear boxes, hydraulic systems, etc. It is showed that fractal theory can extract and analyse irregular features and simplify complex research. It has certain advantages among various methods and is gradually being widely used. It provides a new reference and idea for the future research direction after fully understanding its current status and summarizing its characteristics. At present, most of the research on fault diagnosis of mechanical equipment is based on the signals under steady running state, while ignoring the transitional signals with high information content. Fractal theory has unique advantages in dealing with this kind of transitional signals such as the start and shutdown of equipment. It is a new trend to solve practical problems that study the short-time signals at transition process with strong non-linearity based on fractal theory to diagnose the fault of the mechanical equipment.
Voice frequency impact for voice control of collaborative robots
Authors: Janíček M , Holubek R , Ružarovský R , Velíšek K 
Published: January 2021

Abstract
The project is focused on research of voice control of collaborative robots. Previous research of voice control and speech recognition research have given examples and evidence that machines can truly be controlled by human voice. The main problem in the voice control of collaborative robots is the lack of reliability and safety of control compared to manual control. Of the results achieved, the most and least relevant voice control problem has been clearly identified, next step is voice frequency impact for voice control. The experiments were performed in the robotics laboratory at the Faculty of Materials Science and Technology in Trnava, and this using an Arduino kit and a small robot “DOBOT Magician“. In the final part of the project are summarized all experimentally found facts and confronted with the assumptions set in the design of the experiment.
Study of milling machining roughness prediction based on cutting force
Authors: Kao Y C , Chen S J , Vi T K , Feng G H , Tsai S Y 
Published: January 2021

Abstract
Cutting parameters can to be properly adjusted to increase machining precision, to enhance cutting efficiency, and to reduce cost. These parameters are generally chosen according to the recommended data from the tool maker’s technical manual with the synergy of the operator’s experiences. However, inappropriate parameters selection might not only damage cutter and the machine tool, but also worsen the surface roughness of the workpiece. Researches on improving surface roughness has been studied over the years, for example, on the optimization of cutting conditions, vibration measurement and analysis, and cutting forces measurement and analysis, to name only a few. However, most of them must have sensors installed on the machine tool for data collection before the analysis. This will increase the cost. Furthermore, the measurement of cutting force needs to have dynamometer which is not only expensive but is also not appropriate to be installed on a small-sized machine tool. This research focused on establishing the relationship between the cutting force and the surface roughness for the workpiece machining in a small-sized machine tool. In order to calculate the cutting force, cutting force coefficients were obtained based on the cutting test on the other machine tool rather than the small-sized machine. Tapping test was also conducted to obtain the frequency response function of the machine. The cutting forces were calculated based on the cutting force coefficients and the frequency response function. The calculated cutting forces were then converted through the proposed methodologies into eleven characteristic values. Finally, two commonly used machine learning algorithms, multivariate linear regression and generalized regression neural network were adopted for regression analysis to establish the relationship between the cutting forces and the surface roughness. The results have shown that the prediction by generalized regression neural network is better than that of multivariate linear regression. The major contribution of this paper is that appropriate algorithms have been studied, compared and verified so that the relationship between cutting force and surface roughness can be established. This means that surface roughness can be estimated based on the calculated cutting forces incorporating the machine tool’s frequency response function.
Prediction of radial clearance based on bearing vibration using artificial neural network
Authors: Knežević I , Živković A , Rackov M , Kanović Ž , Buljević A , Bojanić Šejat M , Navalušić S 
Published: January 2021

Abstract
Artificial neural networks are used for diagnosing of ball bearings condition. They are capable to recognize bearing fault from information extracted from signal of vibration. The aim of the work is to investigate the relationship between vibration velocity in the characteristic band frequencies and radial clearance. Changing the radial clearance during operation may indicate changes in the operation of the rotating system. Experimental research is based on deep groove ball bearings and measuring the vibration of the bearings. The vibration velocities for each bearing were measured under laboratory conditions, and the processed signals were used to train the artificial neural network. An artificial neural network trained in this way can predict the size of the radial clearance based on the vibration of the bearing.
Fabrication and service of all-ceramic ball bearings for extreme conditions applications
Authors: Li S , Wei C , Wang Y 
Published: January 2021

Abstract
Hot isostatic pressing silicon nitride material has properties that most metal materials do not have, such as low specific gravity, high strength, high stiffness, wear resistance, corrosion resistance, extreme temperature resistance, electrical insulation, no magnetic permeability, and excellent dimensional stability Performance, self-lubricating performance, etc. It is one of the ideal alternative materials for the manufacturing of bearings applied to various extreme conditions. This manuscript focuses on the practical needs of bearings for environmental equipment such as extreme temperature and marine corrosion. These bearings are used to improve the ultimate speed and load capacity of the whole steel bearing design system in ultra-high speed applications (such as machine tool spindle and gas turbine engine); to eliminate corrosion and reduce friction under extreme temperature or corrosion conditions, so as to improve system performance. In this paper, from the preparation of ceramic bearing materials to the ultra-precision machining process of ceramic bearing components, the development status of ceramic bearings in recent years is introduced, and the future development and application prospect of ceramic bearings are prospected.
A brief review of numerical simulation in process machining
Authors: Malea C I , Nitu E L , Iordache M D 
Published: January 2021

Abstract
Machining is a technological process that involves removing the material by generating chips, aiming to obtain flat, cylindrical, helical surfaces etc. This processing method is widespread in the industry and it is, therefore, necessary to define appropriate technical and economic solutions concerning the materials and geometry of the tools, the orientation and fixture of the devices, and the machine-tool used. It is also particularly important to use the most appropriate cutting parameters for modern industrial applications. Scientific research addresses these issues through analytical, semi-empirical, or numerical modeling. Numerical modeling and simulations can satisfy with very good precision the solutions of these aspects, with diverse methods and techniques used in the study of the cutting simulation. This paper presents an analysis of recent studies, briefly presenting the main approaches and techniques used in numerical modeling and simulation of machining. The input parameters, components, and output parameters of these numerical models are identified as well. Finally, the advantages and disadvantages of using these methods and techniques are summarized, as well as the problems to be developed in the area of numerical modeling and simulation of cutting processes.
A comparative assessment of reliability indicators and parameters of the bearings using different estimation methods
Authors: Morariu C O , Zaharia S M 
Published: January 2021

Abstract
The paper depicts the method of statistical processing of experimental results, obtained by testing bearings on the test stands, using the maximum likelihood estimators and/or Best Linear Invariant Estimator. To verify statistical assumptions regarding parameters and reliability indicators of bearings, as well as, to determine confidence intervals, the article contains two original algorithms that allow obtaining values of some specific random variables by Monte Carlo numerical simulation. The statistical inferences are made through these values. The paper also, contains two case studies using data from failures and time truncated tests of bearings.
The methodology of economic recovery of commercial companies in crisis conditions
Authors: Panazan O , Gheorghe C , Calefariu G 
Published: January 2021

Abstract
Even though commercial companies play a really important role in the economic functioning and development, now, in crisis conditions, the future for some of them is unknown. As a result of the release of crisis caused by „Coronavirus severe acute respiratory syndrome 2, abbreviated SARS-CoV-2”, these companies are facing novel negative situations, not being able to manifest temporarily or normally the activity. From a systematic point of view, this crisis has the role of a really powerful disturbing factor. The creditors and investors are in a similar fragile situation. This paper identifies some scientific methods which can decrease the negative appeared problems, building models that take into account the limited resources that companies face and that they can lead to improving their economic situation. As an application, part of the essay presents the synthesis of the main assets and malfunctions of a company established in Romania. The elaboration of future strategies will be achieved through the systematic research of the admissible bases, aiming at maximizing the objective function. The type of equilibrium by reverse induction will be established, thus obtaining the set of the best cost variants. Linear programming will generate the optimal solution capable of exploiting the opportunities offered by the market with a minimal impact of disruptive factors.
An approach regarding some performances of a FESTO pneumatic muscle actuator
Authors: Petre I M 
Published: January 2021

Abstract
This paper presents some performances of a pneumatic actuated artificial muscle, manufactured by FESTO. Pneumatic muscles are novel actuators, constructed by an elastic membrane covered with a braided mesh, based on a contraction principle: inflated, it shorts its length with a certain dimension depending on the compressed air pressure. Those muscles are known for their wide application in industry and robotics, as actuators. The aim of this study is to find operational behaviour of a pneumatic muscle. Some experiments was made, in order to prove the maximum contraction of the muscle, the evolution of the contraction at different pressures and loads. The results obtained are graphical plotted. Based on the obtained results, it was made an analysis and identified the best fit equation for the data. The experimental research carried out highlighted that the pneumatic muscles offers many advantages and disadvantages in terms of their behaviour in operation.
Mobile emergency notification apps: current state, barriers and future potential
Authors: Repanovici R , Nedelcu A 
Published: January 2021

Abstract
The main objective of this research is to show that mobile emergency alert apps have the potential to support the Emergency Management system all over the world. Domain experts conducted the decision-making process by evaluating three methods for communicating in an emergency situation: Voice Call, SMS and Mobile Applications. To establish the relative weights of evaluation criteria, the Multi-Criteria Analysis was used. The findings suggest that the ideal solution for communicating during an emergency is alternative no. 3, the Mobile Application. Following the result, we discussed the current state, barriers and future potential of mobile emergency alert applications used for emergency notifications.
Study of the deviation of shape for the parts obtained by additive manufacturing
Authors: Rizea A D , Anghel D C , Iordache D M 
Published: January 2021

Abstract3D printing or additive manufacturing is a parts manufacturing process using a digital model can be drawn using suitable computer aided design (CAD) They can be created using 3D printing products of almost any shape. This article presents research concerning the deviation in shape of the parts obtained by additive manufacturing (3D printing). The digital model was made with Catia V5 and was imported by the 3D machine software to obtain the prototyping codes for nine specimens. The specimens were made according to a Taguchi L9 plan. On the basis of the code obtained with the printer software, the parts have been prototyped, using the Z-ULTRAT material with a ZORTRAX M200 printer. The input data that were varied are: layer thickness, infill and orientation. For each part obtained by 3D printing were measured: circularity, flatness and dimensional accuracy. All parts were measured and a database was created and following the regression analysis performed with the Minitab19 software was establish the influence of the parameters on the deviations and dimensional accuracy.
Making Industry 4.0 functionalities understandable based on the production of a model car
Authors: Roman S , Bunsen C 
Published: January 2021

Abstract
At the University of Applied Sciences Würzburg-Schweinfurt, Faculty of Mechanical Engineering, an Industry 4.0 use case was implemented with the c-factory, the so-called concept factory. This use case consists of building an individual model car. The focus here is not on the model car, but rather on mapping the entire product life cycle and the Industry 4.0 functionalities during the production. These are, as identified at the FHWS/FM: networking, the Internet of Things, flexible production, human-robot-collaboration, augmented reality, additive manufacturing and Big Data. The foundation stone was laid as part of a student project and, with its unique form of enabling didactic, serves not only to demonstrate and understand Industry 4.0, but also ensures that all participants take on the role of both learner and teacher. Through this, both sides support each other in expanding the use case and hereby broaden their own (educational) horizons.
Generation of precessional gear teeth by plastic deformation
Authors: Trifan N , Ciobanu R , Ciobanu O 
Published: January 2021

Abstract
The correct choice of the dimensions of the workpiece product is one of the main problems, the solution of which depends on the reduction of the consumption of materials and energy, as well as the quality of the wheels obtained by plastic deformation. Referring to the manufacture of conical wheels with convex-concave profile of the teeth by knurling, the height of the teeth is determined by the condition of the equal volume of metal that moves from the gaps between the teeth to their tip during the plastic deformation by rolling. The use of methods for the manufacture of teeth without chipping will allow the increase of the utilization coefficient of expensive materials.