AutoCAD Environment Research Articles

Micro geometry analysis of WC-Co carbide blades modified with PVD coating subjected to blunting during milling in chipboard

ABSTRACT In this work, a number of geometrical parameters related to the microgeometry of the cutting edge, such as rounding radius r, maximum clearance wear VBmax and a number of others, were determined. Tools for processing wood materials made of WC-Co cemented carbide with a PVD coating based on Ti and Al. were blunted until the wear indicator VBmax reached the value of 0.2 mm. The cutting blades prepared in this way were tested using a contact profilometer. Based on the data obtained in this way, an analysis of the blade contour over a length of 10 mm was carried out in the AutoCad environment. This section included both the blunted part and the part not involved in the cutting process. Correlations obtained using a procedure written in Visual Basic for Applications using elements of statistical data analysis built into the Excel program, between the selected rounding asymmetry coefficients denoted with letter K and the blade wear indicators proposed in the tests were analyzed. Geometric indicators were also determined, taking into account the working conditions of the tool, affecting the process of its blunting, such as e.g. h (uncut chip thicknesses).

Visual Basic Drawing Codes from 2D AutoCAD Drawings andVisual Basic Drawing Codes from 2D AutoCAD Drawings and Machine Parts Applications

It is of great importance to support vocational programs with graphics. Before the necessary graphic codes are written, drawings are usually prepared in the CAD environment. Then, graphic coordinates are taken from the drawing environment and software graphic codes are prepared. This situation requires a lot of effort and time. In this study, a software has been developed in AutoLISP programming language, which converts drawings in Autocad environment into Visual Basic drawing codes in a very short time. The use of mechanical engineering drawing codes produced with the developed program is shown in visual basic environment with animation support. The conversion of bolts, radiused parts, gear and propeller drawings in Autocad environment into Visual Basic codes and program examples are shown in the software developed in this study. It is expected that the developed program will save time and effort in writing the graphic codes to be used in new program designs. Keywords: AutoLISP, Visual Basic, Autocad, Simulation, Software Development DOI: 10.7176/JIEA/13-2-04 Publication date: March 31 st 2023

GEOMETRIC SIMULATION OF THE MOVEMENT PROCESS OF THE EXCAVATOR’S MILLING WORKING EQUIPMENT

The simulation of the process of movement of the milling working equipment of an excavator when digging a pipeline is discussed. The parameters of the repair and construction strip are calculated, the position of the coordinate systems of the excavator manipulator mechanism is established. A hypothesis has been put forward that the position of the excavator on the strip affects the volume of movement during digging, which increases energy consumption and reduces economic efficiency. The excavator manipulator is considered as a five-link mechanism. A kinematic scheme of the mechanism is given, on the basis of which a program based on the synthesis of movements along the velocity vector is created. The construction of the movement trajectory was carried out in such a way, that the output link was in a horizontal position throughout the entire movement process. The program was created using the Visual Lisp programming language built into the AutoCAD environment. The program made it possible to obtain graphic models of the movement of the excavator manipulator mechanism in its various positions, as well as to calculate the amount of movement. Based on the data obtained, a drawing by Radishchev was constructed, which reflected the dependence of the generalized coordinates of the excavator manipulator mechanism and the amount of movement on the depth of lowering of the working equipment. As a result, it was concluded that with the middle position of the excavator on the traffic lane, a smaller amount of traffic is provided, which means less energy consumption and a higher speed of work. The results of the conducted research can be used in the design of software and hardware systems for controlling moving objects, in particular, control systems for the motion of an excavator manipulator.

Design of A Water Transmission and Storage System for Sustainable Reuse of Wastewater Within A University Community

This research is aimed at designing a wastewater transmission system from storage to treatment and, eventually to storage in an elevated steel tank. The work includes the design of a 750,000-litre capacity underground concrete reservoir and a 125,000-litre capacity elevated steel tank. For the transmission design, field activities involved the use of Magellan eXplorist 350H North America G.P.S. and Google Earth to determine coordinates of different points in a selected private university campus, southwest Nigeria as well as the lowest and the highest elevation points. The highest point in the university was located at the postgraduate hall of residence, and the lowest point was located at the schools constructed wetland within the campus. WaterCAD was used to design the flow path network, while the water storage design software used for this project are StaadPro.V8i, Orion 18, and AutoCAD 2013. StaadPro.V8i was employed for the analysis and design of the underground storage facility and the elevated steel tank, while the Orion software was utilized for concrete design and detailing of the underground storage facility. The results from all the design applications were exported to the AutoCAD environment for editing and proper scaling. This study has revealed that the construction of a 750 m3 underground storage tank would be highly efficient and economical when compared to a smaller tank. Also, both the hydrostatic forces acting internally within the underground tank and active and passive pressure acting externally toward the wall has shown to possess zero impact on the shear wall.

Visualizing surface formation of semi-regular polyhedra of Archimedes

The most common method of forming semi-control polyhedra consists in cutting off angles and ribs of regular polyhedra by planes. The aim of the work - to consider the automated formation of a number of surfaces of semi-regular Archimedean polyhedra based on the dodecahedron. These include the truncated dodecahedron, the icosododecahedron, the romboicosododecahedron and the truncated icosododecahedron. The formation of surfaces is carried out by the kinematic method in AutoCAD using programs compiled in the AutoLISP language. Methods. The methodology for the formation of these polyhedra provides for truncation of the angles and edges of the dodecahedron. This requires the calculation of a number of geometric parameters of these polyhedra and dodecahedron, such as the value of the truncation of the dodecahedron edges, the size of the edges of truncated polyhedra, the centers of faces, dihedral angles, etc. In order to generate these surfaces, a frame is constructed because the frame lines are used as guides to form surfaces in a kinematic way. The electronic model of each polyhedron is constructed as a set of compartments of surfaces of all its faces, and each compartment is assigned to a certain layer of the drawing. The frame and electronic model of the polyhedra under study are formed by means of user programs composed in the functional language AutoLISP. The process of forming surfaces of selected polyhedra in the AutoCAD environment is provided by special programs that are also compiled in the AutoLISP language. Results. Software was created to demonstrate the process of formation of a number of Archimedes polyhedra on the monitor screen.

3D Modelling of Construction Objects Based on the Integrated AutoCAD System

Wide implementation of computer modeling of three-dimensional construction objects allows us to solve many technical, logistical and design problems. The development of a detailed electronic three-dimensional plan is a valuable virtual base that allows you to create, display and use for engineering purposes models of various types of engineering, telecommunications and computer networks, plan their construction, modernization and replacement. Connecting external databases to the electronic model allows you get a full specification of buildings, networks and any other objects, display a time record of repairs, replacements, etc. in addition, the 3D model allows you to enter the color differentiation of objects, which can give additional information, for example, the allocation of dangerous equipment (fire, explosive, etc.) in red or other color on the three-dimensional plan of the building. AutoCAD was selected to build a 3D model of the branched multi-storey building of one of the buildings of a modern University, which allows you to get accurate 3D models, has the means of obtaining sections and sections, and also provides a fairly realistic visualization. To obtain a 3D model of the University buildings, all the work was divided into the following stages: building two-dimensional electronic plans of each floor; building three-dimensional models of each floor; combining floor models into a common 3D model of the building. Models of buildings were created on separate layers, which makes it easy to turn off a particular layer, and to study the internal structure of buildings. The 3D model has real dimensions and is easily scaled. Engineering networks and other equipment items can be attached to the model elements in the future, and other tasks will also be solved, such as the location of fire-fighting equipment, escape routes, emergency exits, etc. When creating 3D models, we used the color differentiation of objects. We describe a mechanism for programmatically selecting objects by color in the AutoCAD environment, as well as a program that implements this selection mechanism using a data file with sequential access as an external database.

Parameterization for addressing tasks on flat lever mechanisms kinematic analysis in the AutoCAD environment

The objectives on identifying all the links’ position in a flat lever mechanism within the considered time period, as well as determining the values of displacements, speeds and accelerations for the mechanism’s characteristic points are applied in engineering calculations in the course of the mechanisms designing process. Conducting kinematic analysis using the graphoanalytic method is a fairly accurate and visual method in training, but it is quite time-consuming and contains a lot of routine operations. This paper demonstrates a solution enabling to significantly reduce the number of routine operations by creating a dynamic block for the mechanism’s initial position with the parametric dependencies setting up. Designing is performed in the AutoCAD environment. This solution will help to quickly and accurately build a set of the flat lever mechanism links’ positions and display the characteristic curves for angular coordinates "φ" and time “t”. The algorithm for creating such a block, as well as the features of working with parametric models are described. The proposed method allows to introduce the research elements in studying the discipline “Theory of mechanisms and machines”. By imposing dimensional and geometric constraints, one can trace their influence on changing kinematic diagrams of the path, speed and acceleration.

The Method of High Accuracy Calculation of Robot Trajectory for the Complex Curves

Abstract The geometric model accuracy is crucial for product design. More complex surfaces are represented by the approximation methods. On the contrary, the approximation methods reduce the design quality. A new alternative calculation method is proposed. The new method can calculate both conical sections and more complex curves. The researcher is able to get an analytical solution and not a sequence of points with the destruction of the object semantics. The new method is based on permutation and other symmetries and should have an origin in the internal properties of the space. The classical method consists of finding transformation parameters for symmetrical conic profiles, however a new procedure for parameters of linear transformations determination was acquired by another method. The main steps of the new method are theoretically presented in the paper. Since a double result is obtained in most stages, the new calculation method is easy to verify. Geometric modeling in the AutoCAD environment is shown briefly. The new calculation method can be used for most complex curves and linear transformations. Theoretical and practical researches are required additionally.

Modeling of the process of non-stationary heat exchange in the lining of a rotating unit

Rotating heat units, or rotary kilns, are widely used in many industries where they are used for heat treatment of bulk materials. The efficiency of use largely depends on the reliable operation of the main structural elements. This is especially true of the lining of the furnace, the reliability of which significantly affects the performance, safety and long-term and reliable operation of the furnace unit. Therefore, the work devoted to the improvement of the theoretical model of heat exchange in a rotary kiln is extremely relevant as it contributes to the intensification of its work and makes it possible to implement more intensive modes of operation of the heat unit. The calculation of the temperature regime in the lining of the rotating furnace and filled with the processed material is performed. The differential equation for no stationary thermal conductivity is used. Numerical calculation is performed iteratively using the finite difference method according to an explicit scheme. AutoLisp programs in the AutoCAD environment are used to visualize and display graphical information. The movement of the material is modelled by changing the value of the heat transfer coefficient to the inner surface of the lining in the place where it is located. This takes into account the movement of the material along the inner surface of the lining. The change in position depends on the speed of rotation and the amount of material. The shift of the material layer by the angle Δφ occurs after determining by iteration the total time period for which the indicated displacement occurs. At the beginning of the rotation of the furnace, the temperature of the lining area free of material is evenly heated to the maximum value. After contact of the lining with the material begins the redistribution of temperatures in the surface layers. The inner surface of the lining of the furnace is heated by a gas stream, and when it gets under the layer of material - is cooled to 1246 °C, compared with the initial 1465 °C. At the time of exit, the temperature of the lining rises quite rapidly, after which the temperature rise slows down. After one revolution, the lining reaches the initial temperature level. This phenomenon explains the essence of the process of heat recovery by lining. In general, the amplitude of temperature fluctuations on the outer surface of the lining is 218.7 °C. At the same time intensive change of temperatures promotes emergence of the largest gradients and accordingly thermal stresses especially in a zone where there is a processed material. The depth of penetration of the variable temperature into the lining is defined as the ratio at which the amplitude of temperature fluctuations is 0.01 from the amplitude of oscillations on the surface. It is possible to determine that in this case the temperature change occurs at a depth of up to 70 mm, with a total lining thickness of 230 mm. The layers of the lining, which are deeper, have significantly smaller temperature fluctuations. Determining the intensity of heat flow allows to characterize the influence of technological parameters of the unit on the temperature and thermal regime of the lining and the rotary kiln as a whole. Analysis of the data of temperature fields and heat flux shows that the output to the quasi-stationary heat regime occurs after 4-5 revolutions of the furnace. The result of this research is the development of a mathematical model, algorithms and software for calculating and studying the process of non-stationary heat transfer in the lining of rotating units. Numerical calculations are performed and the evolution and distribution of temperatures and heat fluxes in the lining are determined. The depth of penetration and the amplitude of alternating temperature fluctuations that lead to the destruction of the surface layer of the lining refractorines due to thermal stresses are determined. The results of the calculation are also given in the electronic appendix to the article in the form of video files.

CAD Based Electric Transporter Path Planning and Production Storage Optimization Using Genetic Algorithm – Industrial Case Study

Štore Steel Ltd. is one of the largest flat spring steel producers in Europe. There are two production lines after rolling – one for flat bars and the other for round bars. The flat bars production generally consists of visual examination, straightening and cutting operation. In addition, heat treatment or magnetic particle testing could be conducted. On the other hand, the round bars production consists generally of straightening, automatic control line control, chamfering and cutting. In addition, heat treatment is possible. For manipulation of the material in the rolling plant, the electric transporter and several cassettes are used. In the paper path planning and production storage optimization (i.e. storage spaces for cassettes) were conducted using genetic algorithm. The production storage is actually the space between main transport passage and individual operations. In the research the universal system using CAD geometry is presented where AutoCAD environment and in-house developed AutoLISP system were used. The production storage – storage spaces for cassettes (location and orientation) with corresponding electric transporter trajectories are represented as CAD objects and thus form individual solution/organism. The organisms undergo simulated evolution. The results of the evolution are compared with actual production storage in the steel plant.

Hydrological and Hydraulic Analyses of Urban Storm Water Drainage System of Major Area of Pokhara, Nepal

The immense increase of the structural activity which decreases the pervious area of the city is alarming danger situation pertaining to drainage. Urbanization and improved area of imperviousness are the major contributors that make the existing drainage network insufficient while inadequate maintenance and haphazardly throwing rubbish on the road and drain are other issues. The major objective of the study is to analyze the hydrological and hydraulic status of the urban storm water drainage system of the major area of Pokhara City of Nepal and to compare the calculated result with existing situation, using Rehm tools HYKAS and GraPS under AutoCAD environment. The results of this study show that the size of the existing road side drains is inadequate to handle all the surface runoff. It is found that the existing situation of the drainage system is quite poor and need to be redesign or reconstruct immediately. The hydraulic load of almost all the conduit is beyond the limit assigned. The hydraulic design of the most of the drainage conduit is inadequate and re-design of the drain is essential based upon accurate flow estimation methods. This study concludes that the applicability of the current drainage system is quite poor and needs to make certain changes with their construction immediately in order to avoid any danger and adverse effect possessed by surface flooding over the road surface and other paved surfaces. The surface runoff is significantly increased compared to the situation before the construction of existing drainage system and therefore for the appropriate storm water management of the urban area of Nepal, it is critical to design the drainage system based on both hydrological and hydraulic analyses considering reliable data.

Technological and constructor solutions for the design of silage trenches using CAD

The features of the technological process of silage formation are described. A kinetic model of biochemical reactions in the preparation of silage juice was developed and investigated. The kinetic model was the ratio of the growth rate of the silage mass under the influence of a complex of factors on it: specific growth rate, concentration of microorganisms, the use of various additives. The models of emission processes occurring with the synthesis of methane and carbon dioxide are studied. A system of automated monitoring and control of the technological process of silage has been developed. The accounting and monitoring of greenhouse gases generated during silage decomposition is also an important environmental challenge. The design of silage trenches included calculations of the bearing capacity of the base and the stability of clay slopes. For the computer-aided design system, the AutoLISP software module of the AutoCAD environment was used. The developed computer-aided design system allows speeding up the construction of outline drawings with various geometric parameters of the silage trench.

Formation surfaces of Monge by the kinematic method in AutoCAD environment

Aims of research. Studying the possibility of forming Monge carved surfaces, defined by the method of their formation, creating an algorithm and program in the AutoLISP language to demonstrate the formation of surfaces in the AutoCAD environment in a dynamic mode. Methods. Monge carved surfaces are formed by a flat curve, located in the tangent plane to the fixed guide of the developable surface, when the plane and the curve roll along the guide surface without sliding. The described method of formation of these surfaces allows to perform their formation by the kinematic method in the AutoCAD environment using AutoLISP software. The article describes the construction of the Monge surfaces using cylindrical and conical surfaces as guides. A straight line and a sine wave are used as the forming lines. Results. An algorithm and a program in the AutoLISP language were created to form sets of compartments of several Monge surfaces and to visualize the formation of these surfaces in a dynamic mode by sequentially displaying the compartments on the monitor screen. The mini-film about formation of Monge surface by rolling a plane with a straight line along a circular cone is created. In the mini-film the drawings received by transformation of drawings of the AutoCAD environment are used.

Vizualizing of semi-regular polyhedrons in AutoCAD environment

The paper examines the automated formation by the kinematic method of the surfaces of Archimedes' semi-regular polyhedra of three forms: truncated tetrahedron, truncated octahedron and truncated icosahedron. To solve this problem, AutoCAD and the built-in programming language AutoLISP were used. Each of these five semi-regular polyhedra of Archimedes has faces of two kinds. In this regard, the surface of a separate polyhedron is considered to consist of two structural forms. Each structural shape is formed in the AutoCAD environment from the compartments of the surfaces of the faces of the polyhedron of the same type, and each compartment is assigned to a specific layer of the drawing. The formation of constructive forms is provided by user-defined functions developed in the functional programming language AutoLISP. User-defined functions not only form images of surfaces, but also perform all the necessary calculations. The electronic model of each polyhedron is formed by the union of its structural forms. A block is formed from it. The surface formation of each polyhedron performs user-defined functions that provide “freezing” of drawing layers intended for surface compartments, insertion of a block with an electronic model of the polyhedron, and sequential “defrosting” of drawing layers. When there is a “thawing" of the layers of the drawing, the process of forming a polyhedron is shown on the monitor screen. As a result of research software that includes userdefined functions for the formation of an electronic model of selected polyhedrons and visualization of the process of formation of their surfaces in a dynamic mode was created.

Визуализация правильных многогранников в процессе их образования

In this work the automated formation of surfaces correct to convex polyhedrons of Platon and two regular not convex star-shaped polyhedrons of Kepler-Poinsot by the kinematic method. Researches on realization of a goal were carried out in the environment of AutoCAD with use of the programs developed in the functional Autolisp programming language which is built in AutoCAD. The AutoLisp language and the AutoCAD environment are chosen for achievement of a goal as they allow showing bodies in the movement. The technique of formation of electronic models of the polyhedrons necessary for performance of visualization of polyhedrons is stated. The model is a set of compartments of a surface, issued in the form of the block. The user function in the AutoLisp language which identifier is team in the environment of AutoCAD is developed for each model. Each compartment was placed in the drawing layer which is taken away for it. When developing the user functions were taken into account to a possibility of the AutoCAD environment – the available teams for formation of surfaces. The user functions in the AutoLisp language for formation of the studied surfaces in the environment of AutoCAD are made by the defrosting method of the block containing surface compartments. In the course of "defrosting" of layers with compartments on the screen of the monitor process of formation of a surface is shown – drawings of compartments of a surface appear one by one. The last drawing is an image of a surface. The user functions in the AutoLisp language for formation of the studied surfaces in the environment of AutoCAD are made. The fragment of the program by training of one side of a tetrahedron is given Drawings of elements of surfaces of all regular polyhedrons of Platon and star-shaped polyhedrons of Kepler-Poinsot are provided in initial situation and in the course of stage-by-stage formation of these surfaces, the programs received in the environment of AutoCAD with use in the AutoLisp language. Drawings of elements of surfaces of all regular polyhedrons of Platon and star-shaped polyhedrons of Kepler-Poinsot are provided in initial situation and in the course of stage-by-stage formation of these surfaces, the programs received in the environment of AutoCAD with use in the AutoLisp language. The possibility of formation of surfaces of regular polyhedrons is shown by a kinematic method: the movement rectilinear forming on the directing lines as which edges of polyhedrons are used.

Automatic modelling of regular polyhedrons and visualizing their formation in AutoCad through the Autolisp language

Computer modeling of polyhedral surfaces is one of the most complex and interesting areas of architectural shaping. Computer-aided design systems, such as MathCad, Mathematika, AutoCad, etc., allow solving various problems on the formation of surfaces. The AutoCad system has significant advantages, because it has a built-in functional language AutoLisp, which has functions for mathematical calculations and for drawing different objects in 3D space. In this paper, a method of forming the surfaces of regular polyhedra in an AutoCAD environment through the use of programs in the language of Autolisp is considered.To demonstrate the method, a dodecahedron (Plato's body), a large dodecahedron and a small star dodecahedron (Kepler-Poinsot bodies) are selected.

Geometric and computer-aided spline hob modeling

The paper considers acquiring the spline hob geometric model. The objective of the research is the development of a mathematical model of spline hob for spline shaft machining. The structure of the spline hob is described taking into consideration the motion in parameters of the machine tool system of cutting edge positioning and orientation. Computer-aided study is performed with the use of CAD and on the basis of 3D modeling methods. Vector representation of cutting edge geometry is accepted as the principal method of spline hob mathematical model development. The paper defines the correlations described by parametric vector functions representing helical cutting edges designed for spline shaft machining with consideration for helical movement in two dimensions. An application for acquiring the 3D model of spline hob is developed on the basis of AutoLISP for AutoCAD environment. The application presents the opportunity for the use of the acquired model for milling process imitation. An example of evaluation, analytical representation and computer modeling of the proposed geometrical model is reviewed. In the mentioned example, a calculation of key spline hob parameters assuring the capability of hobbing a spline shaft of standard design is performed. The polygonal and solid spline hob 3D models are acquired by the use of imitational computer modeling.

DEVELOPMENT OF THE TYPICAL PASSPORT STRUCTURE OF INDUSTRIAL RAILWAYS

The article contains a brief description of the diversity of industrial enterprises that have railway tracks connected to the main Ukrainian railways on their balance sheet. The specifics of their work are considered depending on the nature and volume of cargo work, the length of the railway tracks, the availability of their own locomotives, technological transportation, etc. The regulatory and legal framework regulating the operation of industrial rail transport and its interaction with PJSC «Ukrzaliznytsya» is considered. A brief analysis of the documents regulating the technical condition of the railway infrastructure of access roads and their actual state has been completed.The need to develop a standard technical passport (TP) for access roads of an industrial enterprise and its main provisions and content is formalized. The need to amend the documents regulating the contents of the road development plans was noted with a view to more convenient visualization and display of the necessary elements.The presence of labor-intensive processes in the development of the TP drawings was noted. The software developed by the scientist of the department of stations and nodes of the DNURT is described, which makes it possible to speed up the development and scale design of longitudinal railroad tracks. This software product, based on the entered data on the plan and profile of the railway track based on geodetic survey data and on the processing of their results, automates the calculation, construction and registration of longitudinal profiles in the AutoCAD environment and allows to significantly reduce the overall duration of the entire range of design works and guarantee a high level of their quality.The analysis of the main problems related to the development and modification of the TP documentation is performed. In order to accelerate the development and editing of the TP documentation, specialized software has been developed in the form of an automated workplace that allows you to create a report and also to make changes and keep a log of changes.

Automatic modeling of the surfaces of the equal slope in AutoCad system through language AutoLisp

Graphical computer modeling is a real possibility of solving problems on the formation of surfaces by a kinematic method. It is due to the presence of automated design systems, such as MathCad, Mathematika, AutoCad, etc. The advantage of the AutoCad system is the presence of the built-in language of functional AutoLisp. Having a wide range of mathematical functions and functions for drawing graphic objects, the AutoLisp language allows you to write a program for drawing shells of any complexity, in a particular case - shells of the same ramp on the elliptical plane, the surface of the involute helicoid, and then transferring the results to the AutoCAD environment. Playing objects in slow motion makes it possible to compose mini-films about the formation of surfaces. The image of graphical constructions in three-dimensional space using the AutoCAD color palette enhances the expressiveness of the image of surfaces and their elements. The aim of the study is the possibility of modeling the surface of the equal slope ramp on an elliptical plane, carried out by its gradual drawing in a slow dynamic mode with the creation of a mini-film that allows the surface to be displayed on the monitor screen

Influence of tooth profile on the noncircular gear tooth contact

With noncircular gears, the continuous modification of the tooth meshing, in terms of variation of the tooth profiles and the line of action position and inclination, makes difficult the implementation of a general standard procedure for the analysis of the noncircular gears tooth contact. In this paper, the authors present a graphical approach that enables the tooth contact static pattern to be produced and evaluated in case of a noncircular gear with complex geometry of the pitch curve. The study is virtually developed, in AutoCAD environment, by animating and investigating the gear solid models in mesh. The tooth static contact analysis enables the path of contact area and distribution to be evaluated in correlation with the following variable initial data: gear pitch curve geometry, tooth profile geometry, as a consequence of different generating procedures, and the gear pressure angle. It was found out that the noncircular gear tooth contact could be improved by choosing different procedures for the tooth flank generation in concave and convex zones and by increasing the gear pressure angle.