Journal articles: 'Discrete tool surface'

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Chekalova, Elena A., and A. V. Zhuravlev. "Discrete Oxidation of a Hard Carbide Tool." Solid State Phenomena 316 (April 2021): 777–82. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.777.

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Comparative investigations of the effect of discrete surface hardening by standard ion-plasma technology and discrete oxidation technology on the structure and hardness of high-speed steels are carried out. It is shown that, after hardening in the ion-plasma installation on the surface and in the thickness of the layer, droplet-shaped defects, craters and bundles are formed. Metallographic studies showed that the hardened discrete oxidation layer after repeated hardening has a dense, uniform structure. It has been established that the discrete oxidation technology allows to increase the wear resistance of a complex-profile cutting tool 2 times more, compared to a tool hardened by standard ion-plasma technology after regrinding.

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Chen, Xu Bing, Chen Yu Shan, and You Lun Xiong. "Linear Octree Represented Tool Swept Volume Modeling on Complex Surface Machining." Applied Mechanics and Materials 190-191 (July 2012): 699–704. http://dx.doi.org/10.4028/www.scientific.net/amm.190-191.699.

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In this paper, a novel approach of linear octree is employed to represent discrete tools and build their swept volumes along machining trajectories. Firstly, a data structure of linear octree is defined as the base of geometrical transformations. The linear octree can be extended into leaf nodes in the deepest level for simplifying homogeneous transformations, and all leaf nodes in the deepest level can also be concentrated into a linear octree for saving storage capacity inversely. Secondly, tool trajectories are interpolated as short lines, and swept volumes between neighbor interpolation points are defined as the Minkowski sum of their cell sets at both locations. Thirdly, equations of the rotation matrix for local coordinate system, roll, pitch and yaw angles of tool orientations are established to define the global rotation motions. Finally, a case of discrete sphere tool and its swept volume modeling are studied to validate the proposed approach.

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Kitahara, Hiromu, Jun’ichi Kaneko, Masahiro Ajisaka, Takeyuki Abe, and Kenichiro Horio. "Accurate Tool Path Generation Method for Large-Scale Discrete Shapes." International Journal of Automation Technology 13, no. 2 (March 5, 2019): 279–88. http://dx.doi.org/10.20965/ijat.2019.p0279.

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Three-axis ball end mills are used for the finishing of metal molds of complicated curved surfaces. Typically, a tool path of this shape machining is derived from the geometric calculations of a tool used, and a product model that is a computer aided design (CAD)-based polyhedron approximating the shape. The polyhedron is more complicated to approximate a shape with more curved surfaces, as it is highly time consuming. To solve this problem, methods to accelerate geometric calculations using a computer graphics drawing processing mechanism were proposed. However, these methods cannot guard against errors arising from the approximation of an inverse offset shape using a set of polygons. In the present study, we propose a method to generate tool paths accurately based on calculating the crossing points of the tool axis and defining the offset surface as a set of polygons, cylindrical surfaces, and spherical surfaces. With this method, it is expected that the height of an area, which was divided by fine polygons in previous methods, can be derived accurately, and a tool path can be generated with high precision.

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Oancea, N., and V. G. Oancea. "Geometrical design of cutting tools with surfaces of revolution for helical surfaces." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 211, no. 7 (July 1, 1997): 559–66. http://dx.doi.org/10.1243/0954406971521944.

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Machining of helical surfaces of constant pitch with tools bounded by surfaces of revolution is accompanied by generation errors due to imperfections of the effective cutting edge, relative positioning errors or kinematics of the machine tool. Therefore, the development of algorithms for the geometrical modelling of helical surfaces could be very useful. In fact, it is possible to model geometrically the effective generated surface on the workpiece when the cutting edge is known at discrete points, for instance, by physical measurement. Based on the principle of minimal distance first proposed in a previous work of the first author, a numerical method is developed that provides a very simple, yet very accurate, means to resolve both the direct and the inverse problem in the machining of helical surfaces with milling cutters and end mills. Thus, the profile of the cutting tool can be determined even for surfaces on the workpiece of arbitrary shape known either analytically or at discrete points. More importantly, it can be established either in the design or the exploitation stage what the accepted errors on the tool are (due to sharpening or wear), such that the tolerances on the surface to be machined are still met.

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Морозов, Алексей, Aleksey Morozov, Владимир Гусев, and Vladimir Gusev. "Stressed state simulation of discrete abrasive disk cutting surface." Science intensive technologies in mechanical engineering 2, no. 10 (October 4, 2017): 18–23. http://dx.doi.org/10.12737/article_59d496ebddec57.65109772.

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Grinding disks with high frequency discretization of a cutting surface allow not only breaking a cutting process and de-creasing its thermal intensity, but decreasing a vibration level of a technological system which has a positive effect upon quality of a surface worked. But, for realization of intensive grinding modes these tools should possess a mechanical strength not only in the central hole, but that of a discrete cutting surface. In this connection in modern CAE-complex CosmosWorks a computer simulation of a stressed state of a cutting surface and a central hole of the grinding disk subjected to a high-frequency discretization is carried out. On the basis of the simulation results there is developed a durable tool allowing the fulfillment of discrete grinding in intensive modes.

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Fan, Li Cheng, Li Ning Sun, and Zhi Jiang Du. "A Tool-Path Interpolation Algorithm Based on Unfolding-Bending Parametric Curves." Key Engineering Materials 407-408 (February 2009): 220–24. http://dx.doi.org/10.4028/www.scientific.net/kem.407-408.220.

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To grind sculptured surface by swing motion, it’s needed to interpolate the discrete data nodes on the arc-driving surface. To ensure that all the sample points locate on the arc surface, a novel unfolding parameter curve is proposed. Firstly, all the discrete data are stretched onto a plane, inside which the cubic B-spline curves are interpolated. After that, some points are sampled from the spline curves and bended to the arc-driving surface according to the swing radius. To eliminate cutting vibration and chord error exceeds limitation; radial speed is tuned by controlling the chord error. The simulation results are given to prove the proposed algorithm.

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Dutta, Samik, Surjya K. Pal, and Ranjan Sen. "Progressive tool condition monitoring of end milling from machined surface images." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 232, no. 2 (April 7, 2016): 251–66. http://dx.doi.org/10.1177/0954405416640417.

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Indirect tool condition monitoring in end milling is inevitable to produce high-quality finished products due to the complexity of end-milling process. Among the various indirect tool condition monitoring techniques, monitoring based on image processing by analyzing the surface images of final product is gaining high importance due to its non-tactile and flexible nature. The advances in computing facilities, texture analysis techniques and learning machines make these techniques feasible for progressive tool flank wear monitoring. In this article, captured end-milled surface images are analyzed using gray level co-occurrence matrix–based and discrete wavelet transform–based texture analyses to extract features which have a good correlation with progressive tool flank wear. Contrast and second diagonal moment are extracted from gray level co-occurrence matrix and root mean square and energy are extracted from discrete wavelet decomposition of end-milled surface images as features. Finally, these four features are utilized to build support vector machine–based regression models for predicting progressive tool flank wear with 94.8% average correlation between predicted and measured tool flank wear values.

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Fussell, B. K., R. B. Jerard, and J. G. Hemmett. "Robust Feedrate Selection for 3-Axis NC Machining Using Discrete Models." Journal of Manufacturing Science and Engineering 123, no. 2 (June 1, 2000): 214–24. http://dx.doi.org/10.1115/1.1365398.

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This research effort is focused on improving the efficiency of CNC machining by automatic computer selection of feedrate for 3-axis sculptured surface machining. A feedrate process planner for complex sculptured end milling cuts is developed from mechanistic and geometric end milling models. The selection program uses tool deflection, surface finish, tool failure and machine power to set constraints on the cutting force and the feed-per-tooth for rough, semi-finish, and finish passes. A NC part program is processed one tool move at a time by the planner. For each tool move a geometric model calculates the cut geometry, and an inverse mechanistic model uses this information along with the constraint force to calculate a desired feedrate. The feedrate is written into the part program resulting in a file that contains a feedrate for each tool move. Experimental results for a sculptured surface show the accuracy of the algorithms in maintaining a desired force.

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Popa, Camelia, Virgil Gabriel Teodor, Nicuşor Baroiu, and Nicolae Oancea. "Side Mill Tool Profiling for Generation of Helical Surfaces Determined by Reverse Engineering." Applied Mechanics and Materials 657 (October 2014): 28–32. http://dx.doi.org/10.4028/www.scientific.net/amm.657.28.

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The compressor rotors usually are helical surfaces with constant pitch and are composed crossing profiles. Frequently, for repair operations occurs the reconstruction necessity for one or both of the worms, drive and driven, from the helical compressors gear. The helical composed surface of rotor flank is generated usually with side mill. The knowledge of worm shape can not be made from geometrical conditions. In these conditions it is necessary to determine the flank form by actual measuring the crossing profiles of these parts. So, the theoretical helical surface of the worm is being substituted by an assembly of helical lines which together with crossing profiles forms points cloud resulted from measuring leads to a polyhedral expression of the flank rotor. Numerically, this surface type is expressed by a coordinate array which shows its discrete image. The profiling of cutting tool bounded by a revolution surface reciprocally enveloping with the substitutive surface of the helical one represents a special problem. In this paper is proposed an algorithm for polyhedral expression of the helical surface previously determined by reverse engineering methods and an algorithm for the determination of the specific enveloping condition at contact with a discrete surface.It is presented an example for a compressor rotor measured on a 3D measuring machine, the algorithm for the transformation of the gathered points cloud in a surface with polyhedral expression. Given these conditions there were determined the enveloping condition and the axial section of the side mill.

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He, Wei, Min Ren, and Ying Qi Tan. "Realization of NURBS Surface CNC Machining Simulation in Matlab." Advanced Materials Research 461 (February 2012): 381–83. http://dx.doi.org/10.4028/www.scientific.net/amr.461.381.

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This paper presents a method of realization of NURBS surface CNC Machining simulation in matlab, including NURBS surface production, tool path generation, discrete surface and simulation model construction and CNC machining simulation realization.

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Cao, Shu Kun, Li Song, Kai Feng Song, Jie Lv, and Xiu Sheng Chen. "Free-Form Surface Five-Axis Machining Tool Path and Tool Posture Simultaneous Multi-Objective Optimization Theory Research." Key Engineering Materials 467-469 (February 2011): 900–905. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.900.

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In view of all sorts of questions existing in CNC machining, such as machining vibration, so proposed a new simultaneous multi-objective optimization algorithm on free-form surface five-axis machining tool path and tool posture based on constant scallop height. In the algorithm, we first complete the surface fitting on the base of feature points obtained. Secondly calculate principal curvatures of the surface, select tools, and at the same time generate tool axis vector in the current cutter-contact point tool axis. Once again get the maximum spacing and surface curvature in accordance with the tool effective cutting radius, discrete into cutter-contact point, and calculate the cutting depth to adjust the machine feed rate. And finally connect adjacent curve path using the diagonal to achieve a continuous cutting scallop height tool path. This algorithm can achieve the goals such as the same precision, improving processing efficiency, reducing the number of tool cutting in and out, reducing cutting vibration and tool wear and so on. That is the algorithm can achieve simultaneous multi-objective optimization of the free-form surface NC machining finally.

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Gupta, Suprakash, and J. Bhattacharya. "Discrete Markov chains - An analytical tool for productivity analysis of surface mining systems." International Journal of Surface Mining, Reclamation and Environment 13, no. 3 (January 1999): 111–16. http://dx.doi.org/10.1080/09208119908944226.

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Морозов, Алексей, Aleksey Morozov, Владимир Гусев, and Vladimir Gusev. "Temperature simulation of blank ground with face solid and segment disks in CAE-Solid Works complex." Science intensive technologies in mechanical engineering 2, no. 11 (October 25, 2017): 23–29. http://dx.doi.org/10.12737/article_59f074a6a83b54.31913450.

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Flat face grinding is characterized with large areas of a cutting surface contact with a blank under machining which re-sults in intensive heat generations in a cutting area which is able to cause a thermal damage of the surface layer. Thereupon there is developed a designed heat model of a blank, the initial conditions are defined, and there is created a solid-state model of an abrasive segment with a trapezoidal face cutting surface and a temperature simulation of the blank ground with a solid and discrete face tool is carried out in a modern CAE- Solid Works complex. The result of modeling have shown that the application of the discrete face grinding tool equipped with abrasive segments allows decreasing a temperature of the surface machined by 26-30% as compared to a face grinding tool with a solid cutting surface, which decreases considerably the likelihood of defects appearance in a ground surface layer of a part.

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Goupil, Antoine, Ivan Iordanoff, Jean Luc Charles, and André Rinchet. "Modelling of Polishing Tools for High Spatial Frequency Defect Correction on Aspherical Surfaces." Key Engineering Materials 554-557 (June 2013): 1232–41. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.1232.

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Nowadays, precision Computer Controlled Optical Surfacing (CCOS) and processes like Ion Beam Finishing (IBF) or Magneto-Rheological Finishing (MRF) allow manufacturing of fused silica optics with nanometer precision. However, High spatial frequency defects remain on the optics and need to be previously smoothed. Full aperture semi-flexible polishing tools can be used, as they can guarantee uniform pressure on low frequency patterns to preserve the pre-formed aspherical shape while maintaining a high pressure differential on high frequency defects, thus smoothing them. That behavior can be obtained with tools that combine a continuous flexible layer for low frequency compliance and a fractionate viscoelastic polishing layer for high frequency defect polishing. The main goals of this study are predicting smoothing efficiency and form control of different tools, and then determining the best tool to achieve a good balance between them. To do this, a multiscale model is developed. First, at the whole tool scale, for a given aspherical shape, the largest misfit between tools and surfaces is mathematically determined, depending on machining parameters. Then a finite-element parametric study is performed and yields for the flexible layer the best mechanical properties and thickness as well as the optimal applied force to achieve pressure homogeneity at the global aspherical shape level. Second, at the viscoelastic polishing layer level, the Discrete Element Method (DEM) is used to investigate the tool – workpiece interface. A model based on the viscoelastic cohesive beam method is developed, thus allowing taking into account the polishing layer’s dynamic response depending on the excitation frequency. The optical surface is also modeled by interpenetrated discrete elements, paving the way for a full-DEM model of the polishing layer – workpiece interface. Smoothing simulations are separated in two steps : the first one is the initial pressure application, leading to an initial state of full tool – surface contact with an homogeneous pressure. Then the tool is moved over the surface and the dynamic pressure is calculated depending on defect and polishing layer properties as well as tool kinematics. By analyzing the pressure differential on defects it becomes possible to calculate the smoothing efficiency of a given polishing layer and therefore optimize its properties depending on the defects that need to be smoothed.

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Zhang, Liang, J. Li, and B. C. Lou. "Tool Path Planning for Five-Axis NC Machining of Implant Shaping Mold for Cranioplasty." Materials Science Forum 697-698 (September 2011): 292–96. http://dx.doi.org/10.4028/www.scientific.net/msf.697-698.292.

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The necessity for skull patch surface for cranioplasty was introduced and it was divided according to maximum normal curvature in the discrete points after skull patch surface dispersed. Then the tool axis vector was determined by the lead angle of the tool, corresponding to generating the tool path in each area; At last, the implant shaping mold for cranioplasty was produced by five-axis NC machine.

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Cao, Shu Kun, Li Song, Ke Dong, Kai Feng Song, and Zhi Ming Sui. "Research on Path Optimization Technology for Free-Form Surface Five-Axis NC Machining." Advanced Materials Research 443-444 (January 2012): 202–8. http://dx.doi.org/10.4028/www.scientific.net/amr.443-444.202.

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In view of all sorts of questions existing in CNC machining, such as machining vibration, so proposed a new method of free-form surface NC machining path optimization based on constant scallop height. This method first discrete surface boundary into the knife touch point based on the maximum tolerance, then in accordance with the maximum allowable scallop height generates circular trajectory with the same scallop, and finally connects adjacent curve path using the diagonal to achieve a continuous cutting scallop height tool path. This method can reduce the number of tools cut in and out parts, reduce the processing vibration and tool wear, and the surface processed has the same precision. This method has simple calculation, suitable for free-form surface of CNC highspeed and precision machining.

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Liu, Wei, Lai Shui Zhou, and Lu Ling An. "3-Axis NC Rough Tool-Path Generation from Discrete Data Points of Reliefs." Applied Mechanics and Materials 43 (December 2010): 484–87. http://dx.doi.org/10.4028/www.scientific.net/amm.43.484.

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This paper presents an algorithm through which 3-axis NC rough tool-paths can be directly generated from discrete data points. Based on Inverse Tool Offset (ITO) method, the algorithm generates direction-parallel (DP) tool paths for relief point clouds. The algorithm includes four steps: dividing data points into 3D cell grids; constructing inverse tool model and calculating the grids intersecting the surface of inverse tool; obtaining the grids containing cutter location points; calculating tool paths. The experiment results indicate that the algorithm of the rough tool paths is efficient.

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Han, Shi Guo, Jun Zhao, and Xiao Feng Zhang. "Surface Topography and Roughness Simulations for 5-Axis Ball-End Milling." Advanced Materials Research 69-70 (May 2009): 471–75. http://dx.doi.org/10.4028/www.scientific.net/amr.69-70.471.

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In five-axis high speed milling of freeform surface with ball-end cutters, unwanted machining results are usually introduced by some error effects. Hence precise modeling and simulation of milled sculptured surfaces topography and roughness is the key to obtain optimal process parameters, satisfactory surface quality and high machining efficiency. In this paper, a predictive model for sculptured surface topography and roughness of ball-end milling is developed. Firstly, a mathematical model including both the relative motion of the cutter-workpiece couple and some influential factors on machined surface quality such as the tool runout, tool deflection and tool wear is proposed, and subsequently the analytical form of the tool swept envelope is derived by means of homogeneous coordinate transformation. Then the minimal z-values of the corresponding points lied in discrete cutting edges model and Z-map workpiece model are used to update the workpiece surface topography and to calculate 3D surface roughness. Finally, the simulation algorithm is realized with Matlab software. A series of machining tests on 3Cr2MoNi steel are conducted to validate the model, and the machined surface topography is found in good accordance with the simulation result.

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Dutta, Samik, Surjya K. Pal, and Ranjan Sen. "Progressive tool flank wear monitoring by applying discrete wavelet transform on turned surface images." Measurement 77 (January 2016): 388–401. http://dx.doi.org/10.1016/j.measurement.2015.09.028.

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Cao, Shu Kun, Yong Hong Deng, Kun Zhang, Shi Ping Liu, and Wen Jing Meng. "Free Surface NC Machining Tool Path Optimization Algorithm Based on the Iso-Scallop Method." Applied Mechanics and Materials 799-800 (October 2015): 1193–96. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.1193.

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In order to solve the problem of free surface processing of tool redundancy,the tool lack problem, and the demerit of low machining efficiency, etc., based on the iso-scallop method, based on the iso-scallop method, we put forward a kind of free surface NC machining tool path optimization algorithm,make the surface boundary discrete point set, which is generated by point set ring machining path, diagonal connection and then use the path of the adjacent curve, forming cutting tool machining line.finally, the calculation of step size and line spacing in machining path based on the iso-scallop method and the process of feeding direction is optimized. Proved by the simulation process, the algorithm is feasible and can effectively avoid tool redundancy and tool lack problems,concesquently, processing efficiency improved significantly.

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Mann, James B., Yang Guo, Christopher Saldana, Ho Yeung, W. Dale Compton, and Srinivasan Chandrasekar. "Modulation-Assisted Machining: A New Paradigm in Material Removal Processes." Advanced Materials Research 223 (April 2011): 514–22. http://dx.doi.org/10.4028/www.scientific.net/amr.223.514.

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Modulation Assisted Machining (MAM), based on controlled superimposition of low-frequency modulation to conventional machining, effects discrete chip formation and disrupts the severe contact condition at the tool-chip interface. The underlying theory of discrete chip formation and its implications are briefly described and illustrated. Benefits such as improved chip management and lubrication, reduction of tool wear, enhanced material removal, particulate manufacturing and surface texturing are highlighted using case studies. MAM represents a new paradigm for machining in that it deliberately employs ‘good vibrations’ to enhance machining performance and capability.

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Okhlupin, D. N., A. V. Korolev, and I. V. Sinev. "New material for anti-wear corrosion-resistant coating of agro industrial complex machinery parts." E3S Web of Conferences 222 (2020): 01002. http://dx.doi.org/10.1051/e3sconf/202022201002.

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The article presents the results of an experimental study of the corrosion resistance of the ta-C double coating of parts by PVD method with intermediate and final surface polishing with a discrete tool. The influence of regime factors on the results of polishing the ta-C coating with a discrete tool is shown, and optimal processing modes are proposed. Tests of samples in a salt bath showed that the double ta-C coating by PVD method with intermediate and final polishing ensures the absence of corrosion and coating peeling

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Гусев, Владимир, Vladimir Gusev, Алексей Морозов, and Aleksey Morozov. "Discretization technology of abrasive disc operating surfaces with laser and hydro-abrasive jet." Science intensive technologies in mechanical engineering 2, no. 9 (September 5, 2017): 21–27. http://dx.doi.org/10.12737/article_59ae90c6572822.07490267.

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The well-known discrete abrasive discs are characterized by a high vibration level of the technological system that causes the geometrical characteristics degradation of surfaces ground, life and technological equipment decrease and tool quick wear. New methods of the high-frequency discretization of a cutting surface with the use of a laser beam and a hydro-abrasive jet and also designs of grinding tools decreasing a vibration level of the technological system are developed. The processes of the high-frequency discretization of grinding discs are improved experimentally: the path of a high-concentrated energy flow motion is substantiated, the modes of hole cutting out in abrasive of a tool and a field of the application of a laser beam and a high-pressure hydro-abrasive jet are defined.

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Wei, Yi, Peng Zhai, Xiaoyi Chen, and Lei He. "Study on Design and Diamond Turning of Optical Freeform Surface for Progressive Addition Lenses." Mathematical Problems in Engineering 2020 (February 22, 2020): 1–9. http://dx.doi.org/10.1155/2020/2850606.

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Optical freeform surface components have attracted much attention due to their high degree of design freedom and small size. However, the design and processing difficulty of such components limit its wide application in optics industry. In recent years, diamond turning has been considered an efficient method for processing optical freeform surfaces, but the research on tool path generation of this processing method is not systematic. Progressive addition lens (PAL) is a typical optical freeform surface and is widely used to correct people’s vision problems. Firstly, this paper introduces a method of designing PAL. Then, an optimized tool path generation method for diamond turning of the optical freeform surface is proposed, the equal angle method is used to select the discrete points, and a tool nose radius compensation method suitable for both slow slide servo (SSS) and fast tool servo (FTS) is adopted. Finally, the turning experiment is carried out with a single point diamond lathe, and a PAL surface with a roughness of 0.087 μm was obtained. The power and astigmatism distributions were measured using a Rotlex freeform verifier to verify the rationality of the optical design.

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Korngold, J. C., and G. A. Gabriele. "Multidisciplinary Analysis and Optimization of Discrete Problems Using Response Surface Methods." Journal of Mechanical Design 119, no. 4 (December 1, 1997): 427–33. http://dx.doi.org/10.1115/1.2826386.

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The objective of this paper is to present a new algorithm to efficiently optimize multidisciplinary, coupled nonhierarchic systems with discrete variables. The algorithm decomposes the system into contributing disciplines, and uses designed experiments within the disciplines to build local response surface approximations to the discipline analysis. First and second order Global Sensitivity Equations are formulated and approximated by experimental data to build approximations to the global design space. The global approximation is optimized using branch and bound or simulated annealing. Convergence is rapid for systems with near quadratic behavior. The algorithm is demonstrated on a unique multidisciplinary learning tool, the Design and Manufacturing Learning Environment. This environment provides multimedia simulation for product life cycle disciplines, including design, manufacturing, marketing, and sales.

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Haghpassand, K., and J. H. Oliver. "Computational Geometry for Optimal Workpiece Orientation." Journal of Mechanical Design 117, no. 2A (June 1, 1995): 329–35. http://dx.doi.org/10.1115/1.2826143.

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Workpiece orientation is formulated as an optimal design problem based on a discrete approximation of design surface geometry, the kinematic capabilities of the process machine tool, and processing cost. The primary process application addressed is three-and four-axis numerically controlled (NC) milling, although the techniques presented may be applied to machines with more general articulation. Recent developments in applied spherical geometry are employed to formulate a constrained problem, and furthermore, a nonlinear optimization problem. For three-axis milling applications, a weight is assigned to each surface normal of the discrete model corresponding to the actual area it represents. Workpiece/machine orientation is optimized such that the angle between the weighted normals and the milling tool axis is minimized. This formulation is augmented, for four-axis milling, to incorporate limitations of the rotational degree of freedom, into the optimization formulation. The influence of tool geometry is also discussed and incorporated within constrained orientation algorithm.

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Bharti, Bhuvnesh, David Rutkowski, Koohee Han, Aakash Umesh Kumar, Carol K. Hall, and Orlin D. Velev. "Capillary Bridging as a Tool for Assembling Discrete Clusters of Patchy Particles." Journal of the American Chemical Society 138, no. 45 (November 8, 2016): 14948–53. http://dx.doi.org/10.1021/jacs.6b08017.

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Qiu, Ying, Mei Lin Gu, Feng Guang Zhang, and Zhi Wei. "Study on Machining Mechanism of Glass Using Discrete Element Method." Applied Mechanics and Materials 577 (July 2014): 108–11. http://dx.doi.org/10.4028/www.scientific.net/amm.577.108.

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The discrete element method (DEM) is applied to glass micromachining in this study. By three standard tests the discrete element model is established to match the main mechanical properties of glass. Then, indentating, cutting, micro milling process are simulated. Results show that the vertical damage depth is prevented from reaching the final machined surface in cutting process. Tool rake angle is the most remarkable factor influencing on the chip deformation and cutting force. The final machined surface is determined by the minimum cutting thickness per edge. Different cutting thickness, cutter shape and spindle speed largely effect on the mechanism of glass.

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Akgandüller, Ömer, and Sibel Paşalı Atmaca. "Discrete Normal Vector Field Approximation via Time Scale Calculus." Applied Mathematics and Nonlinear Sciences 5, no. 1 (March 31, 2020): 349–60. http://dx.doi.org/10.2478/amns.2020.1.00033.

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AbstractThe theory of time scales calculus have long been a subject to many researchers from different disciplines. Beside the unification and the extension aspects of the theory, it emerge as a powerful tool for mimetic discretization process. In this study, we present a framework to find normal vector fields of discrete point sets in ℝ3 by using symmetric differential on time scales. A surface parameterized by the tensor product of two time scales can be analogously expressed as the vertex set of non-regular rectangular grids. If the time scales are dense, then the discrete grid structure vanishes. If the time scales are isolated, then the further geometric analysis can be executed by using symmetric dynamic differential. Moreover, we present an algorithmic procedure to determine the symmetric dynamic differential structure on the neighborhood of points in surfaces. Our results indicate that the method we present has good approximation to unit normal vector fields of parameterized surfaces rather than the Delaunay triangulation for some points.

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Tomizuka, M., M. S. Chen, S. Renn, and T. C. Tsao. "Tool Positioning for Noncircular Cutting With Lathe." Journal of Dynamic Systems, Measurement, and Control 109, no. 2 (June 1, 1987): 176–79. http://dx.doi.org/10.1115/1.3143836.

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This paper presents the design and implementation of a digital controller for a lathe to machine workpieces with noncircular cross sections. Noncircular cutting is accomplished by controlling the radial tool position in the direction normal to the surface of workpiece. A discrete time model for the tool carriage in the radial direction is obtained by a least squares method applied to input and output data. The model is used for designing digital feedback and feedforward controllers. The zero phase error tracking control algorithm is applied as a feedforward control law for positioning of the tool along desired time varying signals. The effectiveness of the proposed controller is demonstrated by experiment and simulation.

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Luis-Delgado, José Darío, Basil Mohammed Al-Hadithi, and Agustín Jiménez. "A Novel Method for the Design of Switching Surfaces for Discretized MIMO Nonlinear Systems." International Journal of Applied Mathematics and Computer Science 27, no. 1 (March 28, 2017): 5–17. http://dx.doi.org/10.1515/amcs-2017-0001.

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Abstract Designing variable structure control with sliding mode (VSC-SM) control schemes needs a switching function or a sliding surface which guarantees the global stability of the closed-loop system. Despite the fact that a wide range of design approaches has been proposed for solving this mathematical problem, the number of proposed methodologies for nonlinear systems is not very extensive, especially for discrete time nonlinear MIMO systems, and most of them require some coordinate system transformation. Therefore, it is not an easy task to find a design scheme that can be applied to discrete time nonlinear MIMO systems. The proposed methodology introduces a mathematical tool: a switching surface equation for a class of MIMO nonlinear systems through an explicit equation without any coordinate transformation. This equation makes use of an implicit linearizing process via the Taylor expansion that allows the use of linear procedures for the design of switching surfaces and the forward Euler method to obtain a discrete time dynamics representation. An illustrative example is included to show the advantages of the proposed design methodology.

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Oliver, J. H. "Efficient Intersection of Surface Normals With Milling Tool Swept Volumes for Discrete Three-Axis NC Verification." Journal of Mechanical Design 114, no. 2 (June 1, 1992): 283–87. http://dx.doi.org/10.1115/1.2916944.

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An efficient algorithm is presented for intersecting vectors with swept solids which represent three-axis numerically controlled (NC) milling tool motions. The intersection calculation proceeds in hierarchical steps through a series of progressively more exact definitions of the shape of the tool swept volume. At each step, results of intermediate calculations are used to determine whether intersection with an exact representation of the solid is possible and, if so, where and how the swept volume model must be refined for the next step. This structure ensures that superfluous intersection calculations are minimized. This intersection technique has been successfully implemented as part of an algorithm for automatic verification of three-axis NC milling programs, and may also be useful for applications in robotics and factory automation.

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Han, Quanquan, and Riliang Liu. "Theoretical modeling and error analysis for CNC whirling of the helical surfaces of custom screws using common inserts." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 11 (December 2, 2013): 1948–57. http://dx.doi.org/10.1177/0954406213513573.

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With the wide use of complex helical surfaces in screw components, it becomes more and more urgent to investigate efficient ways for the design and manufacture of components of this kind. This study establishes the mathematical model of helical surface based on discrete points on its axial section profile using cubic spline curve fitting method, and presents a theoretical approach to calculate the tool path for the whirling process which aims to produce the helical surface through enwrapping movements of standard cutters inserted in the tool ring. The approach is implemented in MATLAB environment focusing on the calculation of the cutter location points. After that, the theoretical machining error is analyzed focusing on the scallop height, which can be divided into axial and cross-sectional errors. Finally, a case study is provided, together with numerical simulation demonstrating the validity of the proposed approach.

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Sun, Dian Zhu, Xin Cai Kang, Yan Rui Li, and Yong Wei Sun. "An Algorithm for Geometric Modeling and Intersection in NC Milling Simulation Based on Triangular Mesh Model." Applied Mechanics and Materials 48-49 (February 2011): 541–46. http://dx.doi.org/10.4028/www.scientific.net/amm.48-49.541.

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To achieve the accurate and efficient NC milling simulation based on the discrete triangular mesh model, we proposed an algorithm for geometric modeling and intersection. We construct the R*-tree index for upper-surface nodes of mesh model, based on which the nodes within cutting region can be obtained. We compute tool path segments within cutting projection region of node, and calculate the minimum adjustment height of node according to tool path segments within cutting projection region and then change the z-value of node. Thus, we complete the intersection calculation in simulation process. It has been proved by examples that the algorithm for geometric modeling and intersection in NC milling simulation has strong adaptation to tool path segment type and that it can accurately and efficiently reflect the effect of NC simulation process based on the discrete triangular mesh model of rough.

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Huang, Yao, Yun Huang, and Rong Kai Cheng. "Research on Cutter-Contact Point Data Calculation of Robotic Abrasive Belt Polishing for Gun-Receiver Surface." Advanced Materials Research 797 (September 2013): 61–66. http://dx.doi.org/10.4028/www.scientific.net/amr.797.61.

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Coordinate transformation in robotic abrasive belt polishing system and the calculation method of robot working point by cutter-contact point data are analyzed in this paper. Calculation process of cutter-contact point data is given in this paper, the process mainly includes acquisition and discrete of polishing tool path and the associated vector calculation. Subsequently, detail of the process such as tool path pattern, row spacing, step distance and best contact conditions are analyzed and calculated. Finally, in visual studio environment, the cutter-contact point data of gun-receiver surface is generated by calling UG / Open API function.

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Bratan, Sergey, Stanislav Roshchupkin, and Anastasia Chasovitina. "The Correlation of Movements in the Technological System during Grinding Precise Holes." Materials Science Forum 1037 (July 6, 2021): 384–89. http://dx.doi.org/10.4028/www.scientific.net/msf.1037.384.

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The article presents the results of the study of the quality parameters of the precise hole, depending on the size, spatial location and condition of the contacting surfaces, the parameters of the state of the contact zone, during finishing grinding. The correlation between the processing modes and the current parameters of the contact zone during internal grinding is established. Dependencies describe the flow cross-feed for the i-th turn increment of the depth of micro-cutting, compensation of radial material removal previous turn, deterioration of the wheel, the increment of the elastic and thermal strains. At the same time, the depth of micro-cutting and the increment of elastic and temperature deformations affect the values of the radial wear of the tool and the radial removal of the material. The equation of displacement balance is developed for discrete processes of hole processing with abrasive tools, during which the analyzed surface area comes into contact with the abrasive tool periodically.

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Gao, Hui, Da Wei Zhang, Bin Liu, and Long Chen Duan. "Surface Lunar Soil Excavation Simulation Based on Three-Dimensional Discrete Element Method." Applied Mechanics and Materials 376 (August 2013): 366–70. http://dx.doi.org/10.4028/www.scientific.net/amm.376.366.

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One of the important objectives of lunar exploration is to obtain the lunar soil samples. However, the sampling process is very different from that on the Earth due to special characteristics of the lunar soil and surface environment. In order to ensure that the lunar exploration and sampling are successful, large numbers of ground experiments and computer simulations must be taken. In this paper, the surface lunar soil excavation simulation is investigated by three-dimensional discrete element method (DEM). It is implemented based on the open source LIGGGHTS, which takes the lunar soil as spherical particles. The interaction between the excavation tool and lunar soil is demonstrated. The excavation force and torque have also been calculated in real time. Moreover, the comparison of the excavation in different environments between the Earth and Moon corresponding to their different gravity accelerations was done. This paper shows that three-dimensional discrete element method can be used for the surface lunar soil excavation simulation and can provide important reference results for actual operations.

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Yong, Jiahao, Junfeng Liu, Chaoliang Guan, Yifan Dai, Fei Li, and Zhanbin Fan. "Fabrication and evaluation of complicated microstructures on cylindrical surface." PLOS ONE 15, no. 12 (December 15, 2020): e0242918. http://dx.doi.org/10.1371/journal.pone.0242918.

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Various items of roll molds are popularly used to fabricate different kinds of optical films for optoelectronic information and other new and high-tech fields, while the fabrication and evaluation of optical microstructures on a cylindrical roller surface is more difficult than ecumenically manufactured products. In this study, the machinability of microstructures on the roll based on a fast tool servo (FTS) system is investigated. First, the flexible hinge holder for a FTS is designed and its structural parameters are optimized with finite-element analysis and fatigue reliability theory. The tool radius compensation algorithm for complicated microstructures is then deduced based on the surface fitting and bilinear interpolation algorithm of discrete data. Meanwhile, the evaluation index and method are proposed by the medium section method. Finally, a machining test of aspheric arrays on a cylindrical aluminum surface is carried out, and the high quality of the microstructure indicates that the proposed method is able to be used to fabricate optical microstructures.

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Liu, Xianbing, Masakazu Soshi, Abhijit Sahasrabudhe, Kazuo Yamazaki, and Masahiko Mori. "A Geometrical Simulation System of Ball End Finish Milling Process and Its Application for the Prediction of Surface Micro Features." Journal of Manufacturing Science and Engineering 128, no. 1 (January 28, 2005): 74–85. http://dx.doi.org/10.1115/1.2039098.

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Finish milling with a ball end mill is a key process in manufacturing high-precision and complex workpieces, such as dies and molds. Because of the complexity of the milling process, it is difficult to evaluate the microcharacteristics of machined surfaces real time, which necessitates the simulation of the process. In this area, the existing related simulation researches mainly focus on scallop height evaluation, but few have presented a whole picture of the microcharacteristics of milled surfaces. This paper develops a comprehensive simulation system based on a Z-map model for predicting surface topographic features and roughness formed in the finish milling process and studies the effect of machining parameters. The adoption of the discretization concept of the tool’s cutting motion makes it possible to dynamically track the cutting tool-workpiece interaction with the tool movement and to describe the cutting edges-workpiece discrete cutting interaction more realistically and, therefore, the microcharacteristics of the machined surfaces more accurately. Also, the effects of the cutting tool run-out and wear are incorporated into the developed model through modifying the tool center motion and the cutting-edge shape, respectively. As a fundamental study, the tool-swept envelope has been simulated. The developed simulation system is applied to thoroughly study the surface features formed by the 2.5-axis finish milling process. The application for general three-axis machining is discussed. Additionally, this paper studies the effect of the tool inclination, which is the most common characteristic in 3+2- or five-axis milling processes, on the machined surface features. Experiments are carried out to study the milling process and to verify the simulation results. The difference between the simulated and experimental results is discussed, and the reason behind the difference is explored.

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Zarekarizi, Mahkameh, K. Joel Roop-Eckart, Sanjib Sharma, and Klaus Keller. "The FLOod Probability Interpolation Tool (FLOPIT): A Simple Tool to Improve Spatial Flood Probability Quantification and Communication." Water 13, no. 5 (March 1, 2021): 666. http://dx.doi.org/10.3390/w13050666.

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Understanding flood probabilities is essential to making sound decisions about flood-risk management. Many people rely on flood probability maps to inform decisions about purchasing flood insurance, buying or selling real-estate, flood-proofing a house, or managing floodplain development. Current flood probability maps typically use flood zones (for example the 1 in 100 or 1 in 500-year flood zones) to communicate flooding probabilities. However, this choice of communication format can miss important details and lead to biased risk assessments. Here we develop, test, and demonstrate the FLOod Probability Interpolation Tool (FLOPIT). FLOPIT interpolates flood probabilities between water surface elevation to produce continuous flood-probability maps. FLOPIT uses water surface elevation inundation maps for at least two return periods and creates Annual Exceedance Probability (AEP) as well as inundation maps for new return levels. Potential advantages of FLOPIT include being open-source, relatively easy to implement, capable of creating inundation maps from agencies other than FEMA, and applicable to locations where FEMA published flood inundation maps but not flood probability. Using publicly available data from the Federal Emergency Management Agency (FEMA) flood risk databases as well as state and national datasets, we produce continuous flood-probability maps at three example locations in the United States: Houston (TX), Muncy (PA), and Selinsgrove (PA). We find that the discrete flood zones generally communicate substantially lower flood probabilities than the continuous estimates.

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Socrate, Simona, and Mary C. Boyce. "A Finite Element Based Die Design Algorithm for Sheet-Metal Forming on Reconfigurable Tools." Journal of Engineering Materials and Technology 123, no. 4 (July 24, 2000): 489–95. http://dx.doi.org/10.1115/1.1395576.

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Tooling cost is a major contributor to the total cost of small-lot production of sheet metal components. Within the framework of an academic/industrial/government partnership devoted to the development of a reconfigurable tool for stretch forming, we have implemented a Finite Element-based procedure to determine optimal die shape. In the reconfigurable forming tool (Hardt, D. E. et al., 1993, “A CAD Driven Flexible Forming System for Three-Dimensional Sheet Metal Parts,” Sheet Metal and Stamping Symp., Int. Congress and Exp., Detroit, MI, SAE Technical Paper Series 930282, pp. 69–76.), the die surface is created by the ends of an array of square pins, which can be individually repositioned by computer driven servo-mechanisms. An interpolating polymer layer is interposed between the part and the die surface to attain a smooth pressure distribution. The objective of the die design algorithm is to determine optimal positions for the pin array, which will result in the desired part shape. The proposed “spring-forward” method was originally developed for matched-die forming (Karafillis, A. P., and Boyce, M. C., 1992, “Tooling Design in Sheet Metal Forming using Springback Calculations,” Int. J. Mech. Sci., Vol. 34, pp. 113–131.; Karafillis, A. P., and Boyce, M. C., 1996, “Tooling And Binder Design for Sheet Metal Forming Processes Compensating Springback Error,” Int. J. Tools Manufac., Vol. 36, pp. 503–526.) and it is here extended and adapted to the reconfigurable tool geometry and stretch forming loading conditions. An essential prerequisite to the implementation of the die design procedure is the availability of an accurate FE model of the entire forming operation. The particular nature of the discrete die and issues related to the behavior of the interpolating layer introduce additional challenges. We have first simulated the process using a model that reproduces, as closely as possible, the actual geometry of the discrete tool. In order to optimize the delicate balance between model accuracy and computational requirements, we have then used the information gathered from the detailed analyses to develop an equivalent die model. An automated algorithm to construct the equivalent die model based on the discrete tool geometry (pin-positions) is integrated with the spring-forward method, to generate an iterative die design procedure that can be easily interfaced with the reconfiguring tool. The success of the proposed procedure in selecting an optimal die configuration is confirmed by comparison with experimental results.

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Ju, Gang Gang, Qing Hua Song, and Zhan Qiang Liu. "Prediction of Cutter-Workpiece Engagement for Five-Axis Ball-End Milling." Materials Science Forum 800-801 (July 2014): 254–58. http://dx.doi.org/10.4028/www.scientific.net/msf.800-801.254.

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Five-axis ball-end milling technology is widely used in many industries such as aerospace, automotive and die-mold for complex surface machining. Despite recent advances in machining technology, productivity in five-axis ball-end milling is still limited due to the high cutting forces and stability. Moreover, cutting forces in machining is determined by extracting the cutter workpiece engagement (CWE) from the in-process workpiece. A discrete boundary representation method is developed. Cutter is firstly divided into disk elements along the tool axis. And in each disk element, boundary representation based exact Boolean method is introduced for extracting complex cutter-workpiece engagements at every cutter location due to its efficiency and speed over other discrete methods. Developed engagement model is proved to calculate complex engagement regions between tool and workpiece efficiently and accurately.

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Chen, Bing, Kai Liu, and Qiu Shi Gao. "A Method to Calculate Tool Accessible Domain Based on the Point Model for the Multi-Axis CNC Machining." Advanced Materials Research 591-593 (November 2012): 781–84. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.781.

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This paper puts forward a kind of method which can calculate tool accessible domain for tool axis optimization in the complex curved surface multi-axis machining. At first , the point model has been construced on the base of constrained surface.The second, based on any possible direction of tool axis vector of a given cutting contact point, the distance between a point and a line is used to decide whether occurs collision and interfence. The third, two angles related with cutter-axes vector is definied. The regulation of tool accessible domain can be implemented by getting the boundary of the discrete points in the coordinate planes. Finally, a tool has been developed to calculate tool accessible domain, and an example is given to verify the effectiveness of the method.

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Joni, Hasan H., Imzahim A. Alwan, and Ghazwan Naji. "Utilizing Artificial Intelligence to Collect Pavement Surface Condition Data." Engineering and Technology Journal 38, no. 1A (February 8, 2020): 74–82. http://dx.doi.org/10.30684/etj.v38i1a.251.

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Recently the Discrete-Wavelet-Transform (DWT) has been represented as signal processing powerful tool to separate the signal into its band frequency components. In this paper, improvement of the steganography techniques by hiding the required message into the suitable frequency band is presented. The results show that the increase of the message length will reduce the Peak Signal to Noise Ratio (PSNR), while the PSNR increases with the increasing the DWT levels. It should be noted that the PSNR reduction was from -13.8278 to -17.77208 when increasing the message length from 161 to 505 characters. In this context, the PSNR is increased from -13.8278 to 7.0554 and from -17.7208 to 1.7901 when the DWT increased from level (1) to level (2).

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Walczyk, Daniel F., and Yong-Tai Im. "A Hydraulically-Actuated Reconfigurable Tool for Flexible Fabrication: Implementation and Control." Journal of Manufacturing Science and Engineering 122, no. 3 (August 1, 1999): 562–68. http://dx.doi.org/10.1115/1.1286258.

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An automatically reconfigurable discrete tool (matrix of pins) has been developed and demonstrated for sheet metal part forming and composite part molding in the aerospace industry. A GUI-based control system positions each of the hydraulically-actuated pins according to a computer model of the intended tool surface. Open-loop position control of individual pins (timing the upward movement of each pin) is possible but accuracy and repeatability are inadequate for most sheet metal forming and composite molding applications. However, closed-loop position control is shown to provide sufficient accuracy and repeatability for these same applications. Once the pin matrix shape is set, it can be made into a rigid forming or molding tool by side clamping with a hydraulic ram. Since the pin ends are spherical in shape, the resulting dimpled tool surface is covered with an interpolating layer of material. The pins can be reset to their lowest position by either withdrawing hydraulic fluid or pushing them down with the setting platen. [S1087-1357(00)01403-9]

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Edidin, Michael. "The organization of cell surface membrane domains." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 804–5. http://dx.doi.org/10.1017/s0424820100155992.

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Cell surface membranes are based on a fluid lipid bilayer and models of the membranes' organization have emphasised the possibilities for lateral motion of membrane lipids and proteins within the bilayer. Two recent trends in cell and membrane biology make us consider ways in which membrane organization works against its inherent fluidity, localizing both lipids and proteins into discrete domains. There is evidence for such domains, even in cells without obvious morphological polarity and organization [Table 1]. Cells that are morphologically polarised, for example epithelial cells, raise the issue of membrane domains in an accute form.The technique of fluorescence photobleaching and recovery, FPR, was developed to measure lateral diffusion of membrane components. It has also proven to be a powerful tool for the analysis of constraints to lateral mobility. FPR resolves several sorts of membrane domains, all on the micrometer scale, in several different cell types.

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Hedlund, J., and A. Lehtovaara. "A parameterized numerical method for generating discrete helical gear tooth surface allowing non-standard geometry." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, no. 6 (June 1, 2008): 1033–38. http://dx.doi.org/10.1243/09544062jmes799.

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Gear analysis is typically performed using calculation based on gear standards. Standards provide a good basis in gear geometry calculation for involute gears, but these are unsatisfactory for handling geometry deviations such as tooth flank modifications. The efficient utilization of finite-element calculation also requires the geometry generation to be parameterized. A parameterized numerical approach was developed to create discrete helical gear geometry and contact line by simulating the gear manufacturing, i.e. the hobbing process. This method is based on coordinate transformations and a wide set of numerical calculation points and their synchronization, which permits deviations from common involute geometry. As an example, the model is applied to protuberance tool profile and grinding with tip relief. A fairly low number of calculation points are needed to create tooth flank profiles where error is <1 μm.

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Krzyzanowski, Michal, and Mark W. Rainforth. "Advances on Modelling of the Tool/Workpiece Interface during High Shear Processing." Materials Science Forum 654-656 (June 2010): 1634–37. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.1634.

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Understanding and prediction of physical phenomena in different scales at the same time that are taking place at the tool/workpiece interface during high shear processing is done in different ways combining the latest finite element (FE) and discrete element (DE) analysis technology. The high shear processing is observed during hot rolling of aluminium, when it produces a highly deformed subsurface layer; and also during friction stir welding (FSW), when it results in significant heat generation and flow. The FE analysis is used for macro-scale simulation while the DE method is applied to simulate meso-scale phenomena taking place in the thin, sometimes a few micron thicknesses, surface layer. Different FE models and numerical techniques combined with DE based transient dynamics approaches are discussed in this work.

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Wu, H. B., Q. P. Sun, and Dun Wen Zuo. "Simulation of Fully Sintering Dental Zirconia Milling Process Based on Discrete Element Method." Key Engineering Materials 568 (July 2013): 49–54. http://dx.doi.org/10.4028/www.scientific.net/kem.568.49.

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Discrete element model of fully sintering dental zirconia was constructed and calibrated. Based on the model, the dynamic process of low-speed milling of zirconia was simulated, and the effects of different cutting speeds, cutting widths and federates on the formation of surface cracks were also analyzed. Results show that residue cracks number and maximum depth increases significantly with increase of the cutting width, while the influence of cutting speed and federates is not distinct. That shows the possibility of high-speed machining on fully sintering dental zirconia with development of coating technology of cutting tool.

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Banko, Antonio, Tedi Banković, Marko Pavasović, and Almin Đapo. "An All-in-One Application for Temporal Coordinate Transformation in Geodesy and Geoinformatics." ISPRS International Journal of Geo-Information 9, no. 5 (May 13, 2020): 323. http://dx.doi.org/10.3390/ijgi9050323.

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Over the years, Global Navigation Satellite Systems (GNSS) have been established in the geosciences as a tool that determines the positions of discrete points (stations) on the Earth’s surface, on global to local spatial scales in a very simple and economical manner. Coordinates obtained by space geodetic measurements ought to be processed, adjusted, and propagated in a given reference frame. As points on the Earth’s surface do not have a fixed position, but rather, are moving with associated velocities, it is inevitable to include those velocities in the coordinate transformation procedure. Station velocities can be obtained from kinematic models of tectonic plate motions. The development and realization of an all-in-one standalone desktop application is presented in this paper. The application unifies coordinate transformation between different realizations (reference frames) of the International Terrestrial Reference System (ITRS) and European Terrestrial Reference System 1989 (ETRS89) following European Reference Frame Technical Note (EUREF TN) recommendations with temporal shifts of discrete points on the Earth’s surface caused by plate tectonics by integrating no-net rotation (NNR) kinematic models of the Eurasian tectonic plate.

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Journal articles on the topic 'Discrete tool surface'

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