Journal articles: 'Computer numerically controlled (CNC) machines'

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Novak-Marcincin, Jozef, and Ludmila Novakova-Marcincinova. "Effective Use of CA System for Control of Water-Jet Cutting Technology." Advanced Materials Research 853 (December 2013): 403–8. http://dx.doi.org/10.4028/www.scientific.net/amr.853.403.

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History of Computer Aided Manufacturing (CAM) becomes from 50th years, when the conception of numerically controlled (NC) machines was designed. This was first impulse for entrance of electronics and later computer technology into the production support. However, more extensive development of CAM systems was enabled by creating the conception of the computer numerically controlled (CNC) production machines which is dated to 1970. Since the CAM systems allow the data about product geometry, which has been created by CAD system, to be used directly for creating NC programs for NC and CNC production machines.

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Zaborski, Andrzej. "Computer-aided preparation of production of products for CNC lathe in an automated production line." Mechanik 92, no. 7 (2019): 456–58. http://dx.doi.org/10.17814/mechanik.2019.7.55.

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The article presents possibility of using contemporary computer systems for computer-aided development of production preparation processes using numerically controlled machines. An example of preparing the production of a drive shaft of a motor shaft on a numerically controlled lathe Defum TAE45 in an automated production line is described. The correctness of the processed process was verified using a profile projector.

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Haridy, Salah, Zhang Wu, and Amro Shafik. "An Educational Scheme for a CNC Drilling Machine." International Journal of Manufacturing, Materials, and Mechanical Engineering 2, no. 2 (2012): 1–11. http://dx.doi.org/10.4018/ijmmme.2012040101.

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Computer numerical control (CNC) involves machines controlled by electronic systems designed to accept numerical data and other instructions, usually in a coded form. CNC machines are more productive than conventional equipment and consequently produce parts at less cost and higher accuracy even when the higher investment is considered. This article proposes an educational scheme for designing a CNC machine for drilling printed circuit boards (PCB) holes with small diameters. The machine consists of three-independently move-fully controlled tables. Output pulses from the personal computer (PC) parallel port are used to control the machine after processing by an interface card. A flexible, responsive and real-time visual C # program is developed to control the motion of the stepper motors. The educational scheme proposed in this article can provide engineers and students in academic institutions with a simple foundation to efficiently build a CNC machine based on the available resources.

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Jywe, W. "Study using position silicon detectors for performance testing of computer numerically controlled machine tools." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 216, no. 5 (2002): 725–33. http://dx.doi.org/10.1243/0954405021520418.

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In this paper, various contouring test systems for computer numerically controlled (CNC) machine tools are reviewed. It is the first time a laser diode and a quadrant sensor have been employed to build a simple contouring measuring system for testing dynamic performance of a CNC machine tool. The experimental work on a CNC machine tool with a Fanuc OM controller for various contouring paths under specified feed rates is carried out. Then, the compensation work is executed with the assistance of this developed contouring system. After the compensation, the contouring error, especially at a high feed rate and small radius, is reduced significantly.

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Sarma, Radha, and Aarthi Rao. "Discretizors and Interpolators for Five-Axis CNC Machines." Journal of Manufacturing Science and Engineering 122, no. 1 (1999): 191–97. http://dx.doi.org/10.1115/1.538896.

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Discretization and interpolation of curves are two frequently adopted practices when machining complex curves using computer numerically controlled (CNC) machines. Both practices stem from the need to sample curves at discrete time intervals corresponding to the sampling period of the CNC machine. This paper proposes new techniques for discretization and interpolation that account for the change of tool orientations in five-axis machining. First, the method for discretization proposed in this paper is based on sampling the curves such that specified contour, feedrate, and orientation errors are not exceeded. Second, the interpolator proposed in this paper will be able to avoid excessive angular speeds arising from sampling the curves based on the feedrate alone. [S1087-1357(00)01401-5]

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BUDZYN, Grzegorz, Janusz RZEPKA, and Pawel KALUZA. "COMPARISON OF STATIC AND DYNAMIC LASER BASED POSITIONING METHODS FOR CHARACTERIZATION OF CNC MACHINES." Journal of Machine Engineering 18, no. 4 (2018): 39–46. http://dx.doi.org/10.5604/01.3001.0012.7631.

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In the paper we compare the laser based measurements of linear parameters of numerically controlled machines. A new dynamic method of measuring machine positioning is described and compared with the widely used static method. The algorithms of the dynamic method are presented and the comparison results of both methods are shown. It is proven that with the new method the measurement time of linear errors of the CNC machines can be reduced significantly. Additionally the machine wear-out in the linear axes can also be easily and efficiently monitored.

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Gunawan, Alexander A. S., and Jimmy Linggarjati. "Pengembangan Program Aplikasi Enhanced Machine Control dengan Python untuk Metode Interpolasi Newton." ComTech: Computer, Mathematics and Engineering Applications 3, no. 1 (2012): 154. http://dx.doi.org/10.21512/comtech.v3i1.2396.

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Nowadays, one of industrial main problems is the flexibility of machines to be customized since they are designed based on certain standard. This research develops software for CNC (Computer Numerically Controlled) machine in order to execute the Newton Interpolation using Python. The platform used in the CNC machine is EMC (Enhanced Machine Control) and GUI (Graphical User Interface) AXIS on the operating system Linux Ubuntu. The Newton interpolation is used to create a curve based on several point determined by user. By converting this curve into G-Code, which could be read by CNC machine, the machine can move according to curve designed by user. This research is an initial study to customize the CNC machine and will continue to fulfill the user needs. This research obtained a program that is able to run well up to 4 input pairs. The higher number inputs will cause the oscillation in the interpolation curve.

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Mo, J. P. T., M. R. Squires, and G. C. Brien. "Real-time automatic statistical control for the grinding process." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 211, no. 3 (1997): 233–37. http://dx.doi.org/10.1243/0954405971516220.

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The highly consistent axes control of current computer numerically controlled (CNC) grinding machines has ensured a high-quality output provided that the process parameters can be kept constant. However, there are many variations in the process that give rise to differences between workpieces. Typical process variations such as tool wear, materials and temperature changes are inevitable and cannot be compensated by advancements in axis servo-control. This paper addresses this problem by applying a high-level control methodology which makes use of real-time statistical process control (SPC) information to determine whether the process has deteriorated due to process variations. Adjustments to machine parameters to offset these changes can then be made. The methodology has been successfully incorporated in a control loop within the controller of the CNC grinders to achieve truly unattended grinding operations.

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Pahk, H. J., and S. W. Lee. "New error correction algorithms minimizing residual positional error for a computer integrated error calibration/correction system in computer numerically controlled machine tools." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 213, no. 7 (1999): 679–86. http://dx.doi.org/10.1177/095440629921300703.

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Linear displacement accuracy is one of the most important factors determining machine tool performance. Software error correction has been generally used for improving the positional accuracy in computer numerically controlled (CNC) machine tools. In this paper, a set of new correction algorithms has been presented for minimizing residual positional errors in CNC machine tools after correction.

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Gupta, Navriti, A. K. Agrawal,, R. S. Walia, and Ranganath Singari. "Hard Turning of AISI D2 Steel In CNC Machining: An Overview." INTERNATIONAL JOURNAL OF ADVANCED PRODUCTION AND INDUSTRIAL ENGINEERING 3, no. 1 (2018): 17–20. http://dx.doi.org/10.35121/ijapie201801125.

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D2 steel is an industrial tool steel. It is widely used in the tool and die industry for making cutting tool inserts, bending inserts, restriking inserts, etc. which can be taken out after their tool life. D2 steel is a very tough steel and difficult to machine also. High generations tool bits like Tungsten carbides and Titanium carbides are required to machine them. The heat treatment follows the machining process. Their machinability is very low. CNC machines are often used to finish them. Often they are machined using programs on UG-NX Uni Graphics(CAM) and DELCAM. And they have to be machined in three steps. Roughing operations, followed by Semi-Finish machining and the last step is finish machining.CNC machining centers are versatile in their applications in metal removal processes. Often they are so modernized that just like many manufacturing operations, metal removal can be automated too. The need for CNC machining arises due to extensive finishing requirements in the aerospace, automotive industries. However, the CNC or Computer and Numerically controlled machining process usage is not limited to these industries only. Tool and Die industry also is heavily dependent on CNC material removal and machining processes as now replaceable inserts are widely used in this industry.

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Holroyd, G., C. Pislaru, and D. G. Ford. "Determination of stiffness and damping sensitivity for computer numerically controlled machine tool drives." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 217, no. 10 (2003): 1165–77. http://dx.doi.org/10.1243/095440603322517171.

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A generalized eigenvalue method is used to determine the undamped and damped natural frequencies, coefficients of damping and mode shapes of a computer numerically controlled (CNC) machine tool drive. The calculated results compare well with the measured results obtained by using vibration analysis equipment. Then the sensitivity of the various modes to changes in the stiffness and damping characteristics of the machine drives is estimated. These values prove to be useful in adjusting the parameters of a hybrid model for a CNC machine tool axis drive in order to alter the simulated results in accordance with the measured results.

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Sobiegraj, Marcin, Piotr Sikora, and Andrzej Zaborski. "Computer-aided preparation of detail production on numerically controlled lathes." Mechanik 92, no. 8-9 (2019): 594–96. http://dx.doi.org/10.17814/mechanik.2019.8-9.76.

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The study presents the possibility of using modern CAD/CAM systems for computer simulation of the process of making the detail on a numerically controlled lathe MIYANO BNA 42GTY. The Alkard CNC Wizard software was used. To verify the correctness of the implemented production process, a coordinate measuring machine Zeiss Prismo 5 with a Renishaw PH-20 head was used. The measurements were carried out using the Modus control software.

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Bedi, S., W. Chernoff, and G. W. Vickers. "Computer-aided Fairing and Direct Numerically Controlled Machining of Ship Hull Hydrodynamic Testing Models." Transactions of the Canadian Society for Mechanical Engineering 12, no. 1 (1988): 43–48. http://dx.doi.org/10.1139/tcsme-1988-0007.

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A computer-aided method of defining and machining 2-metre ship hull forms for hydrodynamic testing is described. The hull shape is faired from the original table of off-sets using a minimum number of smooth three-dimensional parametric skeletal-lines along the length of the boat. A fine set of smoothly blending station-lines is therby formed. The hull shape is preformed in two halves through a lamination process and machined on a three-axis numerically controlled machining (CNC) centre. A carbide-tipped, end-milling cutter is directed along the closely spaced station-lines to rapidly form an accurate hull shape requiring a minimum of hand work. The fairing and machining programs, called G-surf, run on a personal computer and are used to transmit the data and control the CNC machine in real time. The resulting hull shape is symmetrical and far more accurate than manually lofted and preshaped models.

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Cui, Peng, Yuan Xue, and Yuexing Liu. "Manufacturing a ring spun slub yarn using multi-channel drafting technique." Journal of Engineered Fibers and Fabrics 15 (January 2020): 155892502095851. http://dx.doi.org/10.1177/1558925020958518.

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In this paper, we propose a novel method for manufacturing a ring-spun slub yarn through multi-channel drafting using a computer numerically controlled (CNC) ring spinning frame. Through controlling the speeds of the feeding rollers, the apron rollers and the spindle, we can manipulate the blending ratio, linear density and twist of the spun yarn online, offering more degrees of freedom to configure fibers in the spun yarn. Furthermore, we develop a digital control system in conjunction with a CNC ring spinning machine, in which each CNC ring spinning machine serves as a drone machine that receives commands from a central computer. A self-developed management platform is designed to help the client manage these drone machines via online regulation. At last, a series of experiments are conducted to examine the impact of manufacturing parameters on the structures and properties of slub yarn. We found that the descriptive parameters that affect the breaking force of the slub yarn samples are the slub length, slub distance, slub multiplier, and roving ratio. The parameters that affect the breaking elongation are obtained as the slub length, slub distance, slub multiplier, and twist coefficient.

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Verma, Kuldeep, and R. M. Belokar. "Inclusive estimations of ball screw-based CNC feed drive system over positioning and pre-loading factor." Assembly Automation 38, no. 3 (2018): 303–13. http://dx.doi.org/10.1108/aa-07-2017-082.

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Purpose This paper aims to investigate the performance and positioning accuracy of computer numerical controlled (CNC) feed drive system using a ball screw-based pre-loading impact factor. Design/methodology/approach Initially, axial displacement of support bearings has been computed in relation to the different preload values. Among the computed values, a basic rule equation has been developed for the calculation of elongation in the bearings. The value of displacements computed from the developed equation has been considered as a pre-loading value, and its behavior on the feed drive system has been analyzed. Findings The elongation of bearings impacts the positioning accuracy and repeatability of the feed drive system and of CNC machines. Next, an analytical model for the rigorous assessment of CNC feed drive system has been designed and developed. The positioning accuracy of CNC machine in relation with different pre-loading values has been analyzed. Practical implications The results obtained from these investigations enhance the positioning accuracy of CNC machining centers. The optimum pre-loading value has been analyzed among the available ranges, and it has been proposed that optimal results have been achieved at 5 per cent of dynamic load rating. Originality/value This paper proposes improved explorations toward the performance of the CNC machines by optimizing the positioning accuracy through pre-loading. Finally, analytical estimations have been carried out to prove the validity of the proposal.

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O'Farrell, P. N., and R. P. Oakey. "Regional Variations in the Adoption of Computer-Numerically-Controlled Machine Tools by Small Engineering Firms: A Multivariate Analysis." Environment and Planning A: Economy and Space 24, no. 6 (1992): 887–902. http://dx.doi.org/10.1068/a240887.

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In this paper those factors that influence the adoption of computer-numerically-controlled (CNC) machine tools by small mechanical engineering firms in three regions: the South East of England, Scotland, and Wales are investigated. Evidence is presented on CNC machine adoption in the three regions. A logistic regression model of the probability of CNC lathe adoption is developed and a regression model of the data of first adoption is calibrated. Welsh firms recorded lower adoption probabilities than firms based in either South East England or Scotland; and Scottish companies adopted some two years earlier than companies in the other two regions.

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Crawford, H. V., P. S. Unwin, and P. S. Walker. "The CADCAM Contribution to Customized Orthopaedic Implants." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 206, no. 1 (1992): 43–46. http://dx.doi.org/10.1243/pime_proc_1992_206_260_02.

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CADCAM (computer aided design/manufacture) production methods are often associated with mass production; working in the medical field at the Department of Biomedical Engineering, the requirement is for one-off, individualized implants. Using a knowledge-based system, implant designs are produced from X-ray data. Assembly from modular components has greatly reduced the production time of implants for bone tumour cases. CADCAM techniques are also used in the production of custom-made hip replacements using digitized data gathered from radiographs. Femoral canal shape is calculated and the optimal implant designed and manufactured from titanium alloy on the Department's CNC (computer numerically controlled) machines.

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Laddada, S., T. Benkedjouh, M. O. Si- Chaib, and R. DRAI. "Remaining useful life prediction of cutting tools using wavelet packet transform and extreme learning machine." Algerian Journal of Signals and Systems 3, no. 4 (2018): 156–65. http://dx.doi.org/10.51485/ajss.v3i4.72.

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Online tool wear prediction is a determining factor to the success of smart manufacturing operations. The implementation of sensors based Prognostic and Health Management (PHM) system plays an important role in estimating Remaining Useful Life (RUL) of cutting tools and optimizing the usage of Computer Numerically Controlled (CNC) machines. The present paper deals with health assessment and RUL estimation of the cutting tool machines based on Wavelet Packet Transform (WPT) and Extreme Learning Machine (ELM). This approach is done in two phases: a learning (offline) phase and a testing (online) phase. During the first phase, the WPT is used to extract the relevant features of raw data computed in the form of nodes energy. The extracted features are then fed to the learning algorithm ELM in order to build an offline model. In the online phase, the constructed model is exploited for assessing and predicting the RUL of cutting tool. The main idea is that ELM involves nonlinear regression in a high dimensional feature space for mapping the input data via a nonlinear function to build a prognostics model. The method was applied to real world data gathered during several cuts of a milling CNC tool. The performance of the proposed method is evaluated through the accuracy metric. Results showed the significance performances achieved by the WPT and ELM for early detection and accurate prediction of the monitored cutting tools.

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Frank, Matthew C., Richard A. Wysk, and Sanjay B. Joshi. "Determining Setup Orientations From the Visibility of Slice Geometry for Rapid Computer Numerically Controlled Machining." Journal of Manufacturing Science and Engineering 128, no. 1 (2005): 228–38. http://dx.doi.org/10.1115/1.2039100.

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A method for rapid computer numerically controlled (CNC) machining is being developed in an effort to automatically create functional prototypes and parts in a wide array of materials. The method uses a plurality of simple two-and-a-half-dimensional (212-D) toolpaths from various orientations about an axis of rotation in order to machine the entire surface of a part without refixturing. It is our goal to automatically create these toolpaths for machining and eliminate the complex planning traditionally associated with CNC machining. In this paper, we consider a problem that arises in automating this process—visibility to the surface of a model that is rotated about a fourth axis. Our approach involves slicing the computer-aided design (CAD) model orthogonal to the axis of rotation. The slice geometry is used to calculate two-dimensional visibility maps for the set of polygons on each slice plane. The visibility data provides critical information for determining the minimum number and orientation of 212-D toolpaths required to machine the entire surface of a part.

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Yandayan, T., and M. Burdekin. "Development of a laser doppler system for in-process evaluation of diameters on computer numerical controlled turning machines." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 212, no. 3 (1998): 183–94. http://dx.doi.org/10.1243/0954405981515608.

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The diameter of the workpiece is measured, while the workpiece is located on the CNC (computer numerical controlled) turning machine, using a new laser instrument and technique. The optical instrument is based on the laser Doppler principle, using an He—Ne laser as a light source. It obtains data by detecting the scattered light from the surface of a rotating workpiece, processing this data with respect to the rotation of the spindle and providing a value representing the workpiece diameter. The basic resolution of the system depends on the wavelength of the laser and geometry of the optics. Higher resolution can be achieved by obtaining the data from the workpiece surface over more than one complete revolution of the spindle. The resolution for one revolution of the spindle is 0.5μm and for ten 0.05μm. The measurement system is also integrated with the CNC turning machine, particularly for autofocusing of the instrument. The instrument is mounted on the tool holder of the CNC turning machine, which is focused by means of a tool offset parameter for non-contact measurement of each different diameter. Autofocusing is carried out using the MI5 machine tool interface unit which is already established for the Renishaw probe system, according to CNC part programming. The performance of the proposed technique and instrument is verified through the experiments.

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Hu, Si Qian, Hai Ping Wang, Yu Min Zhang, and Xin Zou. "Polytetrafluoroethylene Mesh for Many Types of Blueprinting Machine: Preparation and Characterization." Advanced Materials Research 317-319 (August 2011): 48–52. http://dx.doi.org/10.4028/www.scientific.net/amr.317-319.48.

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Adopting domestic polytetrafluoroethylene (PTFE) turning plate as materials, a new isosceles triangle macroporous mesh was designed. The correspond mould and the special fixtures for continuous punching of ultra-thin plastic sheet were successfully developed. The PTFE mesh was manufactured through computer numerically controlled (CNC) punch. In terms of electronic universal testing machines and microcomputer differential thermal balance, mechanical properties and thermostability of the PTFE mesh were studied. The results indicated that the tensile strength of PTFE mesh is 11.98 MPa which is greater than the literature value of 7.77 MPa, and its heat-resisting performance is excellent without decomposition prior to 312 oC.

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Lim, C. K., and M. Burdekin. "Rapid volumetric calibration of coordinate measuring machines using a hole bar artefact." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 216, no. 8 (2002): 1083–93. http://dx.doi.org/10.1243/095440502760272368.

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The paper reports on the development of a new rapid volumetric accuracy calibration system for multiaxis coordinate measuring machines (CMMs). The system utilizes a calibrated mechanical artefact, in the form of a 540mm long I-beam hole bar. The 21 effective parametric error components for a three-axis machine can be obtained by probing the artefact when it is placed at 17 specified orientations within the measuring volume. The parametric errors are then further transformed into the CMM volumetric error by applying formulae derived from the rigid-body motion for the structural configuration of the CMM. Software has been developed to automate the probing of the artefact, data acquisition and the analysis of the parametric errors. Options for graphical and numerical data output of the volumetric error map is also included. Practical calibration tests and results from a moving bridge CNC (computer numerically controlled) CMM are shown, where the overall time for the calibration process, including equipment set-up time, was found to be less than two hours.

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Wang, Jianchen, Tao Jiang, Junquan Shen, Junhao Dai, Zequan Pan, and Xiaolei Deng. "Thermal Error Compensation of Spindle System of Computer Numerically Controlled Machine Tools Through Experiments and Modeling." Instrumentation Mesure Métrologie 19, no. 4 (2020): 301–9. http://dx.doi.org/10.18280/i2m.190408.

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This paper attempts to solve the insufficient machining precision of computer numerically controlled (CNC) machine tools, which is induced by the thermal error of the spindle. Firstly, the relationship between machining error and thermal sensitive points was analyzed through experiments. On this basis, the backpropagation neural network (BPNN) was improved by particle swarm optimization (PSO). Next, the improved network (PSO-BPNN) was used to build a thermal error compensation (TCE) model for the spindle of machine tools. Taking VM-500T precision machine tool as the object, the temperature data were grouped through the optimization based on thermal imaging, grey relational analysis (GRA), and fuzzy clustering, to determine the temperature sensitive items that causes the thermal error. To speed up network convergence, the PSO algorithm was introduced to optimize the number of hidden layers and the number of hidden layer nodes of the BPNN, lifting the network from the local optimum trap. To enhance the generalization ability, the weights and thresholds of the BPNN were also improved by the PSO. After that, two TCE models were established for the spindle of the machine tool, respectively based on the original BPNN and PSO-BPNN. Contrastive experiments show that the PSO-BPNN TCE model achieved the better generalization ability, and improved the prediction accuracy of the machining error of the CNC machine tool.

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Racz, Sever-Gabriel, Radu-Eugen Breaz, and Lucian-Ionel Cioca. "Hazards That Can Affect CNC Machine Tools during Operation—An AHP Approach." Safety 6, no. 1 (2020): 10. http://dx.doi.org/10.3390/safety6010010.

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CNC (computer numerically controlled) machine tools are highly advanced technological systems, used to machine parts by means of metal cutting processes. Their structure and kinematics are very complex, involving accurate coordinated motions on three to five axes. Operating CNC machine tools is a complicated process, which can easily be affected by errors. Nowadays, safety systems and devices are developed in order to make this process safer and more user friendly. Modern CNC controllers are designed to deal with obvious sources of hazards, such as overloads (by means of various sensor systems) and collisions (by checking the NC code syntax and simulating it on the machine). However, despite of these safety systems, various unwanted events still occur during machining operations on CNC machine tools. These means that there are still certain hazards, not so obvious, which can severely affect the operation of CNC machine tools. This work tries to identify and hierarchize the above-mentioned hazards by using an AHP (analytic hierarchy process) approach. The results of the AHP emphasize which hazard has the biggest influence upon the CNC machine tools operation and consequently should be avoided. The results of this work could be used by the machine tools designers to develop new safety features for the existing CNC controllers. Also, the users of the machine tools could focus some of the safety measures during the machining process upon the most significant hazards pointed by the results of the research.

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Domek, Stefan, Paweł Dworak, Marek Grudziński, and Krzysztof Okarma. "Calibration of Cameras and Fringe Pattern Projectors in the Vision System for Positioning of Workpieces on the CNC Machines." Solid State Phenomena 199 (March 2013): 229–34. http://dx.doi.org/10.4028/www.scientific.net/ssp.199.229.

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Application of machine vision in automation, robotics and mechatronic systems is one of the most rapidly developing areas of industrial and applied computer science. The vision system presented in the paper can be used for automatic positioning of the workpieces on the numerically controlled machines. The idea of the system is based on the 3D scanning using the fringe patterns approach [ but its accuracy strongly depends on the lighting conditions and the proper calibration of the whole vision system. The most crucial elements for the calibration are both cameras and structural light projectors, as well as the overall geometrical configuration (external parameters in the common coordinate system) and the compensation of the brightness nonlinearities introduced by the structural light sources. In the paper some methods used for the calibration of the experimental system and obtained results are presented.

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Rajenthirakumar, D., and R. Sridhar. "Single Point Incremental Sheet Forming of Polymer on Computer Numerically Controlled (CNC) Milling Machine Tool." Key Engineering Materials 622-623 (September 2014): 420–26. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.420.

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The idea of incrementally forming sheet metal with a single point tool, called ‘dieless forming’, was patented by Leszak [1] well before it was technically feasible. There have been many studies, which have lead to the present situation [2-9]. The new processes are attractive because manufacturing sheet metal can be accomplished by any facility having a three-axiscncmill. Sheet metalspifis an innovative, flexible sheet metal-forming technology that uses principles of layered manufacturing. It transforms the complicated geometry information into a series of parameter of two-dimensional layers and then the plastic deformation is carried out layer-by-layer through the computer numerically controlled. The basic principle ofspif(Fig. 1) is that the forming tool moves around the outline of the part along the predefined tool path and extrudes the sheet metal point by point so that the local plastic deformations occur incrementally [8, 10]. The forming tool paths have a great effect on the surface quality, forming time and dimensional accuracy. Although the movement mode of the forming tool is similar to one of the cutters in thecncmilling machine, the forming process based on the plastic deformation and milling process is totally different, so the requirements for the tool paths are different. As a result, there are some specific characteristics which should be considered in forming tool path generation. The goal of this paper is to evaluate the possibility of producing low-cost polymer sheet components by means ofspif. Three different thermoplastic materials were incrementally formed on a conventionalcncmilling machine. Experiments are conducted to determine the formability, failure modes and significant process parameters. Even though considerable amount of research work has been done in the field, these aspects are not completely defined and only limited number of materials has been tested.

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Ford, DG, A. Myers, F. Haase, S. Lockwood, and A. Longstaff. "Active vibration control for a CNC milling machine." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 2 (2013): 230–45. http://dx.doi.org/10.1177/0954406213484224.

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There is a requirement for improved three-dimensional surface characterisation and reduced tool wear when modern computer numerical control (CNC) machine tools are operating at high cutting velocities, spindle speeds and feed rates. For large depths of cut and large material removal rates, there is a tendency for machines to chatter caused by self-excited vibration in the machine tools leading to precision errors, poor surface finish quality, tool wear and possible machine damage. This study illustrates a method for improving machine tool performance by understanding and adaptively controlling the machine structural vibration. The first step taken is to measure and interpret machine tool vibration and produce a structural model. As a consequence, appropriate sensors need to be selected and/or designed and then integrated to measure all self-excited vibrations. The vibrations of the machine under investigation need to be clearly understood by analysis of sensor signals and surface finish measurement. The active vibration control system has been implemented on a CNC machine tool and validated under controlled conditions by compensating for machine tool vibrations on time-varying multi-point cutting operations for a vertical milling machine. The design of the adaptive control system using modelling, filtering, active vibration platform and sensor feedback techniques has been demonstrated to be successful.

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Thilmany, Jean. "Beyond Step." Mechanical Engineering 129, no. 10 (2007): 41–43. http://dx.doi.org/10.1115/1.2007-oct-5.

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This article reviews modern-day computer numerically controlled machines are no longer modern enough. The 50-year-old G and M codes that drive those machines cannot transfer valuable geometric information from CAD and CAM systems, according to a group of experts who are advocating for widespread use of the recently approved STEPNC standard. With the new standard, CAD and CAM applications have the capability to send product information to CNC machines. Today’s global engineering companies commonly pass CAD files back and forth. There are a number of ways for suppliers to translate their own CAD files into a format that original equipment manufacturers can read. The STEP and IGES translation programs have the same problems as human translators. Sometimes, there just is not a one-to-one correlation between words or, in the case of CAD systems, pieces of product data, like geometry features or attributes. IGES and STEP standards have to evolve as fast as today’s engineering technologies are evolving.

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Poutsma, Erik, and Aad Zwaard. "Programming CNC-Equipment—The Effects of Automation in Small Industrial Enterprises." International Small Business Journal: Researching Entrepreneurship 7, no. 2 (1989): 35–43. http://dx.doi.org/10.1177/026624268900700203.

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ERIK POUTSMA and Aad Zwaard are research associates at the Economic Research Institute for Small-and Medium-sized businesses in Zoetermeer, the Netherlands. This paper focusses on the effects of new technologies in small-and medium-sized industrial businesses. The study is based on a survey of 780 enterprises in different industries and three case studies in the metals industry. One of the crucial indicators to judge the changes in work organisation and job content is where and by whom computer numerically controlled (CNC) machines are programmed. In general it can be stated that the smaller the scale of the enterprise and size of batches, the greater the number of tasks and responsibilities on the part of the operator. Furthermore, in small firms with variable runs of production, the machine operators carry out programming functions as well as tasks of optimalisation, adjustment and quality control. The number of different tasks also depends on the level of education and skills of the operator, which is slightly higher in small firms. One of the main findings is that new technologies leave room for organisational choices concerning the quality of work. If small firms are to be able to compete in the future much depends on the way they make use of modern technologies. The first concern when automation is introduced is to keep the multi-skill and autonomous character of jobs intact.

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Chen, Sung-Gwang, A. Galip Ulsoy, and Yoram Koren. "Error Source Diagnostics Using a Turning Process Simulator." Journal of Manufacturing Science and Engineering 120, no. 2 (1998): 409–16. http://dx.doi.org/10.1115/1.2830141.

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To improve productivity and quality in machining, it is necessary to understand the interactions among machine tool components and the cutting process. This paper presents a model that characterizes interactions among the subsystems of a computer numerically controlled (CNC) lathe. The model is combined with a cutting force model to obtain a comprehensive turning simulator that simulates the cutting forces and part dimensions. A series of calibration experiments are proposed and implemented for process simulation. The simulation results are good when compared with experimental measurements. The interactions among the subunits of a CNC lathe and the cutting process are found to be potentially important.

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Meyer, Edgar F. "Digital Design of Molecular Sculptures and Abstractions." Leonardo 44, no. 1 (2011): 22–28. http://dx.doi.org/10.1162/leon_a_00089.

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While tactile models have been used to describe molecular structures for over a century, the sculpting of structural models is a recent phenomenon. Following X-ray coordinate selection, the author uses modeling software and a computer numerically controlled (CNC) milling machine to create precisely scaled, tactile molecular sculptures. The challenge is to inspire the general public to appreciate the aesthetic aspects of molecular architecture and to reveal the magnificence of nature on the molecular scale.

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Pop, Alina Bianca, and Aurel Mihail Ţîţu. "Applied study on the rotational molding and processing technology of rotational molds." MATEC Web of Conferences 343 (2021): 04005. http://dx.doi.org/10.1051/matecconf/202134304005.

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Computer-aided manufacturing involves a set of computerized activities related to the preparation, launch and follow-up of manufacturing. Computer-aided manufacturing is a tool that allows the use of 3D models based on computer-aided design. This paper addresses the process of rotational formation, with an effective focus on the technology of processing a rotational mold using CAM simulation as a research method. In this sense, the right choice of CNC and cutting tools is essential. The use of numerically controlled machine tools and high-performance cutting tools reduces the number of operations. The manufacturing route realized is specific to the parts machining on numerical control machine, with multiple possibilities such as the execution on a single machine of all the necessary operations to create the mold. PowerMILL gives the user the flexibility to generate thisheir NC programs and ensures the use of the most efficient processing method without having to wait for the complete calculation. A number of different strategies, from the wide range that PowerMILL has, are compared using a high tolerance so that they can be calculated quickly. In this study, the strengths of the CNC are highlighted based on experimental research, features that make this machine a very productive one, saving time, energy and, implicitly, low execution costs.

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ARYA, SUNIL, SIU-WING CHENG, and DAVID M. MOUNT. "APPROXIMATION ALGORITHM FOR MULTIPLE-TOOL MILLING." International Journal of Computational Geometry & Applications 11, no. 03 (2001): 339–72. http://dx.doi.org/10.1142/s0218195901000535.

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Milling is the mechanical process of removing material from a piece of stock through the use of a rapidly spinning circular milling tool in order to form some desired geometric shape. An important problem in computer-aided design and manufacturing is the automated generation of efficient milling plans for computerized numerically controlled (CNC) milling machines. Among the most common milling problems is simple 2-dimensional pocket milling: cut a given 2-dimensional region down to some constant depth using a given set of milling tools. Most of the research in this area has focused on generating such milling plans assuming that the machine has a tool of a single size. Since modern CNC milling machines typically have access to a number of milling tools of various sizes and the ability to change tools automatically, this raises the important optimization problem of generating efficient milling plans that take advantage of this capability to reduce the total milling time. We consider the following multiple-tool milling problem: Given a region in the plane and a set of tools of different sizes, determine how to mill the desired region with minimum cost. The problem is known to be NP-hard even when restricted to the case of a single tool. In this paper, we present a polynomial-time approximation algorithm for the multiple-tool milling problem. The running time and approximation ratio of our algorithm depend on the simple cover complexity (introduced by Mitchell, Mount, and Suri) of the milling region.

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Cioca, Lucian-Ionel, Radu-Eugen Breaz, and Sever-Gabriel Racz. "Selecting the Safest CNC Machining Workshop Using AHP and TOPSIS Approaches." Safety 7, no. 2 (2021): 27. http://dx.doi.org/10.3390/safety7020027.

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Machining operations on computer numerically controlled (CNC) machine tools are essential for the machining industry. Most of these operations take place in machining workshops. Safety issues in machining workshops shops can affect not only the health of the operators, which is extremely important, but also the productivity of the process and the accuracy of the parts. The research presented in this article addresses the issue of evaluating the safety of a CNC machining workshop, using a combined approach based on the analytic hierarchy process (AHP) and technique for order performance by similarity to ideal solution (TOPSIS) methods. A set of four evaluation criteria was proposed and the methods of processing the information for each criterion were used to extract the significant data needed for the evaluation. The proposed method was used to select the safest CNC machining workshop out of a total of three considered for assessment.

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Cui, Peng, Yuan Xue, and Yuexing Liu. "Manufacturing Color-Blended Slub Yarn: Computer Numerically Controlled Ring-Spinning Frame and Kubelka-Munk Double Constant Theory." AATCC Journal of Research 8, no. 3 (2021): 8–16. http://dx.doi.org/10.14504/ajr.8.3.2.

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In the present work, we used the computer numerically controlled (CNC) ring-spinning frame to produce the color-blended slub yarns made from three different colored rovings with a 10% blending gradient. The blending ratio of rovings was determined by Kubelka-Munk (K-M) double constant theory. The as-manufactured yarns were made into knit fabrics with a circular knitting machine. The relative value method was used to solve the absorption and scattering coefficients of each colored fiber, and the least-square method was used to solve for the blending ratio of color-blended slub yarn. The results show that the average color difference between predicted and measured L*a*b* values was 1.74, and the error of the blending ratio was 7.38%, which are within the acceptable ranges for color matching of yarns.

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Sekou, Singare. "Manufacture of Custom Contoured Seat Cushions Using Computer-Aided Design Computer-Aided Manufacturing (CAD/CAM) Technique." Advanced Materials Research 201-203 (February 2011): 342–46. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.342.

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In the rehabilitation engineering area, the pressure ulcer prevention is an important and healthy problem, especially for people with the spinal cord injured (SCI). This paper aim to develop a computer aided design and computer aided manufacture (CAD/CAM) method to manufacture custom cushions to prevent pressure ulcer. A patient’s buttock was digitized using 3D laser scanner, and the captured buttock data was processed in reverse engineering environment to generate the 3D surface model of the buttock. The 3D surface model of the buttock is imported into Unigraphics software to create the solid model; then, a flat rectangle that represents the cushion was generated under the buttock to create the buttock-cushion system. Based on the load-deformation relation of cushion materials acquired by the test, the depth of cut of the cushion was established and a CAD model of cushion shape was created through a Boolean subtraction. The CAD model of the contour is post-processed into code that the numerically controlled milling machine (CNC milling) can use to machine the cushion.

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Weir, D. J., M. J. Milroy, C. Bradley, and G. W. Vickers. "Reverse Engineering Physical Models Employing Wrap-Around B-Spline Surfaces and Quadrics." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 210, no. 2 (1996): 147–57. http://dx.doi.org/10.1243/pime_proc_1996_210_100_02.

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Reverse engineering involves digitizing a three-dimensional model or part, by means of a tactile or non-contact optical sensor, converting the data to a CAD (computer aided design) database description and manufacturing by CNC (computer numerical controlled) machines. This paper demonstrates an effective approach to the reverse engineering of physical models by employing a three-dimensional laser scanning system in conjunction with surface-fitting software developed by the authors. Accurate surface data are collected by the laser scanner and then input to the surface-fitting software. Surface entities such as B-spline and quadric functions are employed to build the CAD model. The CAD model is compatible with popular design and manufacturing software packages. A telephone receiver is used to illustrate the efficiency of the process.

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Oakey, R. P., and P. N. O'Farrell. "The Regional Extent of Computer Numerically Controlled (CNC) Machine Tool Adoption and Post Adoption Success in Small British Mechanical Engineering Firms." Regional Studies 26, no. 2 (1992): 163–75. http://dx.doi.org/10.1080/00343409212331346871.

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Li, Ling, Qiangqiang Yun, Zhiqiang Li, Yin Liu, and Changyong Cao. "A New Contact Model of Joint Surfaces Accounting for Surface Waviness and Substrate Deformation." International Journal of Applied Mechanics 11, no. 08 (2019): 1950079. http://dx.doi.org/10.1142/s1758825119500790.

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The joint surfaces in the computer numerically controlled (CNC) machines play a crucial role in transmitting load and energy in operations. In this paper, a new contact model between rough surfaces of a joint is proposed by considering the influence of surface waviness and substrate deformation. A contact model for a single asperity system is first established, in which the asperity and substrate deformations are calculated based on the Hertz theory. Then, it is extended to an entire rough surface by a statistical method, where the contact of rough surfaces is treated as the contact between a smooth waviness and a rough surface. The numerical results showed that when contact deformation is constant, the real contact area and the normal load of joint surfaces increase with increasing radius of the waviness peak while the normal load decreases with the increase of surface roughness. When a rough surface contains a coating layer or a surface film, the deformation of the joint surface has to consider both substrate deformation and asperity deformation. The substrate deformation will generate larger influence for a stiffer or harder coating. Compared with other models, the results obtained from the proposed model show better agreements with the experimental data.

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Lho, T.-J., and S.-J. Na. "A Study on an Improved Direct Search Interpolation Method for Two-Axis CNC Thermal Cutting Systems." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 206, no. 1 (1992): 67–76. http://dx.doi.org/10.1243/pime_proc_1992_206_057_02.

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A microcomputer-based reference pulse software interpolator, which can be effectively applied for two-axis computer numerical control (CNC) systems such as those used in plasma arc cutting and laser beam cutting machines, is proposed in the present study. The proposed interpolation method is based upon searching in two or three directions for the minimum path error, while the axes of motion do not move simultaneously in the stairs approximation method and the basis for selecting an interpolating point is not related to any criteria of path error in the digital differential analyses (DDA) method. Accordingly, this method has many advantages over the other two competing methods, such as small maximum path error of only a half basic length unit (BLU), uniform velocity along the cutter path, high degree of path smoothness and maximum velocity allowable. Since the velocity of the proposed CNC system is controlled through adjusting two interrupt interval times at each interpolation step, a constant velocity can be maintained along any cutting path. The proposed interpolation algorithm is very simple and can be easily applied for the practical CNC systems, since it is based on transforming the interpolating paths in all interpolating cases to those in one typical case.

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Jaiganesh, V., B. Yokesh Kumar, P. Sevvel, and A. J. Balaji. "Optimization of process parameters on commercial mild steel using taguchi technique." International Journal of Engineering & Technology 7, no. 1.1 (2017): 138. http://dx.doi.org/10.14419/ijet.v7i1.1.9213.

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In the present scenario of bulk manufacturing where Metal Removal Rate (MRR), Chip Thickness Ratio (CTR) and Surface Roughness (SR) is of significant importance in manufacturing the component using CNC (computer numerical controlled) machines. Nine experiments were conducted based on orthogonal array. General linear model has been generated for all the three output parameters such as (MRR, Chip Thickness Ratio surface roughness) versus input parameters (speed, time, depth of cut). The statistical method called the analysis of variance (ANOVA) is applied to find the critical factor. The Main effects of S/N ratio values are found and plotted in the form of graph. The optimized value is found for speed, time, and depth of cut by using “MINITAB” software. By using this optimized value the efficient metal cutting can be done in commercial mild steel.

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Nobre, Joao P., J. H. Stiffel, W. Van Paepegem, et al. "Quantifying the Drilling Effect during the Application of Incremental Hole-Drilling Technique in Laminate Composites." Materials Science Forum 681 (March 2011): 510–15. http://dx.doi.org/10.4028/www.scientific.net/msf.681.510.

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In this work, a methodology to quantify the effect of the drilling operation, during the application of the incremental hole-drilling technique (IHD) for measuring residual stresses in laminate composites, in particular, the polymer matrix composites (PMC), is presented. This technique will allow the optimization of the drilling procedures and its parameters, enabling the quantification of the drilling effect. This quantification is obtained by using an experimental calibration procedure followed by a numerical simulation of the whole process. The direct comparison of the experimental and numerical results will allow quantifying the effect of the drilling operation. As example, the methodology was applied to the case of carbon/epoxy cross-ply laminate [0°/90°]5s. The holes have been made by using two different drilling procedures, but the same tool geometry. High speed milling powered by air compression, a process usually employed in the case of the application of hole-drilling technique to metal alloys and a conventional computer numerically controlled (CNC) milling machine, were used. The results seem to show that incremental hole-drilling could be a reliable technique to determine residual stresses in fibre-reinforced polymers.

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Luo, J. X., D. L. Joynt, and K. A. Stelson. "Control of the Fabrication of Long Slender Workpieces of Arbitrary Shape—Part I: Open-Loop Control of the Multi-Axis Bending Process." Journal of Dynamic Systems, Measurement, and Control 118, no. 3 (1996): 540–48. http://dx.doi.org/10.1115/1.2801178.

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Computer numerically controlled (CNC) multi-axis bending is a new metal-forming process used to fabricate long slender workpieces of arbitrary shape and cross section. This process can achieve higher productivity and flexibility than conventional forming processes. However, a manual trial-and-error process has been adopted to find control commands that would produce accurate part shape in mass production. This traditional approach which completely relies on the skills of the machine operator often results in long lead-times and great cost in setting up the bender for a new part. A new methodology has been developed, using the geometrical concept of intrinsic part representation, to model the workpiece and fabricating process. The process model compensates for elastic and fabricating process. The process model compensates for elastic springback, and can be used to predict a set of initial multi-axis control commands which will eventually converge to the final commands through a feedback process. The effectiveness of the method has been demonstrated experimentally.

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Abd-Alrazzaq, Mohamed, Mahmoud Ahmed, and Mohamed Younes. "Experimental Investigation on the Geometrical Accuracy of the CNC Multi-Pass Sheet Metal Spinning Process." Journal of Manufacturing and Materials Processing 2, no. 3 (2018): 59. http://dx.doi.org/10.3390/jmmp2030059.

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The geometrical accuracy of multi-pass sheet metal spinning products is crucial in many applications. Aerospace, petroleum, and chemical industries motivated the development of modern spun components of complicated shapes with special functionality, but a substantial research lag exists behind this progress. Due to the localized plastic deformation involved, careful control of dimensions and form is required in spinning procedures. In this study, two sets of experiments were implemented for cup manufacturing using a retrofitted computer numerically controlled (CNC) spinning machine to identify the critical factors affecting product geometry and reveal their influence on the shape accuracy of the spun cups. The first set is a screening experiment to determine the most significant parameters and the second provides the optimum processing conditions affecting cup quality. The feed ratio, number of spin-forming passes, spinning ratio, and lubrication were found to have the most important effect on the geometry of the spun cups. Optimum quality with a higher processing speed (productivity) was achieved under a lubricated condition using a larger number of spin-forming passes at a high feed ratio, diminishing the commonly adopted rule of slow spinning for accurate products and reflecting a significance for state-of-the-art spinning practice. The findings of this paper introduce a basis for a spinning quality database.

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Dobrzański, Leszek A., Lech B. Dobrzański, Anna Achtelik-Franczak, and Joanna Dobrzańska. "Application Solid Laser-Sintered or Machined Ti6Al4V Alloy in Manufacturing of Dental Implants and Dental Prosthetic Restorations According to Dentistry 4.0 Concept." Processes 8, no. 6 (2020): 664. http://dx.doi.org/10.3390/pr8060664.

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This paper presents a comparison of the impact of milling technology in the computer numerically controlled (CNC) machining centre and selective laser sintering (SLS) and on the structure and properties of solid Ti6Al4V alloy. It has been shown that even small changes in technological conditions in the SLS manufacturing variant significantly affect changes from two to nearly two and a half times in tensile and bending strengths. Both the tensile and bending strength obtained in the most favourable manufacturing variant by the SLS method is over 25% higher than in the case of cast materials subsequently processed by milling. Plug-and-play SLS conditions provide about 60% of the possibilities. Structural, tribological and electrochemical tests were carried out. In vitro biological tests using osteoblasts confirm the good tendency for the proliferation of live cells on the substrate manufactured under the most favourable SLS conditions. The use of SLS additive technology for the manufacturing of dental implants and abutments made of Ti6Al4V alloy in combination with the digitisation of dental diagnostics and computer-aided design and manufacture of computer-aided design/manufacturing (CAD/CAM) following the idea of Dentistry 4.0 is the best choice of technology for manufacturing of prosthetic and implant devices used in dentistry.

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Chen, C.-K., S.-T. Chiou, Z.-H. Fong, C.-K. Lee, and C.-H. Chen. "Mathematical model of curvature analysis for conjugate surfaces with generalized motion in three dimensions." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 215, no. 4 (2001): 487–502. http://dx.doi.org/10.1243/0954406011520797.

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A general mathematical model is proposed to determine the direct relations between the principal curvatures and directions of two conjugate surfaces in continuous tangency along a line at every instant. Without any assumption regarding the motion of mating surfaces, this model, created on the basis of kinematics, the theory of gearing and differential geometry, is especially suitable for calculating the curvatures of a surface generated on a computer numerically controlled (CNC) machine with surface modifications by non-constant-speed supplemental correcting motions. The model has simplified dramatically the calculation of curvatures by comparison with the differential geometry approach. The principal curvatures of a generated surface and dimensions of contact ellipses can be obtained by the model without the need for complicated equations of the generated surface. For verification of the model, a helical gear set comprising a gear with involuted teeth and a pinion with modified circular arc teeth is investigated. The tooth contact analysis (TCA) technique is also applied to study the shift of bearing contacts and dimensions of contact ellipses under three different kinds of generation setting.

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Owusu-Ansah, Ebenezer, and Colin Dalton. "Fabrication of a 3D Multi-Depth Reservoir Micromodel in Borosilicate Glass Using Femtosecond Laser Material Processing." Micromachines 11, no. 12 (2020): 1082. http://dx.doi.org/10.3390/mi11121082.

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Micromodels are ideal candidates for microfluidic transport investigations, and they have been used for many applications, including oil recovery and carbon dioxide storage. Conventional fabrication methods (e.g., photolithography and chemical etching) are beset with many issues, such as multiple wet processing steps and isotropic etching profiles, making them unsuitable to fabricate complex, multi-depth features. Here, we report a simpler approach, femtosecond laser material processing (FLMP), to fabricate a 3D reservoir micromodel featuring 4 different depths—35, 70, 140, and 280 µm, over a large surface area (20 mm × 15 mm) in a borosilicate glass substrate. The dependence of etch depth on major processing parameters of FLMP, i.e., average laser fluence (LFav), and computer numerically controlled (CNC) processing speed (PSCNC), was studied. A linear etch depth dependence on LFav was determined while a three-phase exponential decay dependence was obtained for PSCNC. The accuracy of the method was investigated by using the etch depth dependence on PSCNC relation as a model to predict input parameters required to machine the micromodel. This study shows the capability and robustness of FLMP to machine 3D multi-depth features that will be essential for the development, control, and fabrication of complex microfluidic geometries.

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Yudianto, Yudianto. "AN OVERVIEW OF DIRECT OR DISTRIBUTED NUMERICAL CONTROL IN COMPUTER NUMERICAL CONTROL APPLICATIONS." Journal of Mechanical Science and Engineering 7, no. 2 (2021): 025–29. http://dx.doi.org/10.36706/jmse.v7i2.38.

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Direct numerical control is also known as distributed numerical control (also abbreviated DNC), is a common manufacturing term for networking CNC machine tools. On some CNC machine controllers, the available memory is too small to contain the machining program (for example machining complex surfaces), so in this case the program is stored in a separate computer and sent directly to the machine, one block at a time. If the computer is connected to a number of machines it can distribute programs to different machines as required. Usually, the manufacturer of the control provides suitable DNC software. However, if this provision is not possible, some software companies provide DNC applications that fulfill the purpose. DNC networking or DNC communication is always required when Computer-Aided Manufacturing (CAM) programs are to run on some CNC machine control. Wireless DNC is also used in place of hard-wired versions. Controls of this type are very widely used in industries with significant sheet metal fabrication, such as the automotive, appliance, and aerospace industries. A DNC system has to fulfill two basic tasks such as first guaranteeing secure, timely data transfer from and to the CNC controllers, secondly administering many thousands of NC programs.

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Jinfeng, Li, Wang Liping, and Guan Liwen. "Analysis of the Vertical Stiffness of Rolling Guide that Involves the Elastic Deformation of Carriage Skirt." Open Mechanical Engineering Journal 9, no. 1 (2015): 726–32. http://dx.doi.org/10.2174/1874155x01509010726.

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Static stiffness is an important indicator of the performance of a rolling guide, having direct influence on the stiffness and precision of computer numerically controlled (CNC) machine tools. After preloading the rolling guide, an outward elastic deformation is generated at the carriage skirt, which leads to a decrease in the static stiffness of the rolling guide. Therefore, there would be relatively large errors between the numerical results and the experimental results when the carriage is considered as a rigid body. In this paper, an analytical method for estimating the vertical stiffness of rolling guide was proposed, which took into account the elastic deformation in the carriage skirt. The contact elastic deformation model under loads was given using Hertz’s contact theory, from which the numerical results for the vertical stiffness of the surface of the rolling guide was calculated when the elastic deformation in the carriage skirt was ignored. The calculation method for the carriage skirt deformation was given using the finite element method, from which the numerical relationship between the deformation and the contact force was obtained after fitting adjustment. An analytical model was therefore established and took into account the elastic contact deformation and the carriage skirt deformation, and a universal calculation method was proposed for vertical stiffness. Experimental results show that compared to those not involving the deformation, the numerical results for vertical stiffness involving the carriage skirt deformation matched more closely with the experimental results, with relative errors no greater than 6.5%.

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Pietrusewicz, Krzysztof. "Metamodelling for Design of Mechatronic and Cyber-Physical Systems." Applied Sciences 9, no. 3 (2019): 376. http://dx.doi.org/10.3390/app9030376.

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The paper presents the issue of metamodeling of Domain-Specific Languages (DSL) for the purpose of designing complex mechatronics systems. Usually, one of the problems during the development of such projects is an interdisciplinary character of the team that is involved in this endeavour. The success of a complex machine project (e.g. Computer Numerically Controlled machine (CNC), loading crane, forestry crane) often depends on a proper communication between team members. The domain-specific modelling languages developed using one of the two approaches discussed in the work, lead to a machine design that can be carried out much more efficiently than with conventional approaches. Within the paper, the Meta-Object Facility (MOF) approach to metamodeling is presented; it is much more prevalent in modern modelling software tools than Graph-Object-Property-Relationship-Role (GOPRR). The main outcome of this work is the first presentation of researchML modelling language that is the result of more than twenty ambitious research and development projects. It is effectively used within new enterprises and leads to improved traceability of the project goals. It enables for fully-featured automatic code generation which is one of the main pillars of the agile management within mechatronic system design projects.

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Journal articles on the topic 'Computer numerically controlled (CNC) machines'

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