COMPLEX-SHAPED PARTS GRINDING TECHNOLOGY INFORMATION ENSURING

2020 ◽  
Vol 3 (4) ◽  
pp. 246-262
Author(s):  
Natalia V. Lishchenko ◽  
Vasily Petrovich Larshin

A method of computer-aided design and manufacture of complex-shaped parts of machines and implants from difficult-tomachine materials (titanium, cobalt-chromium alloys, zirconium dioxide, etc.) has been developed, based on the principles of building an integrated CAD/CAM/CAE system of computer-aided designing and a hierarchical intelligent numerical control system. It is shown that kinematical mechanisms created over the past several centuries do not allow reproducing with the required accuracy the joints movement of living organisms for their use in biomedical implantation technologies. Therefore, the worn out joints of living organisms are reconstructed by adding complex-shaped parts from these difficult-to-machine materials. Information about the geometric shape of these parts (3D model) at the pre-production stage is obtained using modern methods of computed tomography and magnetic resonance imaging, and at the production stage the actual location of the stock grinding allowance is measured by laser (or tactile) scanning. To reduce the unevenness of the position of the grinding stock allowance, the workpiece of a complex-shaped part before grinding is oriented in the coordinate system of a CNC machine based on the established criterion for minimizing the allowance. An example of such orientation of the gear workpiece is given. This workpiece is measured with a Renishaw tactile probe on the left and right sides of the gear valleys before gear grinding. Both the minimum allowance on the left and right sides of the valleys and the difference between them are determined, and then additionally the gear wheel blank is rotated in the appropriate direction to align these minimum values detected. In turn, the aligned minimum allowances, should be sufficient to compensate for the influence of technological factors from the previous operation and the error in setting the workpiece for this operation. For complex-shaped implants, such an additional orientation is performed, for example, according to algorithms for ensuring the minimax value of the allowance.

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.


2021 ◽  
Vol 13 (3) ◽  
pp. 168781402110027
Author(s):  
Byung Chul Kim ◽  
Ilhwan Song ◽  
Duhwan Mun

Manufacturers of machine parts operate computerized numerical control (CNC) machine tools to produce parts precisely and accurately. They build computer-aided manufacturing (CAM) models using CAM software to generate code to control these machines from computer-aided design (CAD) models. However, creating a CAM model from CAD models is time-consuming, and is prone to errors because machining operations and their sequences are defined manually. To generate CAM models automatically, feature recognition methods have been studied for a long time. However, since the recognition range is limited, it is challenging to apply the feature recognition methods to parts having a complicated shape such as jet engine parts. Alternatively, this study proposes a practical method for the fast generation of a CAM model from CAD models using shape search. In the proposed method, when an operator selects one machining operation as a source machining operation, shapes having the same machining features are searched in the part, and the source machining operation is copied to the locations of the searched shapes. This is a semi-automatic method, but it can generate CAM models quickly and accurately when there are many identical shapes to be machined. In this study, we demonstrate the usefulness of the proposed method through experiments on an engine block and a jet engine compressor case.


2020 ◽  
Vol 6 (2) ◽  
pp. 029-033
Author(s):  
Herick Henci Agrisa

This paper discusses the pre and process of running a computer numerical control machine (CNC) using computer-aided design (CAD) software commonly used to design products to be produced and computer-aided manufacture (CAM) software used to control machines during the manufacturing process. Some types of CNC machines in general, namely CNC lathe machine and CNC milling machine. The history of the development of the CNC Machine was begun in 1952 by John Pearseon of the Massachusetts Institute of Technology on behalf of the United States Air Force, which aims to make complicated special workpieces. In addition, this paper also discusses the basic numerical code types used in CNC machines.


2021 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Berend Denkena ◽  
Marcel Wichmann ◽  
Klaas Maximilian Heide ◽  
René Räker

The automated process chain of an unmanned production system is a distinct challenge in the technical state of the art. In particular, accurate and fast raw-part recognition is a current problem in small-batch production. This publication proposes a method for automatic optical raw-part detection to generate a digital blank shadow, which is applied for adapted CAD/CAM (computer-aided design/computer-aided manufacturing) planning. Thereby, a laser-triangulation sensor is integrated into the machine tool. For an automatic raw-part detection and a workpiece origin definition, a dedicated algorithm for creating a digital blank shadow is introduced. The algorithm generates adaptive scan paths, merges laser lines and machine axis data, filters interference signals, and identifies part edges and surfaces according to a point cloud. Furthermore, a dedicated software system is introduced to investigate the created approach. This method is integrated into a CAD/CAM system, with customized software libraries for communication with the CNC (computer numerical control) machine. The results of this study show that the applied method can identify the positions, dimensions, and shapes of different raw parts autonomously, with deviations less than 1 mm, in 2.5 min. Moreover, the measurement and process data can be transferred without errors to different hardware and software systems. It was found that the proposed approach can be applied for rough raw-part detection, and in combination with a touch probe for accurate detection.


Author(s):  
Anthony Hotchkiss

Abstract At SUNY College at Buffalo, a new course, TEC302, CAD/CAM, computer-aided-design and computer-aided-manufacturing was added to the Industrial Technology (IT) undergraduate curriculum in the fall of 1994. At that time, the technology department had been using the AutoCAD system for design/drafting, and SmartCAM for demonstrating computer-aided-manufacturing. SmartCAM is a sophisticated product that takes a great deal of training to use, does not work directly in AutoCAD, and with only four licenses, was not available to all the students. For these reasons, the author developed a CAM program, VAL-CAM, that works inside AutoCAD, and has most of the aspects of a more sophisticated CAM program, yet is simpler to use, is available to all students, and automatically generates CNC (computer-numerical-control) code suitable for driving the departments’ vertical milling machining center. This paper discusses the development of VAL-CAM, which is written in the AutoLISP language for compatibility with AutoCAD. The dialogue control language (DCL) of AutoCAD was also used for part of the user interface for VALCAM. The algorithms, flow diagrams, pseudo code and actual LISP code for some of the more interesting parts of the program are presented. VAL-CAM is under continuous development, and later sections of the program will be discussed in future papers.


2014 ◽  
Vol 980 ◽  
pp. 184-188 ◽  
Author(s):  
Yusri Yusof ◽  
Kamran Latif

Computer Numerical Control (CNC) controller is an important part of machine, composed of hardware and software models. Software model, usually called an interpreter translates input code as per internal structure of CNC machine. Now a day’s traditional controllers of CNC machine are found to be closed in nature, because they are depended of vendor’s specifications. Due to that dependence they do not facilitate access to the inner features of machine. In order to overcome these problems open architecture controllers were introduced. In this article a new ISO 6983 translator for open architecture CNC controller is being proposed. The developed software model is able to read commercially available Computer Aided Design (CAD) /Computer Aided Manufacturing (CAM) system generated International Standards Organization (ISO) 6983 file and extracts position, feed rate, spindle speed, tool etc data and translates to OAC machine. At the same time it is also able to generate output in user defined text and EXtensible Markup Language (.xml) formats. Further design of paper includes development of translator, followed by case study experiment and finally ends with conclusion.


Author(s):  
A Mohole ◽  
P Wright ◽  
C Séquin

A key element in the overall efficiency of a manufacturing enterprise is the compatibility between the features that have been created in a newly designed part, and the capabilities of the downstream manufacturing processes. With this in mind, a process-aware computer aided design (CAD) system called WebCAD has been developed. The system restricts the freedom of the designer in such a way that the designed parts can be manufactured on a three-axis computer numerical control milling machine. This paper discusses the vision of WebCAD and explains the rationale for its development in comparison with commercial CAD/CAM (computer aided design/manufacture) systems. The paper then goes on to describe the implementation issues that enforce the manufacturability rules. Finally, certain design tools are described that aid a user during the design process. Some examples are given of the parts designed and manufactured with WebCAD.


Author(s):  
M. Minhat ◽  
X.W. Xu

Computer Numerical Control (CNC) systems are the “backbones” of modern manufacturing industry for over the last 50 years and the machine tools have evolved from simple machines with controllers that had no memory and were driven by punched tape, to today’s highly sophisticated, multiprocess workstations. These CNC systems are still being worked and improved on. The key issues center on autonomous planning, decision making, process monitoring and control systems that can adjust automatically to the changeable requirements. Introduction of CNC systems has made it possible to produce goods with consistent qualities, apart from enabling the industry to enhance productivity with a high degree of flexibility in a manufacturing system. CNC systems sit at the end of the process starting from product design using Computer Aided Design (CAD) tools to the generation of machining instructions that instruct a CNC machine to produce the final product. This process chain also includes Computer Aided Process Planning (CAPP) and Computer Aided Manufacturing (CAM).


Author(s):  
Xun Xu

Technologies concerning computer-aided design, process planning, manufacturing and numerical control, have matured to a point that commercialized software solutions and industrial systems can be acquired readily. These solutions or systems are, however, not necessarily connected in a seamless way, that is they are not fiintegrated. The term “islands of automation” has been used to describe these disconnected groups of systems with no obvious integration points other than the end user. As the engineering businesses are increasingly being run in a more globalized fashion, these islands of automation need to be connected to better suit and serve the collaborative and distributed environment. It is evident that the businesses are struggling with this integration strategy at a number of levels other than the underlying technology, including CAD, CAPP, CAM, and CNC for example. In some cases, where integration does not exist among these computer-aided solutions, promising product technologies may come to a sudden halt against these barriers. The previous chapters have focused on these individual computer-aided solutions, e.g. CAD, CAPP, CAM, CNC, and feature technologies. Some localized integration such as integrated feature technology has been studied. The following chapters, will in particular, look at the integration issues, technologies, and solutions. This chapter starts with a general description of traditional CAD, CAPP, CAM, and CNC integration models. This is followed by an industry case study showcasing how a proprietary CAD/CAM can be used to achieve centralized integration. To illustrate CAM/CNC integration, three different efforts are mentioned. They are APT, BCL (Binary Cutter Location, (EIA/ANSI, 1992)), BNCL (Base Numerical Control Language, (Fortin, Chatelain & Rivest, 2004)) and use of Haskell language for CNC programming (Arroyo, Ochoa, Silva & Vidal, 2004).


2014 ◽  
Vol 40 (5) ◽  
pp. 561-569 ◽  
Author(s):  
Francesco Mangano ◽  
Aldo Macchi ◽  
Jamil Awad Shibli ◽  
Giuseppe Luongo ◽  
Giovanna Iezzi ◽  
...  

Several procedures have been proposed to achieve maxillary ridge augmentation. These require bone replacement materials to be manually cut, shaped, and formed at the time of implantation, resulting in an expensive and time-consuming process. In the present study, we describe a technique for the design and fabrication of custom-made scaffolds for maxillary ridge augmentation, using three-dimensional computerized tomography (3D CT) and computer-aided design/computer-aided manufacturing (CAD/CAM). CT images of the atrophic maxillary ridge of 10 patients were acquired and modified into 3D reconstruction models. These models were transferred as stereolithographic files to a CAD program, where a virtual 3D reconstruction of the alveolar ridge was generated, producing anatomically shaped, custom-made scaffolds. CAM software generated a set of tool-paths for manufacture by a computer-numerical-control milling machine into the exact shape of the reconstruction, starting from porous hydroxyapatite blocks. The custom-made scaffolds were of satisfactory size, shape, and appearance; they matched the defect area, suited the surgeon's requirements, and were easily implanted during surgery. This helped reduce the time for surgery and contributed to the good healing of the defects.


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