scholarly journals Laser Scanning Based Object Detection to Realize Digital Blank Shadows for Autonomous Process Planning in Machining

2021 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Berend Denkena ◽  
Marcel Wichmann ◽  
Klaas Maximilian Heide ◽  
René Räker
Keyword(s):  
Computer Aided Design ◽  
Laser Scanning ◽  
Numerical Control ◽  
Software Systems ◽  
Process Data ◽  
Computer Aided ◽  
Cad Cam ◽  
Scan Paths ◽  
Interference Signals ◽  
Aided Design

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.

scholarly journals Evaluation of the Feasibility of NaCaPO4-Blended Zirconia as a New CAD/CAM Material for Dental Restoration

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3819
Author(s):  
Ting-Hsun Lan ◽  
Yu-Feng Chen ◽  
Yen-Yun Wang ◽  
Mitch M. C. Chou
Keyword(s):  
Computer Aided Design ◽  
Optical Microscope ◽  
Dental Restoration ◽  
Numerical Control ◽  
Test Results ◽  
Cnc Machine ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design ◽  
Better Than

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.

The Development of a Profile-Milling Program for Teaching Computer-Aided-Manufacturing and CNC Programming

1997 ◽  
Author(s):  
Anthony Hotchkiss
Keyword(s):  
Computer Aided Design ◽  
Undergraduate Curriculum ◽  
Numerical Control ◽  
Computer Aided Manufacturing ◽  
Machining Center ◽  
Vertical Milling ◽  
Computer Aided ◽  
Cad Cam ◽  
Cnc Programming ◽  
Aided Design

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.

WebCAD: A computer aided design tool constrained with explicit ‘design for manufacturability’ rules for computer numerical control milling

2002 ◽  
Vol 216 (6) ◽  
pp. 879-889 ◽  
Author(s):  
A Mohole ◽  
P Wright ◽  
C Séquin
Keyword(s):  
Computer Aided Design ◽  
Computer Numerical Control ◽  
Design Tool ◽  
Numerical Control ◽  
Milling Machine ◽  
Design Tools ◽  
Cad System ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

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.

Integration of CAD/CAPP/CAM/CNC

2009 ◽  
pp. 231-245 ◽  
Author(s):  
Xun Xu
Keyword(s):  
Computer Aided Design ◽  
Numerical Control ◽  
General Description ◽  
Distributed Environment ◽  
Industrial Systems ◽  
Integration Strategy ◽  
Computer Aided ◽  
Cad Cam ◽  
Cnc Programming ◽  
Aided Design

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).

scholarly journals Maxillary Ridge Augmentation with Custom-Made CAD/CAM Scaffolds. A 1-Year Prospective Study on 10 Patients

2014 ◽  
Vol 40 (5) ◽  
pp. 561-569 ◽  
Author(s):  
Francesco Mangano ◽  
Aldo Macchi ◽  
Jamil Awad Shibli ◽  
Giuseppe Luongo ◽  
Giovanna Iezzi ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Computer Aided Design ◽  
Three Dimensional ◽  
Numerical Control ◽  
Porous Hydroxyapatite ◽  
Ridge Augmentation ◽  
Custom Made ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

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.

scholarly journals Custom-Made Computer-Aided-Design/Computer-Aided-Manufacturing Biphasic Calcium-Phosphate Scaffold for Augmentation of an Atrophic Mandibular Anterior Ridge

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Francesco Guido Mangano ◽  
Piero Antonio Zecca ◽  
Ric van Noort ◽  
Samvel Apresyan ◽  
Giovanna Iezzi ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Computer Aided Design ◽  
Biphasic Calcium Phosphate ◽  
Numerical Control ◽  
Ridge Augmentation ◽  
Custom Made ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design ◽  
Anterior Mandible

This report documents the clinical, radiographic, and histologic outcome of a custom-made computer-aided-design/computer-aided-manufactured (CAD/CAM) scaffold used for the alveolar ridge augmentation of a severely atrophic anterior mandible. Computed tomographic (CT) images of an atrophic anterior mandible were acquired and modified into a 3-dimensional (3D) reconstruction model; this was transferred to a CAD program, where a custom-made scaffold was designed. CAM software generated a set of tool-paths for the manufacture of the scaffold on a computer-numerical-control milling machine into the exact shape of the 3D design. A custom-made scaffold was milled from a synthetic micromacroporous biphasic calcium phosphate (BCP) block. The scaffold closely matched the shape of the defect: this helped to reduce the time for the surgery and contributed to good healing. One year later, newly formed and well-integrated bone was clinically available, and two implants (AnyRidge, MegaGen, Gyeongbuk, South Korea) were placed. The histologic samples retrieved from the implant sites revealed compact mature bone undergoing remodelling, marrow spaces, and newly formed trabecular bone surrounded by residual BCP particles. This study demonstrates that custom-made scaffolds can be fabricated by combining CT scans and CAD/CAM techniques. Further studies on a larger sample of patients are needed to confirm these results.

Research and Development of CNC Cool Frame Bender

2008 ◽  
Vol 24 (01) ◽  
pp. 7-11
Author(s):  
Pei-yong Li ◽  
Chengfang Wang ◽  
Yunsheng Mao ◽  
Yong Hu ◽  
Yongqing Zhou
Keyword(s):  
Computer Aided Design ◽  
Production Efficiency ◽  
Plane Deformation ◽  
Cost Savings ◽  
Numerical Control ◽  
Computer Aided ◽  
Out Of Plane ◽  
Cad Cam ◽  
New Type ◽  
Aided Design

A new type of ship's frame bender with computer numerical control (CNC) has been developed and installed in many shipyards. The bender has many advantages and will result in significant cost savings and increased production efficiency. The CNC bender is compatible with existing shipyard automation programs, using the frame data generated by a computer-aided design/computer-aided manufacturing (CAD/ CAM) system to produce a formed frame automatically. The bender can straighten deformed beams in both horizontal and vertical planes, as well as bend them in the horizontal plane without out-of-plane deformation. Markings can be stamped at the required position in the bending process.

Structural Analysis of Product and Computer-Aided Assembly Planning in AssemBL Software Package

2018 ◽  
pp. 11-33
Author(s):  
A. N. Bozhko
Keyword(s):  
Computer Aided Design ◽  
State Of The Art ◽  
Graph Model ◽  
Design System ◽  
Assembly Planning ◽  
Complex Products ◽  
Assembly Sequences ◽  
Computer Aided ◽  
Cad Cam ◽  
Aided Design

Computer-aided design of assembly processes (Computer aided assembly planning, CAAP) of complex products is an important and urgent problem of state-of-the-art information technologies. Intensive research on CAAP has been underway since the 1980s. Meanwhile, specialized design systems were created to provide synthesis of assembly plans and product decompositions into assembly units. Such systems as ASPE, RAPID, XAP / 1, FLAPS, Archimedes, PRELEIDES, HAP, etc. can be given, as an example. These experimental developments did not get widespread use in industry, since they are based on the models of products with limited adequacy and require an expert’s active involvement in preparing initial information. The design tools for the state-of-the-art full-featured CAD/CAM systems (Siemens NX, Dassault CATIA and PTC Creo Elements / Pro), which are designed to provide CAAP, mainly take into account the geometric constraints that the design imposes on design solutions. These systems often synthesize technologically incorrect assembly sequences in which known technological heuristics are violated, for example orderliness in accuracy, consistency with the system of dimension chains, etc.An AssemBL software application package has been developed for a structured analysis of products and a synthesis of assembly plans and decompositions. The AssemBL uses a hyper-graph model of a product that correctly describes coherent and sequential assembly operations and processes. In terms of the hyper-graph model, an assembly operation is described as shrinkage of edge, an assembly plan is a sequence of shrinkages that converts a hyper-graph into the point, and a decomposition of product into assembly units is a hyper-graph partition into sub-graphs.The AssemBL solves the problem of minimizing the number of direct checks for geometric solvability when assembling complex products. This task is posed as a plus-sum two-person game of bicoloured brushing of an ordered set. In the paradigm of this model, the brushing operation is to check a certain structured fragment for solvability by collision detection methods. A rational brushing strategy minimizes the number of such checks.The package is integrated into the Siemens NX 10.0 computer-aided design system. This solution allowed us to combine specialized AssemBL tools with a developed toolkit of one of the most powerful and popular integrated CAD/CAM /CAE systems.

scholarly journals Characterisation of the Filler Fraction in CAD/CAM Resin-Based Composites

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1986
Author(s):  
Andreas Koenig ◽  
Julius Schmidtke ◽  
Leonie Schmohl ◽  
Sibylle Schneider-Feyrer ◽  
Martin Rosentritt ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Point Of View ◽  
Specific Information ◽  
Dental Resin ◽  
X Ray ◽  
Computer Aided ◽  
Cad Cam ◽  
Filler Fraction ◽  
The Individual ◽  
Aided Design

The performance of dental resin-based composites (RBCs) heavily depends on the characteristic properties of the individual filler fraction. As specific information regarding the properties of the filler fraction is often missing, the current study aims to characterize the filler fractions of several contemporary computer-aided design/computer-aided manufacturing (CAD/CAM) RBCs from a material science point of view. The filler fractions of seven commercially available CAD/CAM RBCs featuring different translucency variants were analysed using Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS), Micro-X-ray Computed Tomography (µXCT), Thermogravimetric Analysis (TG) and X-ray Diffractometry (XRD). All CAD/CAM RBCs investigated included midifill hybrid type filler fractions, and the size of the individual particles was clearly larger than the individual specifications of the manufacturer. The fillers in Shofu Block HC featured a sphericity of ≈0.8, while it was <0.7 in all other RBCs. All RBCs featured only X-ray amorphous phases. However, in Lava Ultimate, zircon crystals with low crystallinity were detected. In some CAD/CAM RBCs, inhomogeneities (X-ray opaque fillers or pores) with a size <80 µm were identified, but the effects were minor in relation to the total volume (<0.01 vol.%). The characteristic parameters of the filler fraction in RBCs are essential for the interpretation of the individual material’s mechanical and optical properties.

scholarly journals Influence of Sequential CAD/CAM Milling on the Fitting Accuracy of Titanium Three-Unit Fixed Dental Prostheses

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1401
Author(s):  
Doo-Bin Song ◽  
Man-So Han ◽  
Si-Chul Kim ◽  
Junyong Ahn ◽  
Yong-Woon Im ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Computer Aided Design ◽  
Dental Prostheses ◽  
Computer Aided ◽  
Cad Cam ◽  
Fixed Dental Prostheses ◽  
Gap Data ◽  
Aided Design ◽  
Fitting Accuracy

This study investigated the fitting accuracy of titanium alloy fixed dental prostheses (FDP) after sequential CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) fabrication. A three-unit FDP model connecting mandibular second premolars and molars was prepared and scanned to fabricate titanium FDPs by CAD/CAM milling. A total of six FDPs were sequentially milled in one titanium alloy disk using a new set of burs every time (n = 4). The fitting accuracy of FDPs was mesiodistally evaluated by a silicone replica technique and the measurement was triplicated at four different locations: MO (marginal opening), MG (marginal gap), AG (axial gap), and OG (occlusal gap). Data were statistically analyzed using ANOVA and Tukey’s HSD test. The fitting accuracy of PMMA (polymethyl methacrylate) FDPs milled using the worn or new bur were evaluated by the same procedure (n = 6). The mean dimensions of titanium FDP for all measuring positions, except for AG, were significantly increased from the third milling. However, no difference was noted between the first FDP and the second FDP milled with the same set of burs. Severe edge chippings were observed in all milling burs. Detrimental effects of the worn burs on the fitting accuracy were demonstrated in the CAD/CAM-milled PMMA FDP. The results recommend proper changing frequency of cutting burs to achieve the quality of fit and predictable outcomes for dental CAD/CAM prostheses.

Sign in / Sign up

Export Citation Format

Share Document