Efficient NC Simulation for Multi-Axis Solid Machining With a Universal APT Cutter

2009 ◽  
Vol 9 (2) ◽  
Author(s):  
Hong-Tzong Yau ◽  
Lee-Sen Tsou
Keyword(s):  
Computer Aided Design ◽  
Numerical Control ◽  
Tool Geometry ◽  
Algebraic Equations ◽  
Sculptured Surfaces ◽  
Simulation Accuracy ◽  
Nc Simulation ◽  
Marching Cube Algorithm ◽  
Voxel Representation ◽  
Five Axis

In multi-axis machining of dies and molds with complex sculptured surfaces, numerical control (NC) simulation/verification is a must for the avoidance of expensive rework and material waste. Despite the fact that NC simulation has been extensively used by industries for many years, efficient, accurate, and reliable view-independent simulation of multi-axis NC machining still remains a difficult challenge. This paper presents the use of adaptive voxel data structure in conjunction with the modeling of a universal cutter for the development of an efficient and reliable multi-axis (typically five-axis) simulation procedure. The octree-based voxel representation of the workpiece saves a significant amount of memory space without sacrificing the simulation accuracy. Rendering of the voxel-based model is view independent and does not suffer from any aliasing effect, due to the real-time triangulation of the boundary surfaces using an extended marching cube algorithm. Implicit algebraic equations are used to model the automatically programed tool geometry, which can represent a universal cutter with high precision. In addition, the proposed method allows users to perform error analysis and gouging detection by comparing the machined surfaces with the original computer-aided design (CAD) model. Illustration of the implementation and experimental results demonstrate that the proposed method is reliable, accurate, and highly efficient.

Computation of Optimal Workpiece Orientation for Multi-axis NC Machining of Sculptured Part Surfaces

2002 ◽  
Vol 124 (2) ◽  
pp. 201-212 ◽  
Author(s):  
Stephen P. Radzevich ◽  
Erik D. Goodman
Keyword(s):  
Cutting Tool ◽  
Nc Machining ◽  
Numerical Control ◽  
Tool Geometry ◽  
Geometric Problem ◽  
Part Surface ◽  
Nc Machine ◽  
New Type ◽  
Five Axis ◽  
Workpiece Orientation

Optimal workpiece orientation for multi-axis sculptured part surface machining is generally defined as orientation of the workpiece so as to minimize the number of setups in 4-, 5- or more axis Numerical Control (NC) machining, or to allow the maximal number of surfaces to be machined in a single setup on a three-, four-, or five-axis NC machine. This paper presents a method for computing such an optimal workpiece orientation based on the geometry of the part surface to be machined, of the machining surface of the tool, and of the degrees of freedom available on the multi-axis NC machine. However, for cases in which some freedom of orientation remains after conditions for machining in a single setup are satisfied, a second sort of optimality can also be considered: finding an orientation such that the cutting condition (relative orientation of the tool axis and the normal to the desired part surface) remains as constant, at some optimal angle, as possible. This second form of optimality is obtained by choosing an orientation (within the bounds of those allowing a single setup) in which the angle between the neutral axis of the milling tool and the area-weighted mean normal to the part surface, at a “central” point with a normal in that mean direction, is zero, or as small as possible. To find this solution, Gaussian maps (GMap) of the part surfaces to be machined and the machining surface of the tool are applied. To our knowledge, we are the first [1] who have picked up this Gauss’ idea to sculptured part surface orientation problem and who have developed the general approach to solve this important engineering problem [2]. Later a similar approach was claimed by Gan [3]. By means of GMaps of these surfaces, the problem of optimal workpiece orientation can be formulated as a geometric problem on a sphere. The GMap on a unit sphere finds wide application for orientation of workpiece for NC machining, for probing on coordinate measuring machines, etc. GMaps are useful for selecting the type of cutting tool, its path, workpiece fixturing, and the type of NC machine (its kinematic capabilities). The primary process application addressed is 3- and 4-axis NC milling, although the techniques presented may be applied to machines with more general articulation. The influence of tool geometry is also discussed and incorporated within a constrained orientation algorithm. This paper covers the following topics: a) the derivation of the equations of the GMap of the part surface to be machined and the machining surface of the tool; b) calculation of the parameters of the weighted normal to the part surface; c) optimal part orientation on the table of a multi-axis NC machine; d) introduction of a new type of GMap for a sculptured part surface—its expandedGMapE; and e) introduction of a new type of indicatrix of a sculptured part surface and a particular cutting tool–the indicatrix of machinability.

Five-Axis Swept Volumes for Graphic NC Simulation and Verification

1989 ◽  
Author(s):  
K. Sambandan ◽  
K. K. Wang
Keyword(s):  
Nc Machining ◽  
Image Space ◽  
Numerical Control ◽  
Mathematical Basis ◽  
Nc Simulation ◽  
Swept Volumes ◽  
Nc Milling ◽  
Depth Buffer ◽  
Swept Volume ◽  
Five Axis

Abstract This paper explains in detail a simulator that has been developed for graphic verification of five-axis Numerical Control (NC) machining. Exact parametric representations for the surfaces generated by common NC milling cutters during five-axis motions have been derived using the theory of envelopes as the mathematical basis. Parts of these surfaces form the boundary of the total swept volume generated. For each cutting motion, the swept volume of the cutter is determined and then subtracted from the stock. The Boolean subtraction is done in the image space at the pixel level, using a modified depth-buffer algorithm. A shaded image of the “as machined” part at the end of each cutting motion is then displayed for verification.

An Approach to the Low-Cost Computer Aided Manufacture of Components Embodying Free-Form Surfaces

1989 ◽  
Vol 203 (2) ◽  
pp. 119-126 ◽  
Author(s):  
X Gao ◽  
D K Harrison ◽  
B J Davies
Keyword(s):  
Computer Aided Design ◽  
Numerical Control ◽  
Personal Computers ◽  
Surface Patch ◽  
Free Form ◽  
Height Determination ◽  
Computer Aided ◽  
Cusp Height ◽  
Five Axis ◽  
Free Form Surfaces

The numerical control (NC) machining of free-form surfaces is usually accomplished utilizing minicomputer or mainframe computer aided design and manufacturing (C ADC AM) systems. The resulting NC data are suitable for either three-axis or five-axis machining dependent upon machine tool type/capability and CAM package complexity. However, the cost of such packages and systems precludes the use of these in smaller companies with an occasional requirement for components embodying free-form surfaces. The increasing availability of powerful yet reasonably priced personal computers (PC) coupled with improving software provides such companies with a far cheaper alternative approach. However, a common feature of PC-based CADCAM systems is that they are limited to 2 1/2-axis machining for all but special applications such as three-axis canted Z-plane milling of four-axis wire electro discharge machining (EDM). This paper presents a method for manufacturing true three-dimensional free-form surfaces using PC-based 2 1/2-axis CADCAM systems. All the main functions performed on mainframe systems can be performed on personal computers, such as toolpath generation for free-form surfaces, cusp height determination and change in shape and volume which may be used for the compensation of shrinkage or to suit market requirements. This is significant for manufacturers who make use of moulds, such as are found in the plastic processing industries. The manufacture of a blown plastic bottle mould is presented as a typical example. The inclusion into the PC environment of features to be found in mainframe systems is also discussed, such as machining the surface patch by patch in any direction or machining a number of patches at one time, shape and volume change in any direction, cusp height determination, etc.

Surface Reconstruction Using Dexel Data From Three Sets of Orthogonal Rays

2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Weihan Zhang ◽  
Ming C. Leu
Keyword(s):  
Surface Reconstruction ◽  
Boundary Surface ◽  
Numerical Control ◽  
Surface Model ◽  
Reconstruction Method ◽  
Virtual Sculpting ◽  
Marching Cube Algorithm ◽  
Voxel Representation ◽  
Reconstructed Surface ◽  
Representation Method

Triple-dexel modeling is a geometric representation method, which depicts the intersection of a solid with rays cast in three orthogonal directions. Due to its fast Boolean operations, simple data structure, and easy implementation, triple-dexel modeling is highly suitable for real-time graphics-based simulation applications such as numerical control (NC) machining verification and virtual sculpting. This paper presents a novel surface reconstruction method from triple-dexel data by first converting the triple-dexel data into contours on three sets of orthogonal slices and then generating the solid’s boundary surface in triangular facets from these contours. The developed method is faster than the voxel-based method, and the reconstructed surface model is more accurate than the surface reconstructed from voxel representation using the marching cube algorithm. Examples are given to demonstrate the ability of surface reconstruction from the triple-dexel model in virtual sculpting.

Five-Axis-Grinding With Toric Tools: A Status Review

2012 ◽  
Vol 134 (5) ◽  
Author(s):  
Berend Denkena ◽  
Anke Turger ◽  
Leif Behrens ◽  
Thomas Krawczyk
Keyword(s):  
Computer Aided Design ◽  
Tool Path ◽  
Free Form ◽  
Aviation Industry ◽  
Tool Geometry ◽  
Curved Surfaces ◽  
Shape Accuracy ◽  
Computer Aided ◽  
Five Axis ◽  
Free Form Surfaces

Free form surfaces are used in various applications, such as in the aviation industry, in the medicine, or for tool and die making. Compressor blades as well as knee prostheses and dies have complex curved surfaces. Five-axis grinding is a possibility to machine such curved surfaces in a high shape accuracy and surface quality. The use of this technology depends on a high degree of the operational background. Furthermore, the complexity of the tool path generation requires the use of computer-aided design/computer aided manufacturing (CAD/CAM) systems. This technical review gives an overview about state of the art of five-axis grinding and presents results, which can close some scientific lacks. Models were developed to predict the surface roughness and material removal dependent on the process parameters. Additionally, the relationship between tool geometry, shape accuracy as well as contact conditions is discussed.

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.

scholarly journals Development of a numerical compensation framework for geometrical deviations in bulk metal forming exploiting a surrogate model and computed compatible stresses

2021 ◽  
Author(s):  
Lorenzo Scandola ◽  
Christoph Büdenbender ◽  
Michael Till ◽  
Daniel Maier ◽  
Michael Ott ◽  
...  
Keyword(s):  
Finite Element ◽  
Surrogate Model ◽  
Metal Forming ◽  
Computer Aided Design ◽  
Transition Process ◽  
Reference Points ◽  
Compensation Method ◽  
Tool Geometry ◽  
Bulk Metal ◽  
Bulk Metal Forming

AbstractThe optimal design of the tools in bulk metal forming is a crucial task in the early design phase and greatly affects the final accuracy of the parts. The process of tool geometry assessment is resource- and time-consuming, as it consists of experience-based procedures. In this paper, a compensation method is developed with the aim to reduce geometrical deviations in hot forged parts. In order to simplify the transition process between the discrete finite-element (FE) mesh and the computer-aided-design (CAD) geometry, a strategy featuring an equivalent surrogate model is proposed. The deviations are evaluated on a reduced set of reference points on the nominal geometry and transferred to the FE nodes. The compensation approach represents a modification of the displacement-compatible spring-forward method (DC-SF), which consists of two elastic FE analyses. The compatible stress originating the deviations is estimated and subsequently applied to the original nominal geometry. After stress relaxation, an updated nominal geometry of the part is obtained, whose surfaces represent the compensated tools. The compensation method is verified by means of finite element simulations and the robustness of the algorithm is demonstrated with an additional test geometry. Finally, the compensation strategy is validated experimentally.

scholarly journals Study of Machining of Gears with Regular and Modified Outline Using CNC Machine Tools

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2913
Author(s):  
Rafał Gołębski ◽  
Piotr Boral
Keyword(s):  
Machine Tools ◽  
Coordinate Measuring Machine ◽  
Optical Microscope ◽  
Numerical Control ◽  
Cnc Machine Tools ◽  
Cnc Milling ◽  
Cnc Machine ◽  
Cylindrical Gears ◽  
Measuring Machine ◽  
Five Axis

Classic methods of machining cylindrical gears, such as hobbing or circumferential chiseling, require the use of expensive special machine tools and dedicated tools, which makes production unprofitable, especially in small and medium series. Today, special attention is paid to the technology of making gears using universal CNC (computer numerical control) machine tools with standard cheap tools. On the basis of the presented mathematical model, a software was developed to generate a code that controls a machine tool for machining cylindrical gears with straight and modified tooth line using the multipass method. Made of steel 16MnCr5, gear wheels with a straight tooth line and with a longitudinally modified convex-convex tooth line were machined on a five-axis CNC milling machine DMG MORI CMX50U, using solid carbide milling cutters (cylindrical and ball end) for processing. The manufactured gears were inspected on a ZEISS coordinate measuring machine, using the software Gear Pro Involute. The conformity of the outline, the tooth line, and the gear pitch were assessed. The side surfaces of the teeth after machining according to the planned strategy were also assessed; the tests were carried out using the optical microscope Alicona Infinite Focus G5 and the contact profilographometer Taylor Hobson, Talysurf 120. The presented method is able to provide a very good quality of machined gears in relation to competing methods. The great advantage of this method is the use of a tool that is not geometrically related to the shape of the machined gear profile, which allows the production of cylindrical gears with a tooth and profile line other than the standard.

scholarly journals Practical method for the fast generation of a CAM model for jet engine parts

2021 ◽  
Vol 13 (3) ◽  
pp. 168781402110027
Author(s):  
Byung Chul Kim ◽  
Ilhwan Song ◽  
Duhwan Mun
Keyword(s):  
Computer Aided Design ◽  
Feature Recognition ◽  
Practical Method ◽  
Numerical Control ◽  
Cnc Machine Tools ◽  
Cnc Machine ◽  
Jet Engine ◽  
Computer Aided ◽  
Cad Models ◽  
Cam Model

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.

scholarly journals Computer-aided design of multi-purpose steel headframes for mines with a new technical level

2020 ◽  
Vol 174 ◽  
pp. 01048
Author(s):  
Elena Kassikhina ◽  
Vladimir Pershin ◽  
Nina Rusakova
Keyword(s):  
Cross Sections ◽  
Computer Aided Design ◽  
Information Technologies ◽  
Three Dimensional ◽  
Numerical Control ◽  
Technical Level ◽  
Resource Saving ◽  
Existing Structures ◽  
Set Up ◽  
Aided Design

The existing structures of the steel sinking headgear and permanent headframe do not meet the requirements of resource saving (metal consumption and manpower input at installation), and the present methods of the headframe designing do not fully reflect recent possibilities of applying of the advanced information technologies. Technical level of the modern software makes it possible for designers to set up multiple numerical experiments to create a computer simulation that allows solving the problem without field and laboratory experiments, and therefore without special costs. In this regard, a mathematical simulation has been developed and based on it, software to select cross-sections of multi- purpose steel headframe elements and to calculate proper weight of its metal structures depending on the characteristics and hoisting equipment. A headframe drawing is displayed, as the results of the software work, including list of elements, obtained optimal hoisting equipment in accordance with the initial data. The software allows speeding up graphic work and reducing manpower input on calculations and paper work. The software allows developing a three-dimensional image of the structure and its functional blocks, based on the obtained initial parameters, as well as developing control software for units with numerical control (NC) in order to manufacture multi-purpose headframes.

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