A Solid Modeler Approach for Extracting Cutter Workpiece Engagements in Milling

2008 ◽  
Author(s):  
Eyyup Aras ◽  
Derek Yip-Hoi
Keyword(s):  
Geometric Modeling ◽  
Cutting Tools ◽  
Free Form ◽  
Tool Geometry ◽  
Depth Of Cut ◽  
Modeling Methodology ◽  
Engagement Angle ◽  
Solid Modeler ◽  
Free Form Surfaces ◽  
Boundary Curves

This paper presents a Solid modeling methodology for finding Cutter Workpiece Engagements (CWEs) generated during 3+2 -axis machining (spindle can tilt) of free – form surfaces using a range of different types of cutting tools and tool paths. Swept volumes of the cutters are generated utilizing the envelope theory. For the CWE extractions the removal volumes of the cutter constituent surfaces are used. For this purpose the cutter surfaces are decomposed with respect to the tool feed direction and then they intersected with their removal volumes for obtaining the boundary curves of the closed CWE area. The CWE boundary curves are mapped from Euclidean space to a parametric space defined by the engagement angle and the depth-of-cut for a given tool geometry. The reported method has been implemented using a commercial geometric modeler (ACIS) which is selected to be the kernel around which the geometric simulator is built. The described geometric methodology is being developed as part of a Virtual Milling methodology that combines the geometric modeling aspects of milling material removal with the modeling of the process.

Tool Contact Maps by Rectangular Grid Decomposition

2011 ◽  
Author(s):  
Eyyup Aras
Keyword(s):  
Geometric Modeling ◽  
Free Form ◽  
Tool Geometry ◽  
Depth Of Cut ◽  
Force Model ◽  
Rectangular Grid ◽  
Ongoing Research ◽  
Circle Plane ◽  
Milling Operations ◽  
Free Form Surfaces

This paper is intended to contribute to ongoing research [1–3] in geometric modeling of the virtual machining. In geometric modeling the tool paths are verified by performing the machining simulations and also the cutter workpiece engagements (CWEs) are extracted. CWE geometry is a key input to force calculations and feed rate scheduling in milling operations. Finding these engagements is challenging due to the complicated and changing intersection geometry between the cutter and the in-process workpiece. This paper presents a discrete model based methodology for extracting CWEs generated during a multi axis machining of free form surfaces using a range of different types of milling tools. In this method the in-process workpiece is represented by a set of z-axis aligned rectangular grids. Each grid is made up of four planes, with their normals aligned with respect to the x and y-axis of the Cartesian coordinate system. In developing the methodology the parametric representations of the automatically programmed tool (APT)-type milling cutters are used. The milling tool surfaces are decomposed into circles. During the material removal process only some portions of those circles which are called the engagement arcs may contact the in-process workpiece. To find the geometric limits of those arcs the concept of the feasible contact surface is utilized. The CWE extraction simulation is performed through intersecting those arcs with the planes of each rectangular grid. Thus the intersection calculations reduce to circle/plane intersections which can be performed analytically for the geometry found on milling cutters. To be used in the force model, the CWE boundaries are mapped from Euclidean 3D space to a parametric space defined by the engagement angle and the depth-of-cut for a given tool geometry. Then using a sort algorithm the neighboring engagements in the same arc level are combined.

Geometric Modeling of Cutter/Workpiece Engagements in 3-Axis Milling Using Polyhedral Models

2007 ◽  
Author(s):  
Eyyup Aras ◽  
Derek Yip-Hoi
Keyword(s):  
Cutting Forces ◽  
Geometric Modeling ◽  
Tool Path ◽  
Cutting Tool ◽  
Milling Process ◽  
Mapping Technique ◽  
Depth Of Cut ◽  
Modeling Methodology ◽  
Machining System ◽  
Engagement Angle

Modeling the milling process requires cutter/workpiece engagement (CWE) geometry in order to predict cutting forces. The calculation of these engagements is challenging due to the complicated and changing intersection geometry that occurs between the cutter and the in-process workpiece. This geometry defines the instantaneous intersection boundary between the cutting tool and the in-process workpiece at each location along a tool path. This paper presents components of a robust and efficient geometric modeling methodology for finding CWEs generated during 3-axis machining of surfaces using a range of different types of cutting tool geometries. A mapping technique has been developed that transforms a polyhedral model of the removal volume from Euclidean space to a parametric space defined by location along the tool path, engagement angle and the depth-of-cut. As a result, intersection operations are reduced to first order plane-plane intersections. This approach reduces the complexity of the cutter/workpiece intersections and also eliminates robustness problems found in standard polyhedral modeling and improves accuracy over the Z-buffer technique. The CWEs extracted from this method are used as input to a force prediction model that determines the cutting forces experienced during the milling operation. The reported method has been implemented and tested using a combination of commercial applications. This paper highlights ongoing collaborative research into developing a Virtual Machining System.

Geometric Modeling and Analysis of Single Point Cutting Tools With Generic Profile

2011 ◽  
Author(s):  
Kumar Sambhav ◽  
Puneet Tandon ◽  
Sanjay G. Dhande
Keyword(s):  
Geometric Modeling ◽  
Geometric Model ◽  
Single Point ◽  
Cutting Tools ◽  
Free Form ◽  
Generic Model ◽  
Modeling And Analysis ◽  
Grinding Parameters ◽  
Two Generations ◽  
Free Form Surfaces

The presented work models the geometry of Single Point Cutting Tools (SPCTs) with generic profile. Presently few standard shapes of SPCTs defined in terms of projective geometry are being employed while there is a need to design free-form tools to efficiently machine free-form surfaces with few passes and chosen range of cutting angles. To be able to produce SPCT face and flanks with generic shapes through grinding, a comprehensive geometric model of the tool in terms of the varying grinding angles and the ground depths is required which helps design the tool with arbitrarily chosen tool angles. The surface modeling begins with the creation of a tool blank model followed by transformation of unbounded planes to get the cutting tool surfaces. The intersection of these surfaces with the blank gives the complete model of the tool. Having created the geometric model in two generations of generalization, the paper presents the methodology to obtain the conventional tool angles from the generic model. An illustration of the model has been provided showing variation of tool angles along the cutting edge with changing grinding parameters. When the geometric model is not to be related to the grinding parameters, the SPCT can be modeled as a composite NURBS surface which has been presented towards the end of the work.

Geometric Modeling of Cutter/Workpiece Engagements in Three-Axis Milling Using Polyhedral Representations

2008 ◽  
Vol 8 (3) ◽  
Author(s):  
Eyyup Aras ◽  
Derek Yip-Hoi
Keyword(s):  
Cutting Forces ◽  
Geometric Modeling ◽  
Tool Path ◽  
Cutting Tool ◽  
Milling Process ◽  
Mapping Technique ◽  
Depth Of Cut ◽  
Modeling Methodology ◽  
Machining System ◽  
Engagement Angle

Modeling the milling process requires cutter/workpiece engagement (CWE) geometry in order to predict cutting forces. The calculation of these engagements is challenging due to the complicated and changing intersection geometry that occurs between the cutter and the in-process workpiece. This geometry defines the instantaneous intersection boundary between the cutting tool and the in-process workpiece at each location along a tool path. This paper presents components of a robust and efficient geometric modeling methodology for finding CWEs generated during three-axis machining of surfaces using a range of different types of cutting tool geometries. A mapping technique has been developed that transforms a polyhedral model of the removal volume from the Euclidean space to a parametric space defined by the location along the tool path, the engagement angle, and the depth of cut. As a result, intersection operations are reduced to first order plane-plane intersections. This approach reduces the complexity of the cutter/workpiece intersections and also eliminates robustness problems found in standard polyhedral modeling and improves accuracy over the Z-buffer technique. The CWEs extracted from this method are used as input to a force prediction model that determines the cutting forces experienced during the milling operation. The reported method has been implemented and tested using a combination of commercial applications. This paper highlights ongoing collaborative research into developing a virtual machining system.

scholarly journals Construction and analysis of unified 4-point interpolating nonstationary subdivision surfaces

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Mehwish Bari ◽  
Ghulam Mustafa ◽  
Abdul Ghaffar ◽  
Kottakkaran Sooppy Nisar ◽  
Dumitru Baleanu
Keyword(s):  
Computer Graphics ◽  
Geometric Modeling ◽  
Tension Control ◽  
Free Form ◽  
Subdivision Surfaces ◽  
Smooth Curves ◽  
Practical Applications ◽  
Tension Parameter ◽  
Exact Reproduction ◽  
Free Form Surfaces

AbstractSubdivision schemes (SSs) have been the heart of computer-aided geometric design almost from its origin, and several unifications of SSs have been established. SSs are commonly used in computer graphics, and several ways were discovered to connect smooth curves/surfaces generated by SSs to applied geometry. To construct the link between nonstationary SSs and applied geometry, in this paper, we unify the interpolating nonstationary subdivision scheme (INSS) with a tension control parameter, which is considered as a generalization of 4-point binary nonstationary SSs. The proposed scheme produces a limit surface having $C^{1}$ C 1 smoothness. It generates circular images, spirals, or parts of conics, which are important requirements for practical applications in computer graphics and geometric modeling. We also establish the rules for arbitrary topology for extraordinary vertices (valence ≥3). The well-known subdivision Kobbelt scheme (Kobbelt in Comput. Graph. Forum 15(3):409–420, 1996) is a particular case. We can visualize the performance of the unified scheme by taking different values of the tension parameter. It provides an exact reproduction of parametric surfaces and is used in the processing of free-form surfaces in engineering.

Geometric Modeling of Cutter/Workpiece Engagements for Helical Milling With Flat End Mills

2007 ◽  
Author(s):  
Eyyup Aras ◽  
Derek Yip-Hoi
Keyword(s):  
Geometric Modeling ◽  
High Speed ◽  
Tool Path ◽  
Cutting Tool ◽  
Milling Process ◽  
Helical Milling ◽  
Mapping Technique ◽  
Depth Of Cut ◽  
Modeling Methodology ◽  
End Mills

Helical milling is a 3-axis machining operation where a cutting tool is feed along a helix. This operation is used in ramp-in and ramp-out moves when the cutting tool first engages the workpiece, for contouring and for hole machining. It is increasingly finding application as a means for roughing large amounts of material during high speed machining. Modeling the helical milling process requires cutter/workpiece engagements (CWEs) geometry in order to predict cutting forces. The calculation of these engagements is challenging due to the complicated and changing intersection geometry that occurs between the cutter and the in-process workpiece. In this paper we present a geometric modeling methodology for finding engagements during helical milling with flat end mills. A mapping technique has been developed that transforms a polyhedral model of the removal volume from Euclidean space to a parametric space defined by location along the tool path, engagement angle and the depth-of-cut. As a result, intersection operations are reduced to first order plane-plane intersections. This approach reduces the complexity of the cutter/workpiece intersections and also eliminates robustness problems found in standard polyhedral modeling and improves accuracy over the Z-buffer technique. The reported method has been implemented and tested using a combination of commercial applications. This paper highlights ongoing collaborative research into developing a Virtual Machining System.

Stability Analysis of the MRT-Based Compliant Polishing Tool System

2012 ◽  
Vol 201-202 ◽  
pp. 473-476
Author(s):  
Chong Yang Yuan ◽  
Di Zheng ◽  
Jian Ming Zhan ◽  
Li Yong Hu
Keyword(s):  
Geometric Modeling ◽  
Mixed Model ◽  
Simulation Software ◽  
Free Form ◽  
Cnc Milling ◽  
Element Analysis ◽  
Compliant Polishing ◽  
The Stability ◽  
Free Form Surfaces ◽  
Polishing Tool

In order to meet the needs for the precise polishing of free-form surfaces, a new compliant polishing tool system was designed based on a magnetorheological torque servo (MRT), and integrated into a CNC milling machine. Through analysis, it was pointed out that the key factor affecting the polishing quality of this system is the stability of the system. By means of the 3D geometric modeling software ProE, the finite element analysis software ANSYS, and the dynamic simulation software ADAMS, the rigid-flexible mixed model of the system was established and the stability of the polishing pressure and tool position was numerically analyzed.

Analytical Cut Geometry Prediction for Free Form Surface During Semi-Finish Milling

2013 ◽  
Author(s):  
Hendriko ◽  
Emmanuel Duc ◽  
Gandjar Kiswanto
Keyword(s):  
Computational Time ◽  
Free Form ◽  
Depth Of Cut ◽  
Solid Model ◽  
Workpiece Surface ◽  
Engagement Angle ◽  
Rough Milling ◽  
Five Axis ◽  
Toroidal Cutter

In five-axis milling, determination of continuously changing Cutter Workpiece Engagement (CWE) is still a challenge. Solid model and discrete model are the most common method used to predict the engagement region. However, both methods are suffering with the long computational time. This paper presents an analytical method to define CWE of toroidal cutter during semi-finishing of sculpture part. The workpiece from 2.5D rough milling is represented by a number of blocks. The length of cut at every engagement angle can be determined by calculating the outermost engagement point called upper CWE point. This point was determined by first assumed that the workpiece surface is flat. A recalculation for CWE correction is then performed for the engagement occurred in two workpiece blocks. The method called Z-boundary and X-boundary are employed to obtain the upper CWE point when the engagement occurred on toroidal side. Meanwhile Cylinder-boundary method was used when the engagement occurred on the cylinder side. The developed model was examined to ensure its accuracy. A sculptured surface part was tested by comparing the depth of cut generated by the simulation developed and the depth of cut measured by Unigraphic. The result indicates that the proposed method is very accurate. Moreover, due to the method is analytically, and hence it is efficient in term of calculation time.

Minimisation of specific cutting energy and back force in turning of AISI 1060 steel

2017 ◽  
Vol 232 (11) ◽  
pp. 2019-2029 ◽  
Author(s):  
Sourabh Paul ◽  
PP Bandyopadhyay ◽  
S Paul
Keyword(s):  
Cutting Tools ◽  
Tool Geometry ◽  
Depth Of Cut ◽  
Machining Parameters ◽  
Specific Cutting Energy ◽  
Nose Radius ◽  
Cutting Energy ◽  
High Feed ◽  
Individual Criterion ◽  
Carbide Inserts

A lot of research has been undertaken in the area of conventional machining to study the effect of process parameters, tool geometry, machining environment and so on on machinability. But only recently, the research community has started analysing the carbon footprint of manufacturing processes. But very few articles could be located that attempted simultaneous minimisation of specific cutting energy and back force over a wide domain of process and tool-geometric parameters. This article has experimentally studied the effect of variation in depth of cut, feed, nose radius and tool geometry on simultaneous minimisation of specific cutting energy and back force while turning AISI 1060 steel with uncoated carbide inserts under dry machining environment. Minimisation of specific cutting energy and back force as individual criterion leads to conflicting choice of machining parameters. A combined criterion based on specific cutting energy and back force has been defined and for the minimisation of the same, cutting tools with positive rake need to be used, with high feed and moderate depth of cut.

Development of Advanced Broaching Tool for Machining Titanium Alloy

2012 ◽  
Vol 445 ◽  
pp. 161-166
Author(s):  
Mohammed Sarwar ◽  
Mike Dinsdale ◽  
Julfikar Haider
Keyword(s):  
Surface Quality ◽  
Metal Removal ◽  
Removal Rate ◽  
Cutting Tools ◽  
Vital Role ◽  
Tool Geometry ◽  
Depth Of Cut ◽  
Good Surface ◽  
Tool Performance ◽  
Good Surface Finish

Broaching is a precision multipoint metal removal operation normally employed for manufacturing variety of complex parts having either internal or external features. Broaching can produce high precision and good surface finish at a high metal removal rate. The unique feature of a broach tool is that the feed/depth of cut for the teeth is built into the broach unlike other cutting tools. The tool design (e.g., rise per tooth and tooth geometry) play a vital role in the broach performance. A specially adapted machine tool modified to investigate a single broach tooth has been used. Cutting forces and material removal rate have been measured during experimental work for different combination of broaching parameters and broach tool geometry. The effect of the parameters on the surface quality produced has been established. The characteristics of chips formed have also been defined. Finally, optimum tooth geometry and rise per tooth have been recommended for tool performance, broached surface quality and efficient chip formation. The information provided in this paper will be beneficial for broach tool designers and manufacturing engineers.

Sign in / Sign up

Export Citation Format

Share Document