A Novel Automatic Feedrate Adjustment Method for Die-Cavity Roughing

2005 ◽  
Vol 291-292 ◽  
pp. 625-630
Author(s):  
Min Jie Wang ◽  
Y.J. Cai ◽  
W.G. Yan
Keyword(s):  
High Speed ◽  
Tool Path ◽  
Orthogonal Cutting ◽  
Cnc Machining ◽  
Surface Model ◽  
Machining Time ◽  
Surface Machining ◽  
Cutter Deflection ◽  
Sculptured Surface Machining ◽  
Volumetric Models

Sculptured surface machining is a critical process commonly used in die and mold industries. Since there is a lack of scientific tools in practical process planning stages, feedrates of CNC machining are selected based on previous experiences. In the selection of feedrate, the feedrate is set an individual conservative constant value all along the die cavity roughing processes in order to avoid undesirable results such as chipping, cutter breakage or over-cut due to excessive cutter deflection. Usually, volumetric models or vector force models used for optimizaton of feedrates must be created to get the variable feedrates along the tool path. Considering the die cavity roughing being a 2.5D cutting, a novel cutting force surface model is created based on orthogonal cutting tests to adjust the feedrates. The model is tested by a typical die-cavity roughing, thinning down machining time and balanced cutting-load can be attained. The presented feedrate scheduling characterized by balancing the cutting-loads in die-cavity roughing will be more significative in high speed machining.

A New NURBS Tool Path Generation Algorithm for Precise Sculptured Surface Machining

2010 ◽  
Vol 97-101 ◽  
pp. 2477-2480
Author(s):  
Xu Jing Yang ◽  
Guang Yong Sun ◽  
Qing Li
Keyword(s):  
Manufacturing Industry ◽  
Tool Path ◽  
Tool Path Generation ◽  
Surface Model ◽  
Sculptured Surface ◽  
Path Generation ◽  
New Approach ◽  
Surface Machining ◽  
Sculptured Surface Machining ◽  
Fitting Algorithm

This paper proposes a new approach to tool path generation in precision machining of parts with sculptured surface. It aims to develop an effective NURBS fitting algorithm suitable for machining sophisticated parts requiring smooth profile on sculptured surface. In order to generate NURBS tool path with fewer control points, a dual-loop fitting technique is proposed in this paper. A general sculptured surface model is used to test the effectiveness of this method. It is shown that the proposed algorithm proved to be robust and effective in generating precise NURBS tool path. This makes the proposed algorithm suitable to convert conventional CNC tool path to more precise NURBS tool path. This approach may be of potential to be widely implemented in the manufacturing industry.

A Swept Ellipse Offsetting Approach for Three-Axis Sculptured Surface Tool Path Generation

2004 ◽  
Author(s):  
Peter Jang ◽  
James A. Stori
Keyword(s):  
High Speed ◽  
Tool Path ◽  
Contact Point ◽  
Tool Path Generation ◽  
Sculptured Surface ◽  
Path Generation ◽  
Surface Machining ◽  
Tool Paths ◽  
Sculptured Surface Machining ◽  
Processing Techniques

This paper presents a new offsetting approach for tool path generation in three-axis sculptured surface machining. The approach generates tool paths with scallop, curvature, and force characteristics which make them suitable for high speed machining. An ellipse in the parametric space is used to approximate the intersection between the ball-end mill and the scallop surface for any cutter contact point on the surface. The envelope formed by these swept ellipses of varying dimension and orientation creates a constant scallop curve which is used to generate offset paths. The offset is developed incrementally, utilizing post-processing techniques to eliminate high-curvature regions in the trajectory. The offsetting approach can generate continuous spiraling trajectories which offer the benefit of minimal tool retractions. Results are shown for spiraling paths generated from both convex and non-convex boundaries.

A Line and Arc Transition Tool Radius Compensation Algorithm for Convex Contour

2012 ◽  
Vol 542-543 ◽  
pp. 1167-1171
Author(s):  
Chun Wang ◽  
Sheng Lin ◽  
Quan Hai Peng
Keyword(s):  
High Speed ◽  
Tool Path ◽  
Cnc Machining ◽  
Work Piece ◽  
Sharp Corner ◽  
Machining Time ◽  
Tool Paths ◽  
Long Time ◽  
Tangent Direction ◽  
Radius Compensation

Tool radius compensation is necessary to CNC machining. However, B tool radius compensation leads to work piece burning at the sharp corner of convex contour because of the long time contacts between the work piece and tool, and C tool radius compensation frequently changes machining feed rate for its broken line tool path. This paper presents a novel tool radius compensation method suitable for high speed machining of convex contour, which have the advantages of both B and C tool radius compensation. It uses compound transition with line and arc between the adjacent blocks of CNC program. The offset tool paths of the adjacent blocks extend a small line segment respectively along their tangent direction, then insert an arc between the end points of the two extended line segments. The results of simulation and experiments show that the machining quality of the sharp corner of convex contour is improved and the machining time is shorter than C tool radius compensation.

Effect of Tool Path Strategies in Pocket Milling of Aluminium Epoxy

2014 ◽  
Vol 903 ◽  
pp. 15-20 ◽  
Author(s):  
Rusdi Mat Song ◽  
Safian Sharif ◽  
Ahmad Yasir Md Said ◽  
Mohd Tanwyn Mohd Khushairi
Keyword(s):  
Computer Aided Design ◽  
High Speed ◽  
Tool Path ◽  
High Speed Steel ◽  
Cutting Parameters ◽  
Cnc Machining ◽  
Numerical Control ◽  
Machining Time ◽  
Pocket Milling ◽  
Cad Cam

Selection of the most suitable tool path strategy is very essential during machining especially in computer aided design and manufacture (CAD/CAM) as well as computer numerical control (CNC) machining. Existence of various tool path strategies to be applied on advanced composite materials such as aluminium epoxy required extensive researches in determining the best combination of tool path and cutting parameters for better machinability performance. Pocket milling of aluminium epoxy specimen via CAD/CAM was conducted in this study to investigate the effect of three types of tool path strategies namely Inward Helical, Outward Helical and Back and Forth. Uncoated high speed steel (HSS-Co8) ball end mill was used throughout the experiments. The machining responses that were evaluated include machining time, tool wear rate, tool life and surface finish of the machined pockets. In general, the effect of tool path strategy was highly significant on the machining responses and results showed that Back and Forth strategy offered the best machinability results when compared to the other strategies.

Research on Five-Axis Dual-NURBS Adaptive Interpolation Algorithm for Flank Milling

2010 ◽  
Vol 443 ◽  
pp. 330-335 ◽  
Author(s):  
Yu Han Wang ◽  
Jing Chun Feng ◽  
Sun Chao ◽  
Ming Chen
Keyword(s):  
Tool Path ◽  
Flank Milling ◽  
Interpolation Algorithm ◽  
Machining Time ◽  
Surface Machining ◽  
Tool Axis ◽  
Scanning Area ◽  
Nurbs Interpolation ◽  
Milling Method ◽  
Five Axis

In order to exploit the advantages of five-axis flank milling method for space free surface machining to the full, a definition of non-equidistant dual-NURBS tool path is presented first. On this basis, the constraint of velocity of points on the tool axis and the constraint of scanning area of the tool axis are deduced. Considering both of these constraints, an adaptive feed five-axis dual-NURBS interpolation algorithm is proposed. The simulation results show that the feedrate with the proposed algorithm satisfies both of the constraints and the machining time is reduced by 38.3% in comparison with the constant feed interpolator algorithm.

Interactive and Collaborative Virus-Evolutionary CNC Machining Optimization Environment

2015 ◽  
pp. 110-141
Author(s):  
N. A. Fountas ◽  
N. M. Vaxevanidis ◽  
C. I. Stergiou ◽  
R. Benhadj-Djilali
Keyword(s):  
Cnc Machining ◽  
Machining Parameters ◽  
Sculptured Surfaces ◽  
Surface Machining ◽  
Theory Of Evolution ◽  
Sculptured Surface Machining ◽  
Novel Approach ◽  
Manufacturing Software ◽  
Machining Strategies ◽  
Machining Optimization

Research on the area of sculptured surface machining optimization is currently directed towards the implementation of artificial intelligence techniques. This chapter aims at presenting a novel approach of optimizing machining strategies applied to manufacture complex part geometries. Towards this direction a new genetic-evolutionary algorithm based on the virus theory of evolution is developed as a hosted module to a commercial and widely known CAM system. The new genetic algorithm automatically evaluates pairs of candidate solutions among machining parameters for roughing and finishing operations so as to optimize their values for obtaining optimum machining programs for sculptured parts in terms of productivity and quality. This is achieved by introducing new directions of manipulating manufacturing software tools through programming and customization. The environment was tested for its efficiency and has been proven capable of providing applicable results for the machining of sculptured surfaces.

Region based Efficient CNC Machining using Point Cloud Data

2020 ◽  
pp. 1-35
Author(s):  
Mandeep Dhanda ◽  
Aman Kukreja ◽  
Sanjay Pande
Keyword(s):  
Path Planning ◽  
Surface Quality ◽  
Point Cloud ◽  
Tool Path ◽  
Cnc Machining ◽  
Real Surface ◽  
Tool Path Planning ◽  
Machining Time ◽  
Cloud Data ◽  
Planning Strategy

Abstract This paper presents an efficient tool path planning strategy for three-axis CNC machining using curvature based segmentation (CBS) of freeform surface from its representation in the form of a point cloud. Curvature parameters estimated over the point data are used to partition the surface into convex, concave, and saddle like regions. Grid based adaptive planar tool path planning strategy is developed to machine each region separately within its boundaries. In addition to the region by region machining, strategy to stitch the obtained regions is also developed to minimize the tool lifts and tool marks. The developed region based tool path planning strategy is compared with the point cloud based adaptive planar strategy, iso-scallop strategy and commercial software for parts with various complexities. The result shows significant improvement in terms of performance parameters viz. machining time, tool path length and code length while maintaining the desired part surface quality. The proposed method is also tested by machining a real surface and analyzing its surface quality.

An Intelligent Approach to Multiple Cutters of Maximum Sizes for Three-Axis Milling of Sculptured Surface Parts

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
Zezhong C. Chen ◽  
Gang Liu
Keyword(s):  
Tool Path ◽  
Generic Model ◽  
Interference Detection ◽  
Sculptured Surface ◽  
Surface Machining ◽  
Tool Paths ◽  
Sculptured Surface Machining ◽  
Cutter Selection ◽  
Intelligent Approach ◽  
Local Gouging

Due to their complex geometries, sculptured surface parts should be machined with multiple cutters of optimal sizes for high quality and productivity. Current methods of determining cutter sizes, however, are conservative and inefficient; their repeating process includes subjective cutter selection, intensive tool-path generation, and time-consuming gouging-and-interference detection in simulation. Our research proposes a new intelligent approach to multiple standard cutters of maximum sizes for three-axis sculptured surface machining. An innovative generic model of maximum allowable cutters in three-axis surface milling is built to eliminate any cutter causing local gouging and global interference. After the optimum standard cutters are automatically selected, their accessible regions can be identified, and the corresponding tool-paths can be generated, respectively. This approach is practical and effective in the process planning for three-axis milling of sculptured surface parts.

Optimized NURBS Based G-Code Part Program for High-Speed CNC Machining

2014 ◽  
Author(s):  
Sai Ashish Kanna ◽  
Andres Tovar ◽  
Jason Soungjin Wou ◽  
Hazim El-Mounayri
Keyword(s):  
Code Generation ◽  
High Speed ◽  
Tool Path ◽  
Optimization Method ◽  
Cnc Machining ◽  
Part Program ◽  
Tool Trajectory ◽  
Minimum Number ◽  
G Code ◽  
Gear Profile

This work presents the automation of high-accuracy CNC tool trajectory planning from CAD to G-code generation through optimal NURBs surface approximation. The proposed optimization method finds the minimum number of NURBS control points for a given admissible theoretical cord error between the desired and manufactured surfaces. The result is a compact part program that is less sensitive to data starvation than circular and spline interpolations with potential better surface finish. The proposed approach is demonstrated with the tool path generation of an involute gear profile.

Sign in / Sign up

Export Citation Format

Share Document