Optimization of the 2 1/2 D Pocket Machining Using Multiple Tools

2011 ◽  
Vol 223 ◽  
pp. 918-927
Author(s):  
Leandro Costa de Oliveira ◽  
Tsuzuki Marcos de Sales Guerra
Keyword(s):  
Dynamic Programming ◽  
Voronoi Diagram ◽  
Pocket Machining ◽  
Machining Strategy ◽  
Corner Machining

This work presents some contributions for optimization of the 2 ½ D pocket machining. The machining strategy considered is divided in internal machining and corners machining. The internal machining is carried through equidistant paths to the contour (offset) made by using Voronoi’s Diagram and the corner machining follows the same principle. As the Voronoi Diagram is parametric, the spaces between the paths can change. Thus, the best situation of spacing between paths can be determined to optimize the process. By using Dynamic Programming, the best combination of dimensions of the available tools can also be identified to remove the material of the pocket in smaller time.

A Hybrid Approach to Polygon Offsetting Using Winding Numbers and Partial Computation of the Voronoi Diagram

2014 ◽  
Author(s):  
Greg Burton
Keyword(s):  
Voronoi Diagram ◽  
Recursive Algorithm ◽  
Hybrid Approach ◽  
Radius Of Curvature ◽  
Convex Polygons ◽  
Pocket Machining ◽  
Worst Case ◽  
Offset Curves ◽  
Complete Computation ◽  
Offset Curve

In this paper we present a new, efficient algorithm for computing the “raw offset” curves of 2D polygons with holes. Prior approaches focus on (a) complete computation of the Voronoi Diagram, or (b) pair-wise techniques for generating a raw offset followed by removal of “invalid loops” using a sweepline algorithm. Both have drawbacks in practice. Robust implementation of Voronoi Diagram algorithms has proven complex. Sweeplines take O((n + k)log n) time and O(n + k) memory, where n is the number of vertices and k is the number of self-intersections of the raw offset curve. It has been shown that k can be O(n2) when the offset distance is greater than or equal to the local radius of curvature of the polygon, a regular occurrence in the creation of contour-parallel offset curves for NC pocket machining. Our O(n log n) recursive algorithm, derived from Voronoi diagram algorithms, computes the velocities of polygon vertices as a function of overall offset rate. By construction, our algorithm prunes a large proportion of locally invalid loops from the raw offset curve, eliminating all self-intersections in raw offsets of convex polygons and the “near-circular”, k proportional to O(n2) worst-case scenarios in non-convex polygons.

Voronoi diagram-based tool path compensations for removing uncut material in 2½D pocket machining

2006 ◽  
Vol 38 (3) ◽  
pp. 194-209 ◽  
Author(s):  
M. Salman A. Mansor ◽  
S. Hinduja ◽  
O.O. Owodunni
Keyword(s):  
Voronoi Diagram ◽  
Tool Path ◽  
Pocket Machining

Aggressive Spiral Toolpaths for Pocket Machining Based on Medial Axis Transformation

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Nuodi Huang ◽  
Roby Lynn ◽  
Thomas Kurfess
Keyword(s):  
High Speed ◽  
Medial Axis ◽  
Removal Rate ◽  
Salient Feature ◽  
Machining Time ◽  
Additional Material ◽  
Pocket Machining ◽  
Direction Parallel ◽  
Medial Axis Transformation ◽  
Machining Strategy

High-speed machine tools typically provide high spindle speeds and feedrates to achieve an effective material removal rate (MRR). However, it is not possible to realize the full extent of their high-speed capabilities due to the sharp corners of toolpaths which are introduced by conventional machining strategies, such as contour- and direction-parallel toolpaths. To address this limitation, spiral toolpaths that can reduce the magnitude of sudden direction changes have been developed in previous researches. Nevertheless, for some pockets, the average radial cutting width is significantly decreased while the total length of the toolpath is significantly increased as compared to contour- and direction-parallel toolpath. In this situation, spiral toolpath may take more machining time. To overcome these drawbacks, an aggressive spiral toolpath generation method based on the medial axis (MA) transformation is proposed in machining pocket without islands inside, which refers to no additional material inside the counter. The salient feature of this work is that it integrates the advantages of both conventional contour-parallel machining strategy and the existing spiral toolpath machining strategy. The cutting width at each MA point is determined based on the diameter of the locally inscribed circle (LIC) of the MA point and the topological structure of MA. A distance-constrained contour determination algorithm is utilized to calculate the toolpath for each pass. Finally, a circular arc transition strategy is used to transform all the isolated passes into a spiral toolpath. Experiments are conducted to show the effectiveness of the proposed method.

scholarly journals Optimization of pocket machining strategy in HSM

2011 ◽  
Vol 62 (1-4) ◽  
pp. 69-81 ◽  
Author(s):  
El Bechir Msaddek ◽  
Zoubeir Bouaziz ◽  
Gilles Dessein ◽  
Maher Baili
Keyword(s):  
Pocket Machining ◽  
Machining Strategy

scholarly journals Development of Direction-Parallel Strategy for Shorting A Tool Path in The Triangular Pocket Machining

2019 ◽  
Vol 18 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Mochammad Chaeron ◽  
Budi Saputro Wahyuaji ◽  
Apriani Soepardi
Keyword(s):  
Path Length ◽  
Tool Path ◽  
Machining Efficiency ◽  
Machining Time ◽  
Pocket Machining ◽  
Direction Parallel ◽  
Numerical Examples ◽  
Tool Paths ◽  
Machining Strategy ◽  
Parallel Strategy

The machining strategy is one of the parameters which practically influences the time of the different manufacturing geometric forms. The machining time directly relates to the machining efficiency of the tool paths. In area milling machining, there are two main types of tool path strategies: a direction-parallel milling and contour-parallel milling. Then direction-parallel milling is simple compared with a contour-parallel strategy. This paper proposes a new model of the direction-parallel machining strategy for triangular pockets to reduce the tool path length. The authors develop an analytical model by appending additional the tool path segments to the basis tool path for cutting un-machined area or scallops, which remained along the boundary. To validate its results, the researchers have compared them to the existing model found in the literature. For illustrating the computation of this model, the study includes two numerical examples. The results show that the proposed analytic direction-parallel model can reduce the total length of machining. Thus, it can take a shorter time for milling machining.

Sign in / Sign up

Export Citation Format

Share Document