0
Research Papers

Towards a Five-Axis Machining CAPP System: A Set-Up Planning Tool Solving Accessibility Constraints

[+] Author and Article Information
V. Capponi

Institute of Production and Robotics, Ecole Polytechnique Fédérale de Lausanne EPFL-STI-IPR-LICP, Station 9, CH-1015 Lausanne, Switzerlandvincent.c@postmail.ch

F. Villeneuve

 G-SCOP Laboratory, 46, Avenue Félix Viallet, FR-38031 Grenoble, Francefrancois.villeneuve@g-scop.inpg.fr

Mechanical parts that must be manufactured using a five-axis machine-tool because of their complex geometry are called “five-axis parts.”

For instance, a typical generic pocket strategy could be composed of three stages, namely, global roughing, bottom finishing, and flank finishing.

This assumption relies on the case of an easily accessible plane face and depends on the diameter of the end-mill.

This strategy may let a visible line on the surface which is acceptable for aircrafts parts.

Ruled surfaces are the result of moving a straight line along a certain trajectory. Planar and cylindrical faces are particular ruled ones, and will be considered out of the group of ruled surfaces in this paper.

The best-fit stock may be the minimum material one or may be defined to ease the set-up fixture by providing two good quality location planes in the required orientation.

Usually 90% of the studied parts are machined in a “double face” strategy, i.e., in two opposite setups (Cap 04). If not, the planner keeps the same approach to find the two first setups and add an extra one using a third side of the stock.

The considered bounding box for this material volume calculation does not take into account the different fixtures elements, so the calculated volume will be slightly different from the real stock used.

In this case, the BEM mode for closed-angled flanges (F61 for instance) will correspond to a sweeping strategy with a toric ball cutter.

It is by the way the setup currently used to machine this part in one of the company we studied.

11The tests were done on a computer with a 3Ghz CPU (Pentium 4™ )

These rules are usually precedence or data selection ones that ensure the respect of the quality specifications of the part.

J. Comput. Inf. Sci. Eng 9(4), 041003 (Oct 29, 2009) (14 pages) doi:10.1115/1.3243632 History: Received September 29, 2006; Revised May 07, 2009; Published October 29, 2009

The overall aim of the authors’ work is to create a computer aid to support the macroplanning of five-axis parts, and in this context this paper presents the methodology developed to enable the determination of set-up orientations on five-axis machine-tools. The process starts with an access model that encompasses all the machining directions encountered in five-axis operations. Then an enhanced visibility-based modeling and algorithm are proposed in order to solve accessibility constraints while planning the setups for double-sided parts. The proposed algorithm is illustrated on an industrial aircraft structural part. To conclude, options to integrate the proposed method in a computer assisted process planning system are discussed.

Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

The “ADLA component” workpiece at the end of the machining

Grahic Jump Location
Figure 2

Technologically equal milling operations and associated machining time

Grahic Jump Location
Figure 3

Alternatives directions for plane milling

Grahic Jump Location
Figure 6

Examples of mandatory directions from the ADLA component

Grahic Jump Location
Figure 7

Definition of Real Visibility Map, 2D view (adapted from Ref. 29)

Grahic Jump Location
Figure 8

Instance of machine-maps in previous works

Grahic Jump Location
Figure 15

The simplified test part and its feature decomposition

Grahic Jump Location
Figure 16

Visibility map of the test part.

Grahic Jump Location
Figure 4

Alternatives directions and strategies for a plane with joggle edge

Grahic Jump Location
Figure 5

Sets of continuous directions for a ruled surface.

Grahic Jump Location
Figure 9

Three types of machining access: (a) single, (b) multiple, and (c) cone

Grahic Jump Location
Figure 10

Access map of a plane on the ADLA component

Grahic Jump Location
Figure 11

Machine Map of the considered five-axis machine-tool

Grahic Jump Location
Figure 12

Parameters modeling the set-up orientation (part orientation about the machine-tool axis)

Grahic Jump Location
Figure 13

Parameters to define the set-up orientations

Grahic Jump Location
Figure 14

Step 2, normal orientation algorithm (output is a range of (α+; α−))

Grahic Jump Location
Figure 17

Three solutions of neutral planes

Grahic Jump Location
Figure 18

Implemented VB Macro in CATIA V5 ™

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In