Automatic 5-axis NC toolpath generation

Despite over a decade of research, automatic toolpath generation has remained an elusive goal for 5-axis NC machining. This thesis describes the theoretical and practical issues associated with generating collision free five-axis roughing and finishing toolpaths automatically from the CAD model of the part. Instead of decomposing the shape into manufacturing primitives we generate the collision free tool paths directly from the shape of the workpiece by using accessibility arguments. Specific points of discussion in this thesis include: * A scheme for generating five-axis tool paths using "accessibility" as the driving constraint for tool path generation. * A scheme for approximating the "accessibility" of a class of tools with visibility because direct evaluation of accessibility information of a tool in a part has been shown to be computationally expensive by several researchers. Visibility of a point along an orientation is a necessary condition for accessibility. We have developed algorithms to compute the visibility information rapidly using graphics hardware. * A scheme for extracting the most "promising" orientation from the visibility information for the tool in a "global" sense. Algorithms to process the visibility information to select the orientation based on the characteristics of the machining process have been developed.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2001

Author dc:creator

• Balasubramaniam, Mahadevan, 1976-

Advisor dc:contributor.advisor

• Sanjay E. Sarma.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/29225

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/29225