Automatic method for milling complex channel-shaped cavities

1. A method of milling a channel-shaped cavity to be performed by a five-axis computer numerical control (CNC) machine, the method comprising:

selecting a workpiece to be machined, wherein the workpiece has a bottom surface of a channel, a left wall of the channel, a right wall of the channel, and an entry point of a cutting tool;

determining a primary set of flank-milling positions of the cutting tool;

determining a trochoidal path for the cutting tool; and

determining auxiliary movements of the cutting tool, wherein determining auxiliary movements of the tool comprises a polishing finish pass, wherein the polishing finish pass is based on the determined trochoidal path for the cutting tool.

2. The method of milling a channel-shaped cavity of claim 1 , further comprising:

outputting one or more cutting tool movements as one or more machine instructions, wherein the one or more cutting tool movements is based on at least one of the selected workpiece, the determined primary set of flank-milling positions, the determined trochoidal path, and the determined auxiliary movements.

3. The method of milling a channel-shaped cavity of claim 1 , further comprising:

replicating, for each depth-level of an incrementally lower depth-level, at least one of:

determining a primary set of flank-milling positions of the cutting tool; determining a trochoidal path for the cutting tool; and determining auxiliary movements of the cutting tool.

4. The method of milling a channel-shaped cavity of claim 1 , wherein determining the primary set of flank-milling positions of the cutting tool further comprises:

analyzing the bottom surface of the workpiece channel;

determining possible geometric symmetries based on the analyzed bottom surface of the workpiece channel;

propagating curves containing the determined possible geometric symmetries onto the left wall of the workpiece channel and onto the right wall of the workpiece channel;

analyzing the left wall of the workpiece channel and analyzing the right wall of the workpiece channel;

determining the relative position of the left wall of the workpiece channel and the relative position of the right wall of the workpiece channel based on the analyzed left wall of the workpiece channel and right wall of the workpiece channel; and

generating an updated geometric database containing the propogated curves containing the determined possible geometric symmetries of the left wall of the workpiece channel and containing the determined possible geometric symmetry of the right wall of the workpiece channel relative to the bottom surface of the workpiece channel.

5. The method of milling a channel-shaped cavity of claim 1 , wherein determining auxiliary movements of the tool further comprises at least one of:

approaching a part of the workpiece; detaching the tool from a part of the workpiece;

connecting movements between sub-areas of the tool path as rapid links; adding a polishing finish pass; and determining a final tool path.

6. The method of milling a channel-shaped cavity of claim 1 , wherein determining the trochoidal path for the cutting tool further comprises:

determining a geometric cutting tool position;

determining a relative interaction of the workpiece to be machined and the determined geometric cutting tool position;

determining if the determined relative interaction of the workpiece to be machined and the determined geometric cutting tool position satisfies a defined set of technological constraints, wherein the defined set of technological constraints comprises at least one technological constraint;

if the defined set of technological constraints is not satisfied, then

determining a new geometric cutting tool position, wherein the determined new geometric cutting tool position is based on the determined relative interaction of the workpiece to be machined and the determined geometric cutting tool position, and the determined satisfaction of the at least one technological constraint; and

outputting the determined new geometric cutting tool position to be used in determining the relative interaction of the workpiece to be machined and the determined geometric cutting tool position;

if the defined set of technological constraints is satisfied, then accepting the geometric cutting tool position.

7. The method of milling a channel-shaped cavity of claim 6 , wherein determining the geometric cutting tool position further comprises:

determining a set of geometric cutting tool positions for the selected right wall of the workpiece channel;

verifying the determined set of geometric cutting tool positions for the selected right wall of the workpiece channel for non-colliding cutting tool positions with respect to the bottom surface of the workpiece channel;

reproducing any symmetries on the bottom surface of the workpiece channel;

modifying the determined set of geometric cutting tool positions for the selected right wall of the workpiece channel if at least one of the following occurs: a collision occurs with the bottom surface of the workpiece channel; and at least one technological constraint in the defined set of technological constraints is violated;

determining a set of geometric cutting tool positions for the selected left wall of the workpiece channel;

verifying the determined set of geometric cutting tool positions for the selected left wall of the workpiece channel for noncolliding cutting tool positions with respect to the bottom surface of the workpiece channel;

reproducing any symmetries on the bottom surface of the workpiece channel; and

modifying the determined set of geometric cutting tool positions for the selected left wall of the workpiece channel if at least one of the following occurs: a collision occurs with the bottom surface of the workpiece channel; and at least one technological constraint in the defined set of technological constraints is violated.

8. The method of milling a channel-shaped cavity of claim 7 , wherein determining the relative interaction of the workpiece to be machined and the determined geometric cutting tool position further comprises:

verifying the trochoidal path for the cutting tool does not collide with at least one of: the bottom surface of the channel, the left wall of the channel, and the right wall of the channel;

verifying the trochoidal path for the cutting tool does not generate a cutting tool engagement greater than a cutting tool engagement limit; and

verifying the trochoidal path for the cutting tool has a local curvature that permits the cutting tool to be moved at a speed above a set preferred speed limit.

9. A device for generating instructions for a five-axis machining tool, the device comprising:

a processing module having addressable memory, the processing module configured to:

repeat the following steps for a channel-shaped cavity, while at least one machining limitation parameter is not satisfied:

determine cutting tool flow along the channel-shaped cavity;

determine cutting tool in-depth penetration from a top surface of the channel-shaped cavity towards a bottom surface of the channel-shaped cavity;

determine a trochoid path for the cutting tool based on the determined cutting tool flow along the channel-shaped cavity and the determined cutting tool in-depth penetration; and

determine a polishing finish pass, wherein the polishing finish pass is based on the determined trochoid path for the cutting tool.

10. The device for generating instructions for a five-axis machining tool of claim 9 , wherein the processing module is further configured to:

select the channel-shaped cavity to be machined, wherein the channel-shaped cavity has a bottom surface, a left wall, a right wall, and an entry point of the cutting tool.

11. The device for generating instructions for a five-axis machining tool of claim 9 , wherein the processing module is further configured to:

determine auxiliary movements, wherein auxiliary movements are at least one of: approach the channel-shaped cavity; detach from the channel-shaped cavity; connect movements of the cutting tool between sub-areas; add a polishing finish pass; and determine a final tool path.

12. The device for generating instructions for a five-axis machining tool of claim 9 , wherein the at least one machining limitation parameter is at least one of: the geometric shape of the channel prohibits an additional pass, and the machining tolerance is less than required for an additional pass.

13. The device for generating instructions for a five-axis machining tool of claim 9 , wherein the step to determine the trochoid path for the cutting tool is further based on at least one of: an axial cutting tool engagement, a radial cutting tool engagement, an at least one cutting tool speed parameter, and an interaction of the bottom surface of the channel-shaped cavity with the trochoid path.

14. A method comprising:

selecting a workpiece to be machined, wherein the workpiece has a bottom surface of a channel, a left wall of the channel, a right wall of the channel, and an entry point of a cutting tool;

determining a primary set of flank-milling positions of the cutting tool; wherein the determining comprises:

analyzing the bottom surface of the workpiece channel;

determining possible geometric symmetries based on the analyzed bottom surface of the workpiece channel;

propagating curves containing the determined possible geometric symmetries onto the left wall of the workpiece channel and onto the right wall of the workpiece channel;

analyzing the left wall of the workpiece channel and analyzing the right wall of the workpiece channel;

determining the relative position of the left wall of the workpiece channel and the relative position of the right wall of the workpiece channel based on the analyzed left wall of the workpiece channel and right wall of the workpiece channel; and

generating an updated geometric database containing the propogated curves containing the determined possible geometric symmetries of the left wall of the workpiece channel and containing the determined possible geometric symmetry of the right wall of the workpiece channel relative to the bottom surface of the workpiece channel; and

determining a trochoidal path for the cutting tool.

15. A method comprising:

selecting a workpiece to be machined, wherein the workpiece has a bottom surface of a channel, a left wall of the channel, a right wall of the channel, and an entry point of a cutting tool;

determining a primary set of flank-milling positions of the cutting tool; and

determining a trochoidal path for the cutting tool, wherein the determining comprises:

determining a geometric cutting tool position;

determining a relative interaction of the workpiece to be machined and the determined geometric cutting tool position;

determining if the determined relative interaction of the workpiece to be machined and the determined geometric cutting tool position satisfies a defined set of technological constraints, wherein the defined set of technological constraints comprises at least one technological constraint;

if the defined set of technological constraints is not satisfied, then determining a new geometric cutting tool position, wherein the

determined new geometric cutting tool position is based on the determined relative interaction of the workpiece to be machined and the determined geometric cutting tool position, and the determined satisfaction of the at least one technological constraint; and

outputting the determined new geometric cutting tool position to be used in determining the relative interaction of the workpiece to be machined and the determined geometric cutting tool position;

if the defined set of technological constraints is satisfied, then accepting the geometric cutting tool position.