Post-Processors

The Wire EDM Post-Processors

I wrote three programs to convert the WIRE EDM ROBOFIL ISO part programs output by the New Profil Compiler (np) to other models of WIRE EDMs.

Picture 1: A ROBOFIL 300 WIRE EDM.

These post-processor programs were first developed using the WICAT Pascal language compiler on Wicat computers running the multi-user, multi-tasking operating system MCS.

In 1991, they were ported to UNIX (IRIX on Silicon Graphics) using the MIPS Pascal language compiler.

The Post-Processors Input

The New Profil Language generates ISO part programs for the Charmilles ROBOFIL 200-400 CNC machines. The post-processors convert these part programs to other target EDM machines while performing some validations and error checking.

At the plant, there were several variety of wire EDM machines. In 1999, the plant had the nine following wire EDM machines:

Picture 2: A Charmilles F45

• One 2-axis Charmilles F45
• One 4-axis Japax LU3B
• One 4-axis Mitsubishi DWC200
• One 5-axis Charmilles Robofil 200
• One 5-axis Charmilles Robofil 400
• Two 5-axis Charmilles Robofil 300
• One 5-axis Charmilles Robofil 500
• One 5-axis Charmilles Robofil 510

The ISO part program for the various brands of machine is slightly different. For example, some machines require that the coordinates are specified in absolute reference mode, other may require that the coordinates are specified incrementally (i.e. as a displacement relative to the previous position). Some machines have a feature to change rapidly the value of the offset at the beginning or at the end of a segment that is tangent to the next or previous one, other machines cannot change the offset unless the segments intersect at a right angle.

Picture 3: A Japax LU3B

Picture 4: A Mitsubishi DWC200

Also, the machines have different characteristics that are not the same. For example, a ROBOFIL 200 can cut at a taper angle of 27˚ whilst a Mitsubishi is limited to a taper of 10˚.

The goal of the post-processors is to adapt the Robofil ISO and to make it work on other machines while insuring that no errors or discrepancies be introduced during the translation.

There are so much other things I could explain about the post-processors, but because of my oath to industrial secrecy, I cannot disclose these trade secrets.