NX Rotary angle output from the Main MCS and the XYZ position from the Local MCS

A tombstone is set up on a horizontal mill with numerous parts mounted on each side. The controller for this machine does not use any swiveling commands such as G68.2, CYCLE800 or PLANE SPATIAL. Instead, the B axis rotary output needs to be taken from the MAIN_MCS. The XYZ positions will come from a LOCAL_MCS located somewhere on each one of the parts. What needs to be done in NX and Post Builder to get this type of posted output?

Solution

1. Define an MCS on the center of the rotary axis with the purpose set to Main.

2. Define an MCS on each part with the purpose set to Local and the special output set to CSYS Rotation. The LOCAL_MCS are placed under the MAIN_MCS in the Operation Navigator.

3. The CSYS Rotation setting unlocks a post variable array named mom_init_pos. This variable is only available when the CSYS Rotation is used.

4. In Post Builder edit the words being used to output the fourth axis angles. Look in the Canned Cycles, Linear Move and Rapid Move Events. Normally these use the $mom_out_angle_pos(0) variable. Select User Defined Expression to change this to use the $mom_init_pos(3) variable instead.

5. The caveat is that this is a permanent change and the setup will need to have the MCS definitions as described above all the time. If support for swiveling is also needed then Output Condition will need to be used to output the original variables.

Notes and References

Hardware/Software Configuration

Platform: all
OS: n/a
OS Version: n/a
Product: NX
Application: CAM
Version: V1919
Function: POSTBUILDER

Ref: 001-9441223