Rockwell Automation GMLC Reference Manual - Manual (Page 272)

Publication GMLC-5.2 - November 1999
Interpolate Axes 235
Helical Interpolation
To enable helical interpolation, you must first enable the third and fourth
physical axes (Axis2 and Axis3) in the General page of the Configure
Control Options General dialog box.
When you select Helical from the Type menu, the selected Z axis moves
either the set distance (in Incremental mode), or to the specified
destination position (in Absolute mode) while the selected X axis and Y
axis move through the specified arc angle (in turns), in the selected
direction, along a circular path whose center is at the set point, and
produces the same motion as shown previously for absolute mode. This
results in helical motion, a threading or spiraling of the three axes.
Example 7: Helical Interpolation in Absolute Mode
For example, if the following bullets are true, and the Interpolate Axes
parameters are as shown below, it uses Interpolator 0 to move Axis 2 to an
endpoint of 5 position units, while Axis 0 and Axis 1 make two complete
revolutions around a circle centered at X = –5, Y = 5 in a clockwise
direction, as shown in the diagram below.
• Axis 0 is used as the X axis and is currently at absolute position –10
position units
• Axis 1 is used as the Y axis and is currently at position +10 position
units
• Axis 2 is used as the Z axis and is currently at position –5 position
units