# Fanuc Series 15i/150i-MA (Programming) Operators Manual

B-63324EN/03 PROGRAMMING 19.AXIS CONTROL FUNCTIONS
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19.8 MULTIPLE ROTARY CONTROL AXIS FUNCTION
Explanation
A rotary axis is specified in the ROT bit (bit 1 of parameter 1008).
When incremental programming is specified for the rotary axis, a
specified value directly determines the travel distance. When absolute
programming is selected, either of the following two operations can be
specified by the RSR bit (bit 2 of parameter 1007).
(1) The NC unit rounds down the value specified in the absolute
command (G90) to a value indicating a full turn or less. The
difference between the rounded value and the current position is
the angular displacement. When the bit 5(INC) in parameter No.
1007 is specified, short-cut control can be executed. When the
difference between the rounded value and the current position
indicates more than a half turn, the short-cut control function
allows reverse rotation up to the specified position.
(2) The sign of the specified value indicates the direction of rotation.
(The plus sign (+) indicates counterclockwise rotation and the
minus sign (-) clockwise rotation). The absolute value of the
specified value indicates the destination.
- Position display
An absolute value of a position relative to the rotary axis is represented
by an equivalent value within the amount of travel for a single
revolution as specified in parameter 1260.
Example
When the rotary axis is called the B-axis, the following sample
programs control the rotary axis as shown below:
(1) When both the RSR bit (bit 2 of parameter 1007) and the INC bit
(bit 5 of parameter 1007) are set to 0
The NC internally converts the specified value to an equivalent
value within a single revolution. The difference between the
converted value and the value of the current position is regarded as
being the amount of travel.
[Example]
G90B0 ; Movement to the 0-degree position
G90B380. ; Rotation by 20 degrees in the positive direction. The
destination is the 20-degree position.
G90B-90. ; Rotation by 250 degrees in the positive direction. The
destination is the 270-degree position.
G90B60. ; Rotation by 210 degrees in the negative direction. The
destination is the 60-degree position.