Bosch Rexroth IndraDrive MPH-02 Functional Description page 515

MPH-02, MPB-02, MPD-02
Infinitely Turning Axis
Ambiguity of Target Position
Spindle Positioning
Out of Standstill
Spindle Positioning
Out of Motion
DOK-INDRV*-MP*-02VRS**-FK01-EN-P
Specific Features with "Modulo" Position Data Format
Spindles for machine tools or rotary axes mostly are infinitely turning
axes, their required position being within one revolution (0...360 dgr). For
those axes it is recommended to use the "modulo" position data format
because it allows displaying the actual position values with reference to
one axis revolution only.
With modulo scaling the target position is ambiguous because it occurs
within every spindle revolution. Depending on the direction of motion
("clockwise/counter-clockwise" or "shortest distance") preset for spindle
positioning and the velocity at which spindle positioning is started, the
positioning distance can be of different length. In addition, one or several
additional revolutions can be required until the target position has been
reached!
Out of standstill the spindle or rotary axis positions as determined in
S-0-0154, Spindle position parameter:
• with the selected direction of motion ("clockwise" or "counter-
clockwise")
- or -
• with the direction of motion in which the target position can be reached
over the shortest possible distance ("shortest distance")
Apart from the determined direction of motion (in S-0-0154), decelerating
and positioning the spindle out of motion depends on
• the absolute value of the current velocity
- and -
• the distance between current axis position and target position
at the start of spindle positioning.
The actual sequences of the positioning process of a turning axis can
differ in spite of the determined direction of positioning motion.
In order to improve the reproduction of the positioning process, further
limiting conditions are taken into account for the drive behavior:
• S-0-0418, Target position window in modulo mode
• S-0-0417, Positioning velocity threshold in modulo mode
8-83
Drive Functions