IAI America PDR-101-MW - Manual (Page 76)

66
(2) The Actual Speed does not Follow Commands Well
The actual speed is abnormally slow compared to the commanded speed, vibrations occur during
movement, it takes long for the positioning to complete, etc.
„
Increase the “position control loop proportional gain.” See (17) in Section 6.3.2.
„ Set the “position command primary filter time constant” to “0.” See (18) in Section 6.3.2.
„ Increase the “speed loop gain.” See (28) in Section 6.3.2.
„ Decrease the “speed loop integration time constant.” See (29) in Section 6.3.2.
If command signals are not followed well because the load weight is heavy or the sliding resistance is large,
it is possible to make adjustments so that the response to command pulse signals becomes faster.
[Points]
1) Position control loop proportional gain
Position command signals are followed better if this value is set larger.
Set the value in the range from 30 to 50 as a guideline. An even higher value can be set as
far as the operation characteristics of the system’s mechanical parts are ensured.
However, over-shoot tends to occur if the value is set too large.
2) Position command primary filter time constant
As explained in (1), this parameter should be set when it is desirable to slow down the
response. Thus, set this parameter to “0” (or a small setting value) to improve the response
speed.
3) Speed loop gain
Speed command signals are followed better if this value is set larger.
In order to secure the stability of the control system, which may have been lowered by
increasing the position control loop proportional gain, raise the speed loop gain as well.
Note, however, that if this value is set too large, the mechanical parts of the system tend to
vibrate.