Delta RMC151 - Manual (Page 46)

RMC70/150 and RMCTools User Manual
absolute command should be on the order of 20 -100 pu/sec 2 . The speed is
typically between 1 and 30 pu/sec.
2. View the Plot
When you issue a command in the Tuning Tools, the plot is automatically
uploaded from the RMC. The plot will help you determine which parameters
must be changed.
In the Tuning Tools, you can easily disable the automatic plot upload for one
of the command buttons. If you are focusing on tuning a certain direction, you
can keep the plot from uploading when moving the other direction.
3. Change a Tuning Parameter
Change a gain in the Axis Parameters section of the Tuning Tools. After
changing the value you must click the download button or press Ctrl+D to
download the changes to the RMC.
4. Repeat these steps
Repeat these steps until the parameter is at the desired value.
• Use the Mean Squared Error
The Mean Squared Error in the RMCTools Plot Manager can help determine how the
last parameter change affected the system. The Mean Squared Error provides a rough
indication of how closely the Actual Position is tracking the Target Position. If this
number decreases significantly, the last parameter change was good. If this number
increases significantly, the last parameter change was bad.
• Start with Long, Slow Moves, then Use Faster Moves
Begin the tuning procedure with fairly long, slow moves and low accelerations. This
will prevent you from losing control of and potentially damaging the system. The
moves should be short enough to fit in the plot.
After gaining control of the system, you should increase the speed to values you
expect to use during machine operation. Always tune your system at the speeds of
intended operation.
• Set Auto Stops
You may want to turn off some of the Auto Stop bits. The Auto Stops cause the axis to
halt if an error occurs. In the initial stages of tuning, a Following Error or other error
may occur, causing an undesired halt. Setting these bits to "Status Only" will make the
RMC ignore the errors so you can tune the axis. Once you gain sufficient control of the
axis, set the Auto Stop bits to halt. Turning off the Auto Stops may not be possible on
some systems because of safety concerns.
• Update Flash and Save the Project
When editing the parameters in the project, you must download them to apply the
changes to the RMC. However, they are not updated in the RMC's Flash memory until
you issue an Update Flash command. This will save the parameters even if power is
disconnected. To save the RMC's parameters to the project, upload the parameters
from the RMC and then save the project.
2.3.2. Tuning Wizard
The Tuning Wizard automatically calculates tuning gains for you. The wizard first guides you
through the process of obtaining plots, then automatically calculates a range of valid gains,
and finally presents you with a simple slider bar to choose conservative or aggressive gains.
The tuning wizard can be used with position, pressure and force axes. The tuning wizard
cannot be used for velocity axes.
The Tuning Wizard works as follows:
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