PID control timescale limits

[japhy]

I have motions in the time scale range of 0.150sec that I'd like to implement the NI PID controller on.  Is this type of event within the capabilities of labview to both sample and control such a motion?  I notice in examples and workshop demos that I and D terms are provided in minutes or portions of.  These events I am trying to control happen pretty quickly, so I'd like to know if this is even feasible.

Thanks for any input you can provide!

[Jordan_M]

LabVIEW can handle this type of control.  If you run LabVIEW on a desktop computer you can create control loops that complete in a few milliseconds.  I think this should be adequate for your needs, because I understand that a control loop shoud run about ten times faster than the time constant of the system you want to control.  If you need a faster loop rate you can run labview on a real-time platform, such as the compact rio chasis, which can run loops that complete in microseconds.  If you need even faster control, you can run labview on an FPGA target.

[japhy]

Can you provide any overall details that would aid in the successful implementation of such a control loop?  I'm new to labview and the PID toolkit so would be helpful to know some of the setup, obviously knowing that individual PID terms would need to be determined on the system itself.  Ie how do you set sampling freq of the PID control algorithm, does pre-filtering of data help/hurt with fast event, etc.

Thanks again!

[Jordan_M]

National instruments provides a tutorial that might be helpful.

[japhy]

Do you know if there is a services group within NI that would be able/willing to support such an effort if necessary?

[TYtanic]

Japhy,

If you have our Standard Service Program, then you can create a service request online at ni.com/support and our Applications Engineers can assist you if you have questions. If SSP isn't an option for you, then you still should be able to get the help you need on these forums!