You would need to setup something on the Galil that would sweep through open loop profiles to the amplifier/driver. From there you would need to look at the encoder feedback and the motor command output from the Galil.

For more information send me an e-mail at support@galilmc.com

I guess my question wasn't clear. I don't want the Galil to become a DSA. I have a DSA (a physical piece of hardware made by HP to excite and measure systems) and I want to apply it to a system that has a Galil controller in it. So can I put the Galil in an open loop mode, excite the system by connecting to some external inputs on the Galil, and measure the response via external outputs on the Galil?

It depends on the output and the possible inputs on the DSA.

Is it an analog output? If so, what is the voltage range? Can it output a quadrature or step and direction signal? Which controller model do you have? What type of signals can the DSA receive?

You have to feed the encoder output from the motor into the DSA in order to get the open loop response of the system.

What would almost make more sense is to bypass the controller and feed the output of the DSA to the amplifier directly. In the setup you are describing, the controller itself will contribute very little to the open loop response.

DSA's input and output +/-10V analog signals. It would be nice to have the Galil in the path since it would handle both commutation, in the case of multi-phase motors, encoder conditioning (e.g. translating a quadrature signal to an analog voltage). The time delays inherent to the Galil controller would also be captured by the DSA in such a setup.

I'm using a DMC 2020 controller and Advanced Motion Controls SE30A40AC amplifier.

You can run the analog output of the DSA to an analog input on the controller. Then put the controller in analog feedback mode (AF) for that axis, set KP to a non-zero value, and KD and KI to 0. The controller will just act as a proportional gain stage based on the KP value.

You still have to put the encoder data into the DSA in order to get the open loop response of the system.

How would I "wire" (internally via Galil commands) the analog inputs to a particular axis so that it could be used in analog Feedback mode?

Also, I noticed that there are two analog outputs available that may be useful to me: Error Output and High Speed Position Compare Output. What is the difference between these two signals? Also, is there a drawing of a block diagram that shows these signals?

Information on analog feedback can be found in the command reference under the AF command.

The Error Output and the High Speed Position Compare Output are digital outputs.
For more information on these signals see Error Output and Output Compare in the manual.

A functional block diagram of the controller can be found in Chapter 1 of the manual.

Link to Manual
http://www.galilmc.com/support/manuals/man2100.pdf

Link to Command Reference
http://www.galilmc.com/support/manuals/manc2xxx.pdf

Thanks for the references.

Are there any analog outputs available that can be mapped to internal signals?

There are no general use or uncommitted analog outputs on the DMC-2020. You have to use the motor command outputs (which are +/-10V analog outputs).

Ok... so do you, or anyone else at Galil, know of a device that can convert sine/cosine encoder output to an analog position or velocity signal?

For the DMC-4000 series controllers, we have the ICM-42100 that converts sin/cos encoders to position data. For the DMC-21x3 series controllers we have the DB-28104 that performs the same function.

For the DMC-20x0 controller you will need an external sin/cos interpolator. They typically take the sin/cos encoder data and create a quadrature signal. You should contact your local Galil Representative for product recommendations. You can use our rep finder on the website, or e-mail support@galilmc.com for contact information.

Rep Finder
http://66.60.181.132/xnet/findgalilrep.aspx

Thanks for all the info!