How do I implement my own transfer function?

LabVIEW has lots of built-in controls and filters, but I want my own.

I want to send data I collect through a transfer function of my own
specification, such as a second order where I can specify frequency and
damping. Or even something much higher-order.

But I cannot figure it out. I played with the H(z) discrete transfer
function, but there is no output from it, even when I specify just a
1/z lag. And the H(s) doesn't even drag out of the palette.

Please help, I'm new to LabVIEW. I ultimately want to implement a
feedback control systems on a motor with a rate loop and outer position
loop. I should be able to easily implement such a super-simple thing,
but heck if I can figure it out.

Please post or email,
--
Dan Stephenson
Photos, movies, panos from the Europe, USA, plus N.Z.:
http://homepage.mac.com/stepheda

(remove nospam from email address to reply via email)

On Nov 10, 11:15*pm, Dan Stephenson <stephedanos...@mac.com> wrote:
> LabVIEW has lots of built-in controls and filters, but I want my own.
>
> I want to send data I collect through a transfer function of my own
> specification, such as a second order where I can specify frequency and
> damping. *Or even something much higher-order.
>
> But I cannot figure it out. *I played with the H(z) discrete transfer
> function, but there is no output from it, even when I specify just a
> 1/z lag. *And the H(s) doesn't even drag out of the palette.
>
> Please help, I'm new to LabVIEW. *I ultimately want to implement a
> feedback control systems on a motor with a rate loop and outer position
> loop. *I should be able to easily implement such a super-simple thing,
> but heck if I can figure it out.
>
> Please post or email,
> --
> Dan Stephenson
> Photos, movies, panos from the Europe, USA, plus N.Z.:http://homepage.mac..com/stepheda
>
> (remove nospam from email address to reply via email)

If you have a recent version of a full Labview Development System you
can use a Mathscript node to implement transfer functions. A
mathscript node can execute most Matlab functions. Labview's built in
help provides a lot more information on Mathscript nodes and you can
also search the examples that come with Labview for examples that use
mathscript nodes.

Howard

On 2008-11-11 10:41:24 -0600, hrh1818 <hrhan@att.net> said:

> If you have a recent version of a full Labview Development System you
> can use a Mathscript node to implement transfer functions. A
> mathscript node can execute most Matlab functions. Labview's built in
> help provides a lot more information on Mathscript nodes and you can
> also search the examples that come with Labview for examples that use
> mathscript nodes.
>
> Howard

Thanks Howard I've thought of that and for low order it would be easy.
You mean it'll just handle all the states for you?

But I still find it hard to believe LabVIEW cannot implement such as
super basic capability like sending the data acquisition signal through
a transfer function of my own specification.

--
Dan Stephenson
Photos, movies, panos from the Europe, USA, plus N.Z.:
http://homepage.mac.com/stepheda

(remove nospam from email address to reply via email)