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Re: Derivative function

From: A S Hodel
Subject: Re: Derivative function
Date: Wed, 19 Feb 2003 12:58:21 -0600

The octave controls toolbox is a part of Octave; the simulation language used in this lecture notes series is, unfortunately, not available for public use (export controlled). I originally used these notes in 6-month "short" course at Marshall Space Flight Center. The simulation language is a NASA - internal simulation tool that I used to obtain linearizations. This is the source of the syntax confusion. The MSFC simulation tool was used to obtain LTI dynamic models that were loaded into octave data structures
(see functions tf2sys, ss2sys, zp2sys, etc.).

I've thought about writing a translator to convert a differential equations list (such as that in my examples) to Octave code (m-file or .oct file). I'm making some progress on some
other areas, but it's also export controlled, so I can't put it out.

It would be great to have some simulink-like capability to:
(1) easily describe dynamic systems (in either block diagram or differential/difference
     equation form, and
(2) obtain linearizations from these dynamic system descriptions. These linearizations
   become the [a,b,c,d] matrices in the octave controls toolbox.

Wish lists: they're not just for Christmas anymore.

On Wednesday, February 19, 2003, at 12:45 PM, Henry F. Mollet wrote:

I have just looked at the lecture notes by A. Scottedward Hodel on
Introductory Controls Using the Octave Control Systems Toolbox. The example of the damped mass-spring system on p. 19/20 is implemented, among other
code with the following code line:
: pos-x'' = (1.0/mass) * (......... - pos_x) - alpha*pos_x'
Where pos_x and first and second derivative of pos_x appear.

Question: Is the Octave Control Systems Toolbox different from Octave and
can it be considered a symbolic math package?

Question: if pos_x' is the derivative, how is it distinguished from the
complex conjugate transpose operator " ' "? (Transpose operator is " .' "

A. S. Hodel, Assoc. Prof, Dept. Elect & Comp Eng, Auburn University, AL 36849-5201 (334) 844-1854 200 Broun Hall address@hidden

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