## Multivariable control via Transfer Matrices?

Started by in comp.dsp17 years ago 2 replies

reading my old copy of 'Modern Control Engineering' by Ogata, 1970, (ok, no longer 'modern'), pg 117 describes a method of multivariable control...

reading my old copy of 'Modern Control Engineering' by Ogata, 1970, (ok, no longer 'modern'), pg 117 describes a method of multivariable control using a 'transfer matrix' of Laplace transfer functions where Gij(s) is the transfer function from ith input to jth output. Would this be practical to actually implement? Assuming I could model each Gij(s) as a simple 2nd order function, and only ...

## Parametric description of Transfter function for 4th order Bessel filter

Started by in comp.dsp16 years ago 5 replies

Hi, Does anyone know of a parameteric description for the transfer function (in Laplace domain) of a 4th order Bessel Thompson LPF, in terms...

Hi, Does anyone know of a parameteric description for the transfer function (in Laplace domain) of a 4th order Bessel Thompson LPF, in terms of its 3dB bandwidth? If not, is there an empirical way to scale the filter coeffs to get a specific 3dB cut off point? Thanks, Venugopal

## Re: laplace tranform convert to code

Started by in comp.dsp15 years ago

tim w wrote: > Hello all, > > I need some guidance in programming a laplace transfer function into > computer language -- pseudocode for...

tim w wrote: > Hello all, > > I need some guidance in programming a laplace transfer function into > computer language -- pseudocode for now. > > The transfer function is a second order function: > > To^2*s^2 + zeta1*To*s + 1 > ------------------------- > To^2*s^2 + zeta2*To*s + 1 > > From what i've read the above transfer function is a bandstop filter, Zeta1 > and Zeta2 are adj

## Re: laplace tranform convert to code

Started by in comp.dsp15 years ago

Tim Wescott wrote in news:iv-dncPJu77Y1VzZnZ2dnUVZ_oadnZ2d@web-ster.com: > tim w wrote: > > Hello all, > > > > I need some...

Tim Wescott wrote in news:iv-dncPJu77Y1VzZnZ2dnUVZ_oadnZ2d@web-ster.com: > tim w wrote: > > Hello all, > > > > I need some guidance in programming a laplace transfer function into > > computer language -- pseudocode for now. > > > > The transfer function is a second order function: > > > > To^2*s^2 + zeta1*To*s + 1 > > ------------------------- > > To^2*s^2 + zeta2*

## Re: laplace tranform convert to code

Started by in comp.dsp15 years ago

tim w wrote: > Tim Wescott wrote in > news:iv-dncPJu77Y1VzZnZ2dnUVZ_oadnZ2d@web-ster.com: > > > > tim w wrote: > > > > > Hello...

tim w wrote: > Tim Wescott wrote in > news:iv-dncPJu77Y1VzZnZ2dnUVZ_oadnZ2d@web-ster.com: > > > > tim w wrote: > > > > > Hello all, > > > > > > I need some guidance in programming a laplace transfer function into > > > computer language -- pseudocode for now. > > > > > > The transfer function is a second order function: > > > > > > To^2*s^2 + zeta1*To*s + 1 > > > -----------------

## Re: laplace tranform convert to code

Started by in comp.dsp15 years ago

Tim Wescott wrote: > tim w wrote: ... > > -Also, the variable "fc" is the corner frequency. What is that on how do > > I set...

Tim Wescott wrote: > tim w wrote: ... > > -Also, the variable "fc" is the corner frequency. What is that on how do > > I set it??? > In a band stop filter fc is the center frequency of the stop band. In > your transfer function everything is scaled in time, with "To". For fc > in Hz, fc = 1/(2 * pi * To). Other tim, Remember to prewarp the critical frequencies. Rick's book go

## Re: laplace tranform convert to code

Started by in comp.dsp15 years ago

Jerry Avins wrote: > Tim Wescott wrote: > > > tim w wrote: > > > ... > > > > -Also, the variable "fc" is the corner...

Jerry Avins wrote: > Tim Wescott wrote: > > > tim w wrote: > > > ... > > > > -Also, the variable "fc" is the corner frequency. What is that on how do > > > I set it??? > > > > In a band stop filter fc is the center frequency of the stop band. In > > your transfer function everything is scaled in time, with "To". For > > fc in Hz, fc = 1/(2 * pi * To). > > > Other tim, > > R

## Re: laplace tranform convert to code

Started by in comp.dsp15 years ago

> tim w wrote: > > Hello all, > > > > I need some guidance in programming a laplace transfer function into > > computer language --...

> tim w wrote: > > Hello all, > > > > I need some guidance in programming a laplace transfer function into > > computer language -- pseudocode for now. > > > > The transfer function is a second order function: > > > > To^2*s^2 + zeta1*To*s + 1 > > ------------------------- > > To^2*s^2 + zeta2*To*s + 1 > > That is similar to a notch filter. I posted a link to a notch filter desi

## Mildly OT: Strange posts recently

Started by in comp.dsp14 years ago 4 replies

Hi Guys, I've been absent from this newsgroup for many weeks now, and this morning I scanned through the recent posts starting with the...

Hi Guys, I've been absent from this newsgroup for many weeks now, and this morning I scanned through the recent posts starting with the month of May. I was shocked to see so many posts requesting the solutions to problems that sure sounded like homework problems to me. (Laplace transforms, solving differential equations, solving for bilear transformations, etc.) One guy actua...

## Re: how to design LPF given i/p signal its sampling freq, reqiured o/p, in MATLAB

Started by in comp.dsp13 years ago

hai every one,First of all thanks for all your quick response t=0:0.05:5;X=1+sin(pi*t); plot(t,X) Since ,the required o/p is 1(in time...

hai every one,First of all thanks for all your quick response t=0:0.05:5;X=1+sin(pi*t); plot(t,X) Since ,the required o/p is 1(in time domain). I thought if i should get the o/p as 1, the LP filter coefficients had to be designed in such a way so as to get the reqiured o/p as 1. i multiplied with x(t) and y(t) with u(t) [step function] x(t)=[1+sin(pi*t)]u(t) ; y(t)=u(t) I took Laplace tra...

## s-plane; Laplace; Smith book

Started by in comp.dsp12 years ago 4 replies

hi, I would like some clarification on Smith's description on p. 544. The material is discussed between p. 537 - p. 544 Specifically, the...

hi, I would like some clarification on Smith's description on p. 544. The material is discussed between p. 537 - p. 544 Specifically, the regions of convergence, or value boundedness, or no-convergence in the s-place. Q: On the surface, it looks fine. However, the details of the specific descriptions of the pole/zero a-e fig 30-4 appear to me confusing (as far as I can understand the...

## re: s-plane; Laplace; Smith book

Started by in comp.dsp12 years ago 8 replies

thanks Rick and Jerry for the reply. The book is the first printing of the Smith book. Will furnish details in a moment: I'm still...

thanks Rick and Jerry for the reply. The book is the first printing of the Smith book. Will furnish details in a moment: I'm still searching for the words to describe what I'm after. In particular, in the several days since the orig. post, I've learned that the words "convergence" and unbounded" are steps toward discovery of what and how to determine stability. I'm clearly intereste...

## generating step output : matlab issues

Started by in comp.dsp11 years ago

hi, I have a transfer function. I want to find the input waveform which will give me a step waveform at the output. If H is the...

hi, I have a transfer function. I want to find the input waveform which will give me a step waveform at the output. If H is the transfer function, I try to find x(t) by taking the inverse laplace of 1/(s.H). But if I feed x(t) back to H, I do not get the output as a step. Instead I get something else totally different. Is my matlab code given below ok? The matlab code is below %defin...

## Hiring a DSP programmer

Started by in comp.dsp10 years ago 33 replies

Hi All Where is the best place to hire a programmer for a DSP/Laplace control system Thanks Tinkerz

Hi All Where is the best place to hire a programmer for a DSP/Laplace control system Thanks Tinkerz

## Simulation of Laplace Distributed Noise

Started by in comp.dsp9 years ago 4 replies

I am doing some testing of blind source estimation schemes and require higher-order statistical noise. I only have Gaussian and normal...

I am doing some testing of blind source estimation schemes and require higher-order statistical noise. I only have Gaussian and normal distributions. Is it possible to shape these in some way to make a Laplace distribution? (to model speech - I know I could use real speech but I want more control over things). Thanks

## Did you know - LMS

Started by in comp.dsp9 years ago 33 replies

That the LMS derivation and equation is only optimal for Guassian driving signals. If the driving noise through an unknown system has some other...

That the LMS derivation and equation is only optimal for Guassian driving signals. If the driving noise through an unknown system has some other form of distribution (say Laplace as is the case with speech), then the best estimator of that FIR system is the simpler sign() LMS. I found this quite a pleasant surprise. Hardy

## impact of noise in zero-padded region of filtered time trend data

Started by in comp.dsp9 years ago 10 replies

I included a Matlab program below you can run to illustrate my question (or just look at the output I placed in the comments below the code). Note...

I included a Matlab program below you can run to illustrate my question (or just look at the output I placed in the comments below the code). Note that I'm using a small set of data below to simplify this question (the real app uses much more data). This code: 1. zero pads an example (all real) 10-element array 2. takes its FFT 3. creates a Laplace (s-domain) filter and applies it to the ...

## Modeling Issues (difference equation to Laplace)

Started by in comp.dsp7 years ago 7 replies

First off, Hello all. I am new here. I have been working on a project for some time and have came to a point where I am stuck. I have...

First off, Hello all. I am new here. I have been working on a project for some time and have came to a point where I am stuck. I have researched some technical papers and can not figure out how someone came from point a in the paper (a difference equation) to point b ( a transfer function in the s domain). If anyone can shed light on the matter it would be greatly appreciated. The equations a...

## Following peer review - the derivation of the representation of sampling by Diracian Delta functions

Started by in comp.dsp7 years ago 3 replies

Revised after peer review, approached with a little less haste So... Sampling with a period of T is given by (after asciification) as...

Revised after peer review, approached with a little less haste So... Sampling with a period of T is given by (after asciification) as .. (1/T)sum (n : 0, inf)(d(t-nT) * f(nT) ) ... with * representing multiplication and not convolution as we are still in the time domain. However, (and this is where my protest came in having previously fully revised Fourier, Laplace, Butterworth...

## Impulse invariance method

Started by in comp.dsp2 years ago 1 reply

I have a laplace transfer-function G(s)=k(1+sT)/s*2 which I need the discrete-time version G(z) using impulse invariance method. Using...

I have a laplace transfer-function G(s)=k(1+sT)/s*2 which I need the discrete-time version G(z) using impulse invariance method. Using partial fractions I get G(s) = c1/s + c2/s^2 c1=kT and c2=k However when I use Matlab c2d and select "impulse" it gives me a different version though the first term c1 is right. Matlabs second term c2 is negative. I assume for multiple pole...