Questions on the use of Mathematica to analyze, design, and simulate continuous- and discrete-time control systems.

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7
votes
1answer
69 views

On using DiracDelta[t] in OutputResposne in version 10. Different result from version 9

I am baffled by this. I was trying to run same example I had working in version 9.01 and found now I get empty plots. The example is here . Here is a simplified version of the above. The same exact ...
4
votes
2answers
81 views

Laplace: from differential equation to transfer function

First at all, this is trictly related to my own question: How to transform transfer functions into differential equations? How can I transfer my differential equation into a transfer function? For ...
5
votes
1answer
367 views

Estimate parameters of the state space model

I'm using Mathematica 9 and its Control Systems functionality. I've searched the references extensively but seem not to be able to find any examples of state space model parameters estimation. All ...
0
votes
1answer
72 views

A problem with “RiccatiSolve::ncsol: Cannot compute a stabilizing solution to the matrix equation ”

I have a SSM ( State Space Model ) and I want to calculate its optimum gains unisng LQOutputRegulatorGains[] command. When I run the code, it solves the equations ...
4
votes
0answers
66 views

Why do NDSolve and OutputResponse not evaluate non-analytic functions numerically?

test = OutputResponse[TransferFunctionModel[1/(1 + s), s], Exp[-(1/t)], {t, 0, 10}] does not evaluate. If Exp[-(1/t)] is ...
0
votes
1answer
36 views

Multiplicate in an Integration with time [closed]

I am calculating the area of a step response. I try to use this Integral Criterion for my Calculation. The time t is multiplicated with the control error xd raised to the second power. ...
1
vote
0answers
34 views
4
votes
2answers
232 views

How to transform transfer functions into differential equations?

is there a way with Mathematica to transform transferfunctions (Laplace) into differential equations? Let's say I have the transfer function $\frac{Y(s)}{U(s)}=\text{Kp} \left(\frac{1}{s ...
3
votes
1answer
75 views

How to apply RootLocusPlot corectly

I have to analyze the complex regions of variable c which is define obtained with InverseLaplace help in the form ...
1
vote
1answer
194 views

Unit of the frequency axis in BodePlot

I have a simple question: What is the unit of the frequency axis in the BodePlot? I searched the documentation, but only found this: The scaling functions can be specified as ...
8
votes
1answer
415 views
1
vote
0answers
93 views

No response from DSolve

Using optimal control theory, I am trying to find the optimal paths of d and k such that they will maximize profit as given by lc: ...
0
votes
1answer
125 views

How to use NyquistPlot without having a transfer function model?

Could anyone tell me how to use NyquistPlot with a first argument that is not a transfer function model? The expression I'd like to pass to ...
3
votes
1answer
360 views

How to increase Maximum number of steps in any other functions except NDSolve?

I want to plot an output response from a state space model. I use StateResponse[] to calculate it and then plot it. When I run my code, I face this message: ...
5
votes
2answers
279 views
2
votes
1answer
1k views

How can I draw an asymptotic bode plot?

When I use Mathematica to draw a bode plot, it always gives the precise version, like this: BodePlot[(10 (s + 3))/(s (s + 2) (s^2 + s + 2))] How can I draw the ...
0
votes
1answer
390 views

How to simulate the response of a linear parametric varying system in Mathematica?

Consider the following system \begin{align} \dot{x}(t)&=\sum_{i=1}^{2}\rho_{i}(x(t))\left[A_{i}x(t)+B_{i}u(t)\right]\\ y(t)&=Cx(t) \end{align} with: ...
4
votes
2answers
897 views

How to fix BodePlot that comes with Mathematica?

I am using Mathematica to go through the examples and exercises on the book Modern Control Systems, 6th edition by Dorf. On page 605, there is a table (Table 8.5) with the Bode plot for several ...
4
votes
1answer
167 views

Problems with RootLocusPlot

I am having some trouble to understand how the RootLocusPlot works (options, drawing and etc.) Here is an example ...
12
votes
1answer
437 views

Simulating discrete time stochastic dynamic systems

What is the canonical way of simulating discrete time stochastic dynamical systems in Mathematica using the new functionality of Random processes? To take a concrete example, lets consider the ...
6
votes
1answer
625 views

Does Mathematica solve transfer functions differently to Matlab?

Please note this is an edit to the same question posed a few weeks back: I'm using Mathematica to derive the transfer functions for a three phase AC/DC inverter. Given below is the code for the ...
2
votes
2answers
449 views

Using transfer function model to generate state space model

I am trying to generate the state space model for the following system: However, the following code does not generate the state space model I expect: ...
4
votes
0answers
389 views

Kalman filter by hand

I am now learning the Kalman filter and wants to implement it by hand to understand it better. To be specific I want to first simulate a sequence of data by $$ \dot x=Ax+Bw\\ y=Cx+Dv,\\ ...
4
votes
1answer
215 views

Using the LQGRegulator to build a human operator model

I'm trying to build a human operator model using an optimal control model in Mathematica: The vehicle dynamics are given by ...
3
votes
1answer
243 views

How to adjust the parameters on a Nyquist Plot?

In order to see some details on a Nyquist Diagram I have used the function NyquistPlot that comes with Mathematica v8 and v9. ...
3
votes
3answers
266 views

Strange behaviour of OutputResponse

I am having some trouble when using OutputResponse. For instance consider the following command ...
6
votes
1answer
327 views

How to convert a transfer function model to a zero-pole-gain model?

Mathematica has a function to convert TransferFunctionModels to StateSpaceModels: ...
7
votes
1answer
220 views

How do you use SystemsModelFeedbackConnect?

I'm trying to grasp the new control system functions in Mathematica 8. I'd like to connect a controller model to a model of a plant to simulate the behavior of the system. I define a simple servo ...