Answered

Designing LQR controller error

The system might be controllable in principle, but in reality seems to be problematic for using state feedback. I had trouble ev...

Designing LQR controller error

The system might be controllable in principle, but in reality seems to be problematic for using state feedback. I had trouble ev...

10 hours ago | 0

Answered

How can I plot the transfer function? HELP Please.

Because you want to make plots, I'm going to assume that you have numerical values for each parameter in your model. For exampl...

How can I plot the transfer function? HELP Please.

Because you want to make plots, I'm going to assume that you have numerical values for each parameter in your model. For exampl...

2 days ago | 1

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Answered

How should I create a Transfer function with nth order polynomial term in denominator in simulink?

The power operator works for SISO tf and zpk objects. For example: >> h=exp(-0.2*tf('s'))*zpk([],-1,1)^5 h = ...

How should I create a Transfer function with nth order polynomial term in denominator in simulink?

The power operator works for SISO tf and zpk objects. For example: >> h=exp(-0.2*tf('s'))*zpk([],-1,1)^5 h = ...

4 days ago | 0

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Answered

why my plot is not correct?

If you're looking for a plot with odd symmetry, try: plot(x,nthroot(x,3)) % check doc nthroot for details

why my plot is not correct?

If you're looking for a plot with odd symmetry, try: plot(x,nthroot(x,3)) % check doc nthroot for details

5 days ago | 1

Answered

Display rotation matrix with s1, c1, etc. in place of sind(theta1), cosd(theta1), etc. respectively.

Use subs: >> doc subs >> syms theta1 s1 c1 >> A=[cos(theta1) sin(theta1);-sin(theta1) cos(theta1)] A = [ cos(theta1)...

Display rotation matrix with s1, c1, etc. in place of sind(theta1), cosd(theta1), etc. respectively.

Use subs: >> doc subs >> syms theta1 s1 c1 >> A=[cos(theta1) sin(theta1);-sin(theta1) cos(theta1)] A = [ cos(theta1)...

5 days ago | 0

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Answered

Why is the convolution so different from the analytical answer?

When approximating the continuous convolution with a discrete convoluton, the discrete convolution needs to be multilplied by dt...

Why is the convolution so different from the analytical answer?

When approximating the continuous convolution with a discrete convoluton, the discrete convolution needs to be multilplied by dt...

6 days ago | 1

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Answered

Plotting responses other than step responses to transfer function

Looks like an fplot() confusion issue. This code results in the expected plot: >> syms t; y(t) = ilaplace(1/s*poly2sym(T.Numera...

Plotting responses other than step responses to transfer function

Looks like an fplot() confusion issue. This code results in the expected plot: >> syms t; y(t) = ilaplace(1/s*poly2sym(T.Numera...

6 days ago | 0

Answered

Find the 5-point DFT of the sequence:

The code posted has a few issues. The second line is: >> u = sin(j) u = 0.0000e+00 + 1.1752e+00i >> whos u Name...

Find the 5-point DFT of the sequence:

The code posted has a few issues. The second line is: >> u = sin(j) u = 0.0000e+00 + 1.1752e+00i >> whos u Name...

8 days ago | 0

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Answered

Cannot compute Riccati solution for LQI controller

I'm not sure it's relevant, but should the fifth row of SYS.c be all zeros? I suspect the issue is with stabilizability of the ...

Cannot compute Riccati solution for LQI controller

I'm not sure it's relevant, but should the fifth row of SYS.c be all zeros? I suspect the issue is with stabilizability of the ...

8 days ago | 0

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Answered

How to solve a symbolic complex equation with real and imaginary parts?

I'm not sure what "change the paramters of the solve function" means. If a general apprach is desired, maybe something along the...

How to solve a symbolic complex equation with real and imaginary parts?

I'm not sure what "change the paramters of the solve function" means. If a general apprach is desired, maybe something along the...

9 days ago | 1

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Answered

Problem with integrating Sin to Cos

If you just want ode in terms of cos() >> ode = int(sin(n*x),x,0,pi/2) ode = (2*sin((pi*n)/4)^2)/n >> rewrite(ode,'...

Problem with integrating Sin to Cos

If you just want ode in terms of cos() >> ode = int(sin(n*x),x,0,pi/2) ode = (2*sin((pi*n)/4)^2)/n >> rewrite(ode,'...

12 days ago | 0

Answered

Simbolic simplification of trigonometric functions

How about this: >> simplify(f,500) ans = -(sin(x)*(- sin(x)^2 - c)^(1/2)*(sin(x)^2 - 1)^2)/(2*d^2)

Simbolic simplification of trigonometric functions

How about this: >> simplify(f,500) ans = -(sin(x)*(- sin(x)^2 - c)^(1/2)*(sin(x)^2 - 1)^2)/(2*d^2)

13 days ago | 1

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Answered

How to generate correlated samples from a single distribution? Each sample should be correlated with the previous.

I don't think the questionn is well posed. The question and the code make it sound like there is a single distribution and the s...

How to generate correlated samples from a single distribution? Each sample should be correlated with the previous.

I don't think the questionn is well posed. The question and the code make it sound like there is a single distribution and the s...

16 days ago | 0

Answered

how can i use symsum to make function with a variable apart from syms k?

This code works for the specified sequences. It would need to be modified if either x[n] or y[n] take on non-zero values for n <...

how can i use symsum to make function with a variable apart from syms k?

This code works for the specified sequences. It would need to be modified if either x[n] or y[n] take on non-zero values for n <...

16 days ago | 0

Answered

Problems with the controllability matrix.

ctrb() in the Control System Toolbox only accepts numeric inputs. If you have numeric values for the variables, you can substit...

Problems with the controllability matrix.

ctrb() in the Control System Toolbox only accepts numeric inputs. If you have numeric values for the variables, you can substit...

17 days ago | 0

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Answered

Making a transformation matrix in matrix format

You're not getting 4, 1 x 4 matrices. It just looks like that because of the formatting to the diplay. >> syms th d alph l A...

Making a transformation matrix in matrix format

You're not getting 4, 1 x 4 matrices. It just looks like that because of the formatting to the diplay. >> syms th d alph l A...

17 days ago | 0

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Answered

How to shift state space models by equilibrium points using ss and lsim?

The states, inputs, and outputs of Sys are all perturbations from the equilibrium solution. The intiial condition to lsim (x0) w...

How to shift state space models by equilibrium points using ss and lsim?

The states, inputs, and outputs of Sys are all perturbations from the equilibrium solution. The intiial condition to lsim (x0) w...

19 days ago | 0

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Answered

Differntial equations and Initial conditions

The initial conditions are set to represent the initial conditions of the system to be simulated. What other considerations migh...

Differntial equations and Initial conditions

The initial conditions are set to represent the initial conditions of the system to be simulated. What other considerations migh...

19 days ago | 0

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Answered

Matlab Code for DTFT to get frequency response

n, h, and w are all defined as row vectors and the * operator is trying to do matrix multiplication. But what you really want i...

Matlab Code for DTFT to get frequency response

n, h, and w are all defined as row vectors and the * operator is trying to do matrix multiplication. But what you really want i...

20 days ago | 0

Answered

Help with simplifying a complex symbolic expression

This code eliminates U_j0: [num,den]=numden(term1); newnum = combine(num,'log','IgnoreAnalyticConstraints',true); newterm1 = ...

Help with simplifying a complex symbolic expression

This code eliminates U_j0: [num,den]=numden(term1); newnum = combine(num,'log','IgnoreAnalyticConstraints',true); newterm1 = ...

21 days ago | 0

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Answered

Laplace Transform for ODE - RC Circuit

I think that last subs command is getting confused because q is defined as the solution of the ode. I'm not sure why that's a pr...

Laplace Transform for ODE - RC Circuit

I think that last subs command is getting confused because q is defined as the solution of the ode. I'm not sure why that's a pr...

23 days ago | 1

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Answered

Fourier Transformation of dirac comb

There is one too many points in the signal y. If you plot([y y]) and zoom in you'll see the pulse at sample 1001 immediately ...

Fourier Transformation of dirac comb

There is one too many points in the signal y. If you plot([y y]) and zoom in you'll see the pulse at sample 1001 immediately ...

25 days ago | 1

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Answered

Convert s in j*ω in a transfer function

No need to change anything in sys. It is a tf object and either freqresp() or bode() can evaluate sys at s = j*w doc freqresp ...

Convert s in j*ω in a transfer function

No need to change anything in sys. It is a tf object and either freqresp() or bode() can evaluate sys at s = j*w doc freqresp ...

25 days ago | 1

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Answered

How to find DTFT of given sequence in matlab

Assuming that y(n) = 0 for abs(n) > 5, there are are only three values of n for which y(n) is non-zero. Put those values of n an...

How to find DTFT of given sequence in matlab

Assuming that y(n) = 0 for abs(n) > 5, there are are only three values of n for which y(n) is non-zero. Put those values of n an...

25 days ago | 0

Answered

Printing out pi as a symbol in equations instead of the numerical value

If I understand the problem, it appears the idea is to define a function, an_Id, that can be used for both numerical evaluation ...

Printing out pi as a symbol in equations instead of the numerical value

If I understand the problem, it appears the idea is to define a function, an_Id, that can be used for both numerical evaluation ...

27 days ago | 0

Answered

probability - execution of an operation

If T has a normal distribution, then doc normcdf can be used to find the probability P(T < t)

probability - execution of an operation

If T has a normal distribution, then doc normcdf can be used to find the probability P(T < t)

27 days ago | 0

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Answered

Calculating and Plotting Weibull Distribution Function(wblpdf) with Cell Arrays

Here's an example that you might be able to adapt to your needs. >> params = {[1 2];[2 3];[3 4]}; % define cell array with par...

Calculating and Plotting Weibull Distribution Function(wblpdf) with Cell Arrays

Here's an example that you might be able to adapt to your needs. >> params = {[1 2];[2 3];[3 4]}; % define cell array with par...

1 month ago | 0

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Answered

I want to find where the root locus branches cross the y axis.

One option would be to use the return values of rlocus: [r,K]=rlocus(G1) to get a coarse idea of the value of K that results i...

I want to find where the root locus branches cross the y axis.

One option would be to use the return values of rlocus: [r,K]=rlocus(G1) to get a coarse idea of the value of K that results i...

1 month ago | 1

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Answered

Convert transfer function writing form

Maybe something like this: >> H = tf([15 25 1],[5 0 5],-1) H = 15 z^2 + 25 z + 1 ----------------- 5 z^2 + 5...

Convert transfer function writing form

Maybe something like this: >> H = tf([15 25 1],[5 0 5],-1) H = 15 z^2 + 25 z + 1 ----------------- 5 z^2 + 5...

1 month ago | 1

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Answered

Is it possible to manually connect the ABCD matrices to obtain the ss representation

Need to modify two lines of code as follows: clc; clear all; k = 1; m = 1; b = 1; A = [0 1; -k/m -b/m]; B = [0 1/m]'; C ...

Is it possible to manually connect the ABCD matrices to obtain the ss representation

Need to modify two lines of code as follows: clc; clear all; k = 1; m = 1; b = 1; A = [0 1; -k/m -b/m]; B = [0 1/m]'; C ...

1 month ago | 0

| accepted