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General
준호
준호
Posted about 12 hours ago

How to maintain eigenvalues sequence

Hello,
I have to draw root-locus for longitudinal motion; Short Period Mode and Phugoid Mode. Here is a code
%% Dynamics
Vp = 111.174
A_lon = [-0.0283 0.3139 -11.0665 -32.0344;
-0.4204 -1.5452 108.6931 -3.2616;
0.0205 -0.2011 -3.5080 0;
0 0 1 0]
B_lon = [0.0115 0.1150;
-0.2185 0;
-0.3591 0;
0 0]
C_lon = [1 0 0 0;
0 -1 0 Vp]
%% LQR Servo Design
A_servo = [A_lon zeros(4,2);
-C_lon zeros(2,2)]
B_servo = [B_lon ; zeros(2,2)]
n = 100; a = logspace(-2,2,n);
for i = 1:n
Q = a(i)*[1 0 0 0 0 0;
0 1 0 -Vp 0 0;
0 0 0 0 0 0;
0 -Vp 0 power(Vp,2) 0 0;
0 0 0 0 1 0;
0 0 0 0 0 1];
R = eye(2);
[K,S,P] = lqr(A_servo,B_servo,Q,R);
p_cl = P;
cl_sh(i,1) = p_cl(5); cl_sh(i,2) = p_cl(6);
cl_ph(i,1) = p_cl(3); cl_ph(i,2) = p_cl(4);
end
%% Plot
figure;
plot(real(cl_sh(:,1)), imag(cl_sh(:,1)), '+', real(cl_sh(:,2)), imag(cl_sh(:,2)), 'x', MarkerSize=5);
title("Root Locus of Short Period Mode")
xlabel("real")
ylabel("imag")
grid on;
figure;
plot(real(cl_ph(:,1)), imag(cl_ph(:,1)), '+', real(cl_ph(:,2)), imag(cl_ph(:,2)), 'x', MarkerSize=5)
title("Root Locus of Phugoid Mode")
xlabel("real")
ylabel("imag")
grid on;
When the code is executed, the sequence of eigenvalues is misaligned from some point in the iteration statement and the point was depended on weight of Q, R matrix. So when the sequence of eigenvalues is out of order from a certain point in time like this, how should we modify the code to solve it?
General
Hello,
What is the difference between a moving angle and a normal angle?
Compute the Rotation about Y-axis over moving angle a = 30°
then
rotation about X-axis of angle β= 45°
What will the code like?
Thank you
General
Engineer
Engineer
Posted on 30 Nov 2023 at 12:13

Error C MEX S-function

Hello there, I have a Amesim Black box model in Simulink. On my desktop, it works well. Also i tried to run on other desktops. Most of them work well. But some of them gives following error: Error in 'Model' while executing C MEX S-function 'Model', (mdlInitializeConditions), at time 0.0. Caused by: in Simcenter Amesim mexfunction: 'Model', Simcenter Amesim fatal error Cannot initialize Simcenter Amesim Model. EXIT This is an urgent case for me. Could you please help me?

Thank you so much.

Generative AI
Kali
Kali
Posted on 30 Nov 2023 at 5:57

Help

Write a matlab script that will print the odd numbers, 1 through 20, in reverse.
I cannot figure out how to do this correctly, please help.
General
Dear Community,
I am trying to perform PowerGUI Loadflow analysis for EV Charging station. The model converges but the load flow vaues on the DC bus is zero. Whether power_loadflow supports Mixed AC/DC load Flow.
Can someone help me by providing guidance on how to preform the same
Regards
Vara
Contests
ABOAJELA
ABOAJELA
Posted on 29 Nov 2023 at 15:53

damping circuit

i need circuti to model wound rotor synchronous machine damping circuit in matlab simulink , is there any one know how to do it
General
when I build the model I get the name mismatch error for two calibratable signals . The signals are in the data dictionary , and I use them in the model by pulling from the dd with the same name . can anyone point me out what possibly cause this error?
General
Ayush
Ayush
Posted on 29 Nov 2023 at 10:06

facing an issue in

we have extracted a .xml file from solidworks to import in matlab, when we tried to import it shows that simscape multibody should be installed and when we tried to install it it shows the message attached below.
we are working on an educational license provided by our university, is it the issue?
General
It is crucial to understand that this expression could be used in problems related to engineering, physics, mathematics, or any other aspect of real life.
Typically, Matlab is used to solve PDE and ODE problems. Perhaps users calculated this term 0^0 incorrectly in the process.
>> % Reviewed by Bewar Yousif Ali
>> % How to fix this problem 0^0 in Matlab !?
>> % Mathematically, x^0=1 if x≠0 is equal 1 else undefined(NaN)
>> 0^0
ans =
1
>> f=@(x,y) x^y;
>> f(0,0)
ans =
1
>> v=[2 0 5 -1];
>> v.^0
ans =
1 1 1 1
Highlights
What amazing animations can be created with no more than 2000 characters of MATLAB code? Check out our GALLERY from the MATLAB Flipbook Mini Hack contest.
Vote on your favorite animations before Dec. 3rd. We will give out MATLAB T-shirts to 10 lucky voters!
Tips: the more you vote, the higher your chance to win.
General
i=dsolve('Dy=-8*y+40*sin(8*t)','y(0)=5')
Warning: Support for character vector or string inputs will be
removed in a future release. Instead, use syms to declare
variables and replace inputs such as dsolve('Dy = -3*y') with syms
y(t); dsolve(diff(y,t) == -3*y). > In dsolve (line 126)
Contests
JAMEEL
JAMEEL
Posted on 24 Nov 2023 at 21:27

Error at , can not run M = A\b;

% Given data
x = [2.0, 3.0, 6.5, 8.0, 12, 15];
f = [14, 20, 17, 16, 23, 125];
% Construct the cubic spline
h = diff(x);
A = zeros(length(x)-2);
for i = 1:length(x)-2
A(i,i) = 2*h(i) + 2*h(i+1);
A(i,i+1) = h(i+1);
A(i+1,i) = h(i);
A(i+1,i+1) = 2*h(i) + h(i+1);
end
b = [6*(f(2)-f(1))/h(1) + 6*(f(3)-f(2))/h(2);
6*(f(4)-f(3))/h(3) + 6*(f(5)-f(4))/h(4)];
M = A\b;
% Evaluate the second derivative at data points
d2f_dx2 = zeros(length(x),1);
for i = 1:length(x)-2
d2f_dx2(i) = M(i);
d2f_dx2(i+1) = M(i) + h(i)*M(i+1);
d2f_dx2(i+2) = M(i) + 2*h(i)*M(i+1) + h(i)*h(i)*M(i+2);
end
% Display second derivatives at data points
disp('Second Derivatives at Data Points:');
disp(d2f_dx2);
General
Sanika Patil
Sanika Patil
Posted on 24 Nov 2023 at 9:22

face recognition GUI

Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback Error while evaluating Button PrivateButtonPushedFcn.
help to solve this error in face recognition GUI
Contests
i've finished writing the code for my ~masterpiece~ and it doesn't run on the contest new entry page. it runs on matlab on my desktop and in the matlab live editor in my browser, but not where i really need it to. usually it'll draw the first frame the first time i run the code in a new window, but not any subsequent times. whether i hit "run" or "create animation", the screen grays out as it's supposed to, but then returns to normal without generating the first frame or animation.
i'm not getting a timeout warning or any error messages. i timed the code on my laptop and it takes about 100ish seconds to run and generate the animation the first time i run it before clearing everything from my workspace (and then it takes about twice as long each subsequent time, which makes me a bit nervous. can't figure out why this is the case at all!), which is well within the 255 second limit for the contest. as far as i know, the most computationally expensive function i'm using is patch(). i'm pretty close to the character limit, but i don't know if that's part of the problem.
i tried vectorizing some of the code instead of using for loops, which made the code run slightly slower. i tried using a nested function instead of using drawframe() and an auxiliary function, but that didn't help. i tried clearing all variables except f at the end of drawframe() to no avail. i tried using the close command at the start of drawframe(), with similar success. i updated chrome, closed a bunch of windows, tried safari, used my sister's laptop, all with no luck.
has anyone else had this or a similar problem? any advice?
thanks!
General
丰 年
丰 年
Posted on 23 Nov 2023 at 6:35

打开matlab 示例 提示错误

打开matlab 示例 提示错误,提示“系统找不到指定的文件”
General
Shaunak Deshpande
Shaunak Deshpande
Posted on 20 Nov 2023 at 7:44

Error using tall/cellfun

I'm getting an error error "using tall/cellfun" while doing a project listed in mathworks "Denoise Speech Using Deep Learning Networks". I don't know how to fix this error pr why this error occured in the first place. Seeking explanation for this particuar error. If you know anuthing about it then please consider helping me below this post.
Project link
Off Topic
Elija
Elija
Posted on 20 Nov 2023 at 5:18

What Should I Opt For MY SQL?

Hello, all!
This is my first post after just joining this discussion, so please forgive me and provide kind assistance if I have posted to the wrong subsection!
I have a good interest in learning sql server course and right now I am taking help from various platforms like https://www.coursera.org/ https://www.udemy.com/
Also I have a doubt that is it a good option to learn from platforms like this or I should go for some sql server online training . I have searched for the solution of my queries in various above platforms which helped me up to some extent only as it was not directly given by any expert or trainer.
Hoping in getting a quick response
Thankyou in advance.
General
柯
柯
Posted on 20 Nov 2023 at 1:39

Two-phase flow solenoid valve

Hello, I want to use a solenoid valve to open and close the two-phase flow circuit, and I should use those elements to achieve it.