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Rik
Rik
上次活动时间: 2024-9-17

What frustrates you about MATLAB? #2

Similar to what has happened with the wishlist threads (#1 #2 #3 #4 #5), the "what frustrates you about MATLAB" thread has become very large. This makes navigation difficult and increases page load times.
So here is the follow-up page.
What should you post where?
Wishlist threads (#1 #2 #3 #4 #5): bugs and feature requests for Matlab Answers
Frustation threads (#1 #2): frustations about usage and capabilities of Matlab itself
Missing feature threads (#1 #2): features that you whish Matlab would have had
Next Gen threads (#1): features that would break compatibility with previous versions, but would be nice to have
@anyone posting a new thread when the last one gets too large (about 50 answers seems a reasonable limit per thread), please update this list in all last threads. (if you don't have editing privileges, just post a comment asking someone to do the edit)

As an environment for modeling, simulating, and testing dynamic systems, Simulink is used for:

Simulink is now available in a web browser as Simulink Online.

Simulink Online is available to anyone with access to MATLAB Online (see supported license types here) and a Simulink license.

Just sign into MATLAB Online and either start Simulink or open a Simulink model.

Learn more about Simulink Online at the product page on our website.

Simulink Online currently supports the following toolboxes, with more to be added in the future!

  • Simulink
  • Stateflow
  • Simscape
  • Simscape Electrical
  • Simscape Multibody
  • Simulink Control Design
  • DSP System Toolbox

MathWorks gave a perspective on 'Bridging the Technology Readiness Gap with Simulation and Virtual/Remote Testbenches' at the Opal-RT RT20 Panel Session on The Role of Real-Time Simulation in Education. Listen to a recording of the panel session, and also hear perspectives from Quanser, Hydro-Quebec, and RWTH Aachen, by registering for the RT20 conference at the following link .

The EMEA (Europe, Middle East and Africa) Academic Engineering Team are hosting a series of live online webinars every Tuesday and Wednesday. Get up to speed with online teaching and research with MATLAB and access ready-to-use resources.

Watch the introductory video and register here

Where is very courses and how to catch the courses

Hi Everyone,

Require some guidance and pointers on model ee_pmlsm_drive please.

Its regarding a PMSM linear machine model, with a cascade (position and speed) outer loop and a current controller inner loop (Id and Iq currents).

The current Simulink model uses a low voltage DC supply (48v) and uses a step input to the system. My system uses a HV source (400v) and the input is sinusoidal position, with an operating frequency range of 0 to 20hz.

I have used the original model, re-created my own (to learn Simulink/Simscape) with a HV battery source (400v) and used machine parameters that match the application (peer reviewed publication).

As my power electronics background is limited, my background is mechanical, i am unable to tune the inner and outer loops, and am unsure in what order to tune. My project is to use the linear PMSM to drive (motoring) a linear piston for combustion and also use the linear piston to drive the PMSM (generating).

Using the built in PID tuner for the outer speed and position loops i am encountering an error (plant cannot be linearised). I am using a simple 1 hz sine wave to simulate the reference position set-point. With all PID values set to default i have no dq currents, however i have idq ref from the outer velocity controller loop.

Any help with resources and guidance as to how to tune the loops for my updated parameters on this model would be great.

Div Tiwari
Div Tiwari
上次活动时间: 2020-8-21

Moving Lab-based Classes Online

In this article, we discuss how educators can adopt simulation, alternative hardware, and other teaching resources to transition lab-based classes to distance learning: https://medium.com/mathworks/tips-for-moving-your-lab-based-classes-online-1cb53e90ee00.

Do you teach a lab-based class? Please share your thoughts, questions, experience, and feedback on these ideas here. I also welcome you to invite your colleagues to join the discussion here.

One community within MathWorks that has been helping students continue their learning is MATLAB Student Ambassadors. Despite new challenges with transitioning to distance learning, student ambassadors have done a truly amazing job. In a blog that was published recently, I discuss 3 examples of the great things that our student ambassadors have done to aid distance learning. Click here to read the blog. I hope after reading this blog you share my level of admiration for these students.

Student Ambassador at University of Houston hosting a fun and informative virtual event.

hi how to apply single stream into multiple channels in fft simulink simulation from workspace

Sir how can we use Image processing in the Distance Learning

PB75
PB75
上次活动时间: 2020-5-7

LINEAR MOTOR GENERATOR MODEL

Hi, Currently modelling an reciprocating engine coupled to a linear PMSM motor/generator for my PhD. I have downloaded the "Model File Package for Motor Control Design Public Video" simulink model.

Is it possible to convert to rotational PMSM simscape plant model used for a linear PMSM model? As there are none in the library to just drag into the existing control model.

Any ideas i can represent a linear motor based on this existing control model?

My output from the machine needs to be linear position w.r.t, with a total stroke of approximately 100 mm. Can i convert the rotational constant speed input at port "W" to a sinusoidal velocity profile (such that it replicates the velocity profile of a linear machine)?

Any help would be great.

Thanks

I wanted to briefly share my experience in transitioning from a hands-on lab course to a virtual lab in MATLAB. Here at UMass Amherst, Mechanical & Industrial Engineering, we have a required undergraduate lab sequence, one during junior year and another during senior year. I teach the 2nd course, MIE 402, with a focus on measurements, data acquisition, system dynamics, and control.
The main idea behind our labs, in addition to the all too important hands-on experience, is to provide the students with a platform where they can validate and understand limitations of theoretical models from experimental data.
While the hands-on aspect was lost, we were able to create virtual experiments that consisted on Simulink models saved as protected files. In our protected models, students were able to assign input variables, decide on simulation parameters (e.g., integration parameters), and have certain outputs saved to the workspace. The key for making this a challenging lab was twofold: (1) Students were not told about the level of modelling detail inside the protected file (e.g., were dry friction or electrical inductance included?) and (2) each student was assigned a different set of model parameters based on their student ID (via a predefined table inside the protected file). The 2nd point was especially impactful as students felt as if they are working on their own experiment.
We developed virtual labs for a tuned mass damper and a DC motor experiments. Feedback from the students showed that they missed the hands-on experience but really liked being able to interact, as many times as needed, with the virtual lab at their time frame of choice, and have the ability to interact with us (grad assistant and myself) then re-run the experiment to test new ideas.
Some future developments that could significantly enhance the educational impact of such virtual labs would be the addition of real-time animation and increased level of modelling (e.g., data acquisition effects, electromagnetics, etc.’). At UMass we presently do not have access to the entire suite of MATLAB tools, something that prevented us from including these ideas in our virtual labs.
This would have not been possible without Andy Bartlett (tremendous Simulink help) and Div Tiwari (quickly getting us access to required tools).

Professor Martin Trauth has shared lots of teaching resources on his MATLAB Recipes for Earth Sciences site. Now with the changes created by COVID, he's shifting his courses to online, including at-home phone-based data collection. Read how he's doing this and find additional resources: Teaching Data Analysis with MATLAB in COVID-19 Times (Trauth, Potsdam)

A common question you may have when integrating MATLAB Grader into your LMS using the LTI standard is what information is being sent to MATLAB Grader from your LMS?

First, please familiarize yourself with the LTI specification on the IMS Global website: http://www.imsglobal.org/specs/ltiv1p1/implementation-guide

Next, take a look at the documentation we provide on LMS integration that is specific to your platform/vendor: https://www.mathworks.com/help/matlabgrader/lms-integration.html

MathWorks does not require personally identifiable information. More specifically, here are the standard LTI fields that we DO NOT want nor collect, as opposed to what fields we DO collect.

We do NOT want your LMS to send us: - user_image - lis_person_name_given - lis_person_name_family - lis_person_name_full - lis_person_contact_email

We DO require from your LMS: - roles

The other LTI fields listed in the specification are not related to personally identifiable information, and may be required for the LTI session to be launched successfully. For further questions about what is contained in the LTI specification, please refer to the specification and implementation guide provided by IMS, or contact the vendor of your LMS.

can anyone advise which Matlab code I can add to the below codes to have Spectrogram Plot?

OptimalValuesx1y1z1 = [dataArray{1:end-1}];
%% Clear temporary variables
clearvars filename delimiter formatSpec fileID dataArray ans;

re=1;
fs=20e3/re;
datatable=OptimalValuesx1y1z1;
datatable=resample(OptimalValuesx1y1z1,1,re);
%datatable=lowpass(OptimalValuesx1y1z1,10,fs);
datatable(:,2)=datatable(:,2).*0.01;

figure
t=1/fs:1/fs:length(datatable)/fs;
plot(t, rms(datatable(:,2:4)*9.81,3));

ylim([0 10])  
xlim([0 10])
%ylim([0 1])
hold on
%plot(t,ones(1,length(datatable(:,2:4)*9.81))*12,'r--')
xlabel('Time [s]')
ylabel('Amplitude [m/s^2]')
legend('axis X','axis Y','axis Z','limit')

out_mean = mean(rms(datatable(:,2:4),3))
std_mean = std(rms(datatable(:,2:4),3))

% %PSD analysis
figure
x=datatable(:,2:4)*9.81;
nbar = 4;
sll = -30;
win = taylorwin(length(x),nbar,sll);
periodogram(x,win,[],fs);
xlim([0 1.624])
legend('axis X','axis Y','axis Z')
Hafsa Asif
Hafsa Asif
上次活动时间: 2020-4-24

how can i download mathlab

plz tell me the web site where i can easily install mathlab.

G Behery
G Behery
上次活动时间: 2020-4-25

The Corona-virus (COVID-19) detection

I want to use the Image fusions and deep neural network to detect the Corona-virus (COVID-19)

Hello, I want to generate Sinusoidal PWM for 3 level inverter. But I can not finding the way of connect these blocks togather. Is it possible to conenct them? Is there any other way to generate SPWM in simulink?

Hello everyone! I'm trying to find an optimal placement for a recloser using the optimization toolbox. The best place to set a recloser is defined by minimal SAIFI (system average interruption frequency index) value. I've created a little function where Nt - total number of customers, G - are some weights characterizing power lines, Xi - number of interrupted customers (if interruption happens in i-th line AND it has a recloser in it), Mi - row of 1 and 0 (that genetic algorithm should use as a gene I guess...) Here's the code of function:

function [S] = SAIFI_sum (M)
Nt=270;
G = [1.1 1.2 1.3 1.4 1.5 1.6];
X = [270 30 220 180 60 70];
  for i=1:length(M)
      if  M(i)== 1
      N(i) = X(i);
  else
          N(i) = Nt;
      end
  end
  S = 0;
  for j=1:length(M)
      SAIFI(j) = N(j)*G(j);
      S = S + SAIFI(j);
  end
   S
end
As a result I have 51 same results: S = 297 and following message:
"Optimization running.
Objective function value: 297.0
Optimization terminated: average change in the fitness value less than options.FunctionTolerance".
I couldn't understand how to solve this problem.

Created and tested in the university classroom, the Introduction to MATLAB zyBook includes automated assessment using MATLAB Grader. Learn how to create custom MATLAB assignments using zyLabs and provide feedback.

Join this webinar running April 21st and 23rd