I am trying to run a PID controller (another model in simulink) using sim command in a matlab function block.
However it takes long iteration, seems to be that the matlab function block need more time.
How to get faster result?
Here is my code in matlab function block:
function [Kpp,Kii,Kdd] = fcn(u)
coder.extrinsic('sim');
sim('ExternePID'); %call out to ExternePID model
Don't do that, that won't work. Instead include your second Simulink model as a referenced model in your top-level Simulink model. This way, both models can run concurrently.
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I have a simulink file and I'm working on designing a controller.
The file contains several electronics converters connected in parallel and each converter has a controller. The converter measures voltage and current and pass them to the controller to control.
The simulink file generates the simout file after simulation and that simout file is being used to calculate the impedance of the electrical grid in a m script file as a transfer function. I need to use the transfer function of impedance from the workspace in the place of " Req +sLeq" as in the purple marked position of the picture.
In other words, in my controller design, I need to call that m-file transfer function into a block and use the transfer function (impedance) as active damping during the simulation.
I'm not sure how can I call the transfer function from the m file (generated from simout) back to the simulink block during simulation.
The simulation need to be done in one go as closed loop system.
Please help me for this.
I can think of two ways to solve this. First, you can try to use a Matlab function block:
https://www.mathworks.com/help/simulink/slref/matlabfunction.html
Otherwise, you can always split your routines. Split your simulations, obtain your transfer function -which now exists in the workspace- then run your control system simulation using a separate file.
Dummy main-file
simOut = sim('electricalSimulation'); % Your first simulation
output = simOut.output;
input = simOut.input;
electricalTf = obtainTF(output, input); % Your identification routine
sim('completeSystem');
I got a script from this link and it runs correctly in MATLAB. However, when I create a Simulink model, it runs normally, but I can get the data from m file.
MATLAB script:
function data = Loadcell()
eml.extrinsic('arduino','addon','read_HX711')
a = arduino('COM5','Mega2560','libraries','ExampleAddon/HX711');
while 1
LoadCell = addon(a, 'ExampleAddon/HX711',{'D2','D3'});
data = read_HX711(LoadCell)
end
end
Simulink function
function data = Loadcell()
coder.extrinsic('Loadcell');
Loadcell = zeros('double');
data = zeros('double');
data = Loadcell
end
I run Simulink in external mode using Arduino and I don't get the data from that code. How can I use that MATLAB script to use it in the Simulink block model and get the data?
It's most likely a couple of issues
naming your Embedded MATLAB function in Simulink the same as the MATLAB function. (How would you expect Simulink to know which function it's supposed to call? The MATLAB function, or re-entering the Embedded MATLAB function?)
defining Loadcell as an extrinsic function, then (re)defining it to be a double 0.0, then trying to execute it as a function.
I suspect you want something like,
function data = Loadcell_Wrapper()
coder.extrinsic('Loadcell');
data = zeros(1,1,'double');
data = Loadcell()
end
(Also, not part of your question, but isn't there an infinite loop in the MATLAB code?)
I have a simulink file, where I need to call a certain optimization function:
function u = MPC(r, x0, Thorizon, Q, W, cons)
R = [];
for s=1:Thorizon+1
R = vertcat(R, r);
end
ops = sdpsettings('solver','quadprog','verbose',0);
U = sdpvar(Thorizon+1,1);
cost = (R - (Q*U+W*x0))'*(R-(Q*U+W*x0))+U'*U;
optimize(cons,cost,ops);
u = value(U);
u = u(1);
end
However, I'm not sure how to implement this in Simulink.
I tried it with a matlab function block, but a couple of problems arise.
First of all, it returns some errors like
Function 'eval' is not supported for code generation. Consider adding
coder.extrinsic('eval') at the top of the function to bypass code
generation.
or like
Function 'sdpsettings.m' (#103.12741.12757), line 355, column 12:
"temporaryOptions" Launch diagnostic report.
It has (probably) to do with the fact that the optimizer (sdp) is an external function, one that is part of a seperately installed library.
The other possible issue, is one with the input arguments.
If I were to use a Matlab function block, there would be a problem with the cons argument, one that can take inequality forms, like
U<1
The function, does however, work in the Matlab environment itself.
But the output of this function, needs to be the input of a continuous non-linearm model present in simulink.
So my question is,
are there any suggestions, to either: Make such function in Simulink work, like via a Matlab function block, or use the function in the matlab runtime environment itself, and send the output value repeatedly to the simulink model?
I have trained the neural network in matlab script file and saved the trained data into a .mat file. So that after loading the .mat file in Simulink user defined functions, I could use this trained data to test the inputs.
But I get run time error
Call to Matlab function aborted: Error calling Matlab function 'sim'. Press OK to open the debugger.
and in debugger the error is
MATLAB Function Interface Error: Error calling MATLAB function 'sim'. Block Neural Network Function (#108) While executing: none
The code is as
function [tau1p,tau2p] = Nntwork(theta1,theta1d,theta2,theta2d,theta1dd,theta2dd)
coder.extrinsic('load');
coder.extrinsic('sim');
net=load('trainednet.mat');
a=zeros(1,2);
a=sim(net,[theta1;theta1d;theta1dd;theta2;theta2d;theta2dd]);
if some one could help me to resolve this error.
The first thing I'd check is that your variable net is actually a NN object. The syntax that you are using for load loads all variables in the mat file into a structure called net, and you most likely need to use net.net to extract the net variable from the net structure. (Of course if that's the case then you shouldn't call the structure (i.e. the output from load) net as it will be very confusing.
However, I'd suggest the best way to do this is to wrap you code into another function, and call that function from the MATLAB Function Block. i.e.
Make the MATLAB function block something like:
function [tau1p,tau2p] = NntworkWrapper(theta1,theta1d,theta2,theta2d,theta1dd,theta2dd)
coder.extrinsic('Nntwork');
a=zeros(1,2);
a=Nntwork([theta1;theta1d;theta1dd;theta2;theta2d;theta2dd]);
Then have this additional function in a separate m-file:
function a = Nntwork(theta_data)
load('trainednet.mat');
a=sim(net,theta_data);
A set-up like that will enable you to run and test the NN code independently of Simulink, but also call it from Simulink when required.
I am building a reduced order observer in MATLAB. The matrices are calculated using functions/script files outside matlab and simulink function blocks are using these functions to calculate values.
The problem is that some commands like 'acker', 'place' etc which used to work on command window/function/script files are not working in simulink function block and showing errors.
I tried using simin block to take these matrices from workspace but it is also showing errors which I can't understand.
Thanks for your help.
If I get your question correctly then, from User defined functions, you could add a Matlab function block with the following code:
function fcn(in)
%#codegen
coder.extrinsic('acker', 'place')
# Now you can use acker, place so add more code.