How to connect value in app designer to simulink

I have Simscape Simulink Model. I set the parameter of Spring Stiffness is k, Mass is m.

How to add value from Appdesign and Simulink ?

Thank you!

Answer 1

[Samay Sagar]

Hi Thai,

I understand that you want to pass values for certain parameters (spring stiffness and mass) from a MLAPP to a Simulink model. Here is how you can create such an app:

1. Create an MLAPP with input fields for “k” and “m”. These could be numeric edit fields or sliders, depending on your preference.
2. Add a button to the app that, when clicked, will run the simulation with the specified parameters.
3. Create a callback function for the button to update the parameters using “set_param”. Here is an example of how you might implement this:

function UpdateParametersButtonPushed(app, event)
    % Retrieve parameter values from the app
    k_value = app.SpringStiffnessEditField.Value;
    m_value = app.MassEditField.Value;
    
    % Set the parameters in the Simulink model
    % Replace 'YourSpringBlock' and 'YourMassBlock' with the actual block paths
    set_param('spring_mass_model/YourSpringBlock', 'Stiffness', num2str(k_value));
    set_param('spring_mass_model/YourMassBlock', 'Mass', num2str(m_value));
    
    % Run the simulation
    simOut = sim('spring_mass_model', 'SimulationMode', 'normal');
    
    % Extract the results if needed   
    time = simOut.tout;
    outputs = simOut.yout{1}.Values.Data;
end

Alternatively, you can also configure your model to take the parameter values from the base workspace. In the above callback function, you can use “assignin” to update the corresponding variable as follows:

assignin('base', 'mass', m_value);

Ensure that the corresponding blocks take these values as variables from the workspace by specifying the same names in the block parameters.

If you want to pass input signals to your model from your app, you can refer the following documentation to prepare your input data:

https://www.mathworks.com/help/releases/R2021a/simulink/ug/insert-and-edit-signal-data.html

For more information about “set_param” and “assignin”,you can refer the following documentation:

https://www.mathworks.com/help/releases/R2021a/simulink/slref/set_param.html

https://www.mathworks.com/help/releases/R2021a/matlab/ref/assignin.html