Simulink App Designer Tutorial

Simulink App Designer is a powerful tool within MATLAB for creating custom graphical user interfaces (GUIs) and applications. In this tutorial, we will cover the essentials of getting started with Simulink App Designer, including how to design, develop, and test your applications. We will also explore how to integrate various Simulink components and create interactive features for a fully functional app. By the end of this guide, you will have a solid understanding of the basics of App Designer and be able to create your own simple applications.

Introduction to Simulink App Designer

Simulink App Designer is a comprehensive environment for designing and deploying interactive applications within the MATLAB and Simulink ecosystem. It provides a user-friendly interface that allows users to create custom apps with a drag-and-drop approach, without needing extensive programming knowledge. This tool is particularly useful for engineers and scientists who want to build custom interfaces for their simulations, data analysis, or system designs.

Getting Started with App Designer

1. Opening App Designer
   To start using Simulink App Designer, open MATLAB and navigate to the Apps tab. Click on the "App Designer" icon to launch the environment. You will be greeted with a new, blank app canvas where you can begin designing your user interface.

2. Designing the User Interface
   The App Designer interface consists of two main parts: the Design View and the Code View. In the Design View, you can drag and drop various UI components such as buttons, sliders, and text boxes onto the canvas. You can customize these components using the Property Inspector, where you can set properties like size, position, and appearance.

   Key Components:

   • Button: Used to trigger actions or events.
   • Slider: Allows users to select a value from a range.
   • Text Box: Used for user input or displaying text.
   • Axes: Provides a space for plotting graphs and visualizing data.

   For example, to add a button to your app, simply drag the Button component from the Component Library onto the canvas. You can then set its label and other properties using the Property Inspector.

3. Adding Interactivity with Callbacks
   Interactivity in App Designer is managed through callbacks. Callbacks are functions that execute in response to user actions, such as clicking a button or changing a slider value. To add a callback, select the component you want to make interactive, go to the Code View, and write the corresponding callback function.

   For instance, if you have a button that should display a message when clicked, you can create a callback function like this:

   matlab
   % Button pushed function: Button
   function ButtonPushed(app, event)
       uialert(app.UIFigure, 'Button was clicked!', 'Notification');
   end
   

   This function uses uialert to show a message box when the button is clicked.

Integrating Simulink Components

One of the powerful features of App Designer is the ability to integrate Simulink models into your application. You can use App Designer to control and interact with Simulink models directly from your custom GUI. Here’s how you can do this:

1. Loading a Simulink Model
   To integrate a Simulink model, first, load your Simulink model into MATLAB. For example, if you have a model named myModel.slx, load it using:

   matlab
   load_system('myModel');
   

2. Creating a Simulink Block in App Designer
   You can interact with Simulink blocks through MATLAB code in your app. For instance, if you want to start a simulation when a button is clicked, you can write a callback function that uses the sim command:

   matlab
   % Button pushed function: StartSimButton
   function StartSimButtonPushed(app, event)
       sim('myModel');
   end
   

   This function triggers the simulation of the model when the button is clicked.

3. Displaying Results
   To display simulation results in your app, you can use UI components like axes to plot data. For example, after running a simulation, you might want to plot the results in an axes component:

   matlab
   % Button pushed function: PlotButton
   function PlotButtonPushed(app, event)
       simOut = sim('myModel');
       plot(app.UIAxes, simOut.tout, simOut.yout);
   end
   

   Here, simOut.tout and simOut.yout are time and output data from the simulation that you plot on the app’s axes.

Testing and Deploying Your App

1. Testing the App
   To test your app, simply click the "Run" button in App Designer. This will open your app in a new window where you can interact with it and verify that all components and callbacks work as expected. Make sure to test all possible user interactions to ensure the app behaves correctly.

2. Deploying the App
   Once you are satisfied with your app, you can deploy it by packaging it as a standalone application or sharing it with others. App Designer provides options to export your app as a MATLAB app file (.mlapp) or as a standalone executable (.exe) if you have MATLAB Compiler.

Conclusion

Simulink App Designer is a versatile tool that allows users to create custom applications with ease. By following this tutorial, you have learned how to design user interfaces, add interactivity, integrate Simulink models, and test and deploy your applications. With these skills, you can develop powerful custom tools for simulation, data analysis, and more.

Summary

• App Designer enables the creation of custom GUIs within MATLAB.
• Design View allows drag-and-drop UI component placement.
• Code View is used to write callbacks for interactivity.
• Simulink Integration allows interaction with models and plotting results.
• Testing and Deployment ensure the functionality and distribution of your app.

With practice, you will be able to leverage the full capabilities of Simulink App Designer to create sophisticated and user-friendly applications.