Week - 4

1.)

Example Stateflow Logic

Here's how you might structure your states and transitions in Stateflow:

• States:
  • Inactive:
    • On Entry: LED_power = 0;
  • Power On:
    • Transition to Check Water Supply.
  • Check Water Supply:
    • If water_supply == 1 then transition to Soaking.
    • Else transition to Inactive and activate the water supply LED: LED_water_supply = 1;
  • Soaking:
    • On Entry: duration = 200;
  • Washing:
    • On Entry: duration = 100;
  • Rinsing:
    • On Entry: duration = 20;
  • Drying:
    • On Entry: duration = 50;
  • Finished:
    • On Entry: LED_finished = 1;

Connecting Outputs to Simulink

8. Connect Stateflow Outputs:
   • Connect the LED outputs to Simulink blocks (e.g., Scope or Display) to visualize the states of the LEDs.

Finalize and Test the Model

9. Set Up Simulation Parameters:

   • Go to Simulation > Model Configuration Parameters.
   • Set the stop time to a value that exceeds the total duration of the processes (e.g., 500 seconds).

10. Run the Simulation:

• Click the Run button to simulate the washing machine logic.
• Check the outputs to ensure that the LEDs and transitions work as expected.

2.)

Steps to Create the Gear Shift Logic in Simulink

1. Open Simulink and Create a New Model:

   • Launch MATLAB and open Simulink.
   • Go to File > New > Model.

2. Add a Stateflow Chart:

   • From the Simulink Library Browser, drag a Stateflow block into your model.

3. Open the Stateflow Chart:

   • Double-click the Stateflow block to open the Stateflow editor.

Define States and Logic

4. Create States for Gear Shifting:

   • You can represent the gear shifting logic using a single state since the gear is directly dependent on the input speed. You will use a conditional structure (a single chart) to determine the current gear based on the input speed.

5. Add Input and Output:

   • Create an input variable speed to take the speed input.
   • Create an output variable gear to display the gear number.

Implement Gear Shifting Logic

6. Add Gear Shifting Logic: In the Stateflow editor, define the logic using MATLAB-like syntax in the action of the state. Here’s how you can structure it:

plaintext
// Transition logic based on speed
if (speed >= 0 && speed <= 15) {
    gear = 1;
} else if (speed >= 16 && speed <= 25) {
    gear = 2;
} else if (speed >= 26 && speed <= 40) {
    gear = 3;
} else if (speed >= 41 && speed <= 60) {
    gear = 4;
} else if (speed > 61) {
    gear = 5;
} else {
    gear = 0; // For any negative speed, gear could be 0 or indicate error.
}

7. Create the Output Display:
   • Connect the output variable gear to a Display block or a Scope in your Simulink model to visualize the current gear number.

Add Speed Input

8. Add a Constant or Slider Block for Speed Input:
   • To provide the speed input during the simulation, you can use a Slider Gain block or a Constant block (for initial input) and connect it to the speed input of the Stateflow chart.

Finalize and Connect Components

9. Connect All Components:
   • Connect the Slider Gain or Constant block to the Stateflow block input (speed).
   • Connect the Stateflow block output (gear) to a Display block to visualize the gear number.

Set Simulation Parameters

10. Set Up Simulation Parameters:
    • Go to Simulation > Model Configuration Parameters.
    • Set the stop time for the simulation to a value that allows you to test gear shifting (e.g., 60 seconds).

Run the Simulation

11. Run the Model:
    • Click the Run button to start the simulation.
    • Adjust the speed using the slider (or observe the output if using a constant) and watch the gear number change according to the speed input.

Saving the Model in Previous Version

12. Save the Model:

    • Go to File > Save As.
    • Choose a name for your model.

13. Convert to Previous Version:

    • Go to File > Save As.
    • Select Previous Version.
    • Choose R2021a or any lower version.