Week -2

1.)

Simulink Model Setup

1. Open Simulink:

   • Launch MATLAB and open Simulink.

2. Create a New Model:

   • Go to File > New > Model.

3. Add the Components:

   • Battery: Use a DC Voltage Source block.
   • Switch: Use a Switch block (or a Manual Switch).
   • Solenoid: Use a Simscape block for a solenoid or a custom force block that simulates the plunger's motion.
   • Bell: Represent this as a simple mechanical block that receives input from the solenoid (this could be a spring or mass block).

Parameters

Assume the following parameters for the components:

• Battery Voltage: $V = 12 \, \text{V}$V=12V
• Switch Timing: The switch will be closed for $t = 2 \, \text{s}$t=2s.
• Solenoid Force: Adjust parameters to simulate the pull of the solenoid (e.g., a force of $5 \, \text{N}$5N).
• Plunger Mass: $m = 0.1 \, \text{kg}$m=0.1kg (this can be adjusted based on desired behavior).

Model Steps

1. Battery Configuration:

   • Add a DC Voltage Source block and set it to $12 \, \text{V}$12V.

2. Switch Configuration:

   • Add a Manual Switch or Switch block. Connect it to the battery and solenoid.
   • To automate the switch for 2 seconds, you can use a Pulse Generator or Signal Builder block to control the switch state.

3. Solenoid Configuration:

   • Use a Simscape block representing the solenoid or create a custom model with a force acting on the plunger based on the battery voltage.
   • Connect the output of the switch to the solenoid input.

4. Mechanical Setup:

   • Add a Mass block to represent the plunger.
   • Add a Spring and Damper block if you want to model the physical properties of the plunger mechanism.

5. Output:

   • Use a Scope block to visualize the movement of the plunger over time.
   • Connect the output of the plunger (or force) to the scope to observe its behavior.

Sample Connections

• DC Voltage Source → Manual Switch → Solenoid.
• Solenoid → Mass (Plunger).
• Mass → Scope to observe displacement/velocity.

Running the Model

1. Set the Simulation Parameters:

   • Go to Simulation > Model Configuration Parameters.
   • Set the stop time to $5 \, \text{s}$5s to observe the plunger movement after the switch is released.

2. Run the Simulation:

   • Click the Run button to simulate the model.

3. Observe the Output:

• Open the Scope to view how the plunger moves when the switch is closed for 2 seconds.

2.)

Simulink Model Setup

1. Open Simulink:

   • Launch MATLAB and open Simulink.

2. Create a New Model:

   • Go to File > New > Model.

3. Add Components:

   • Temperature Source: Use a Signal Builder or Step block to generate the temperature profile.
   • Thermistor: This can be represented simply by a transfer function or a sensor block that outputs the current temperature.
   • Fan Control Logic: Use a Switch block to turn the fan ON/OFF based on the temperature.
   • Fan Model: Use a Scope to visualize the fan state (ON/OFF).

Step-by-Step Configuration

1. Create the Temperature Source

• Signal Builder Block:

  • Drag a Signal Builder block from the Simulink library.
  • Set it to output the following temperatures:
    • From $0$0 to $10$10 seconds: $20^\circ C$20∘C
    • From $10$10 to $30$30 seconds: $27^\circ C$27∘C
    • From $30$30 to $50$50 seconds: $23^\circ C$23∘C

  You can set the points in the Signal Builder as follows:

  • (0, 20)
  • (10, 20)
  • (10, 27)
  • (30, 27)
  • (30, 23)
  • (50, 23)

2. Add the Thermistor

• The thermistor can be represented as a simple output from the temperature source. Just connect the output of the Signal Builder directly to the input of the switch.

3. Add Fan Control Logic

• Switch Block:
  • Drag a Switch block from the Simulink library.
  • Set the threshold of the switch to $25^\circ C$25∘C to determine whether the fan should be ON or OFF.
  • Connect the output of the temperature source to the first input of the Switch block.

4. Configure the Fan Output

• Fan State:
  • For the second input of the switch, connect a constant block set to $0$0 (OFF) and a constant block set to $1$1 (ON) for the fan.
  • Use a Scope to visualize the output of the Switch block, which will show the fan state (1 for ON, 0 for OFF).

5. Connect the Blocks

• Connect the output of the Signal Builder to the first input of the Switch block.
• Connect the second input of the Switch to the constant blocks (0 and 1).
• Connect the output of the Switch to a Scope block to visualize the fan state.

6. Set Simulation Parameters

• Go to Simulation > Model Configuration Parameters.
• Set the stop time to 50 seconds.

7. Run the Model

• Click the Run button to simulate the model.
• Open the Scope to observe the fan's state over time based on the temperature profile.

Saving the Model in Previous Version

1. Save the Model:

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

2. Convert to Previous Version:

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