Block parameters configuration in Simulink - Mini Project: Build & Apply

Block parameters configuration

📖 Scenario: You are working on a Simulink model to simulate a simple system. To make the model flexible, you want to configure block parameters programmatically.

🎯 Goal: Learn how to create a Simulink model with blocks and set their parameters using MATLAB commands.

📋 What You'll Learn

Create a Simulink model named simple_model

Add a Gain block with a gain value of 5

Add a Constant block with a value of 10

Connect the Constant block output to the Gain block input

Set the Gain block parameter programmatically

Display the configured gain value

💡 Why This Matters

🌍 Real World

Configuring block parameters programmatically helps automate model creation and testing in engineering simulations.

💼 Career

Many engineering and data science roles require automating Simulink models for system design, testing, and optimization.

1

Create a new Simulink model

Create a new Simulink model called simple_model using the new_system command and open it with open_system.

Simulink

# Your code here to create and open the model

Hint

Use new_system('simple_model') to create and open_system('simple_model') to open the model.

2

Add blocks to the model

Add a Gain block named Gain1 and a Constant block named Constant1 to the simple_model using add_block. Position Gain1 at [150 100 200 130] and Constant1 at [50 100 100 130].

Simulink

new_system('simple_model')
open_system('simple_model')
# Your code here to add Gain and Constant blocks

Hint

Use add_block('simulink/Commonly Used Blocks/Gain', 'simple_model/Gain1', 'Position', [150 100 200 130]) to add the Gain block.

3

Set block parameters and connect blocks

Set the Gain block parameter Gain to '5' using set_param. Set the Constant block parameter Value to '10'. Connect the output of Constant1 to the input of Gain1 using add_line.

Simulink

new_system('simple_model')
open_system('simple_model')
add_block('simulink/Commonly Used Blocks/Gain', 'simple_model/Gain1', 'Position', [150 100 200 130])
add_block('simulink/Commonly Used Blocks/Constant', 'simple_model/Constant1', 'Position', [50 100 100 130])
# Your code here to set parameters and connect blocks

Hint

Use set_param to set block parameters and add_line to connect blocks.

4

Display the Gain block parameter

Use get_param to get the Gain parameter value of Gain1 and display it with disp.

Simulink

new_system('simple_model')
open_system('simple_model')
add_block('simulink/Commonly Used Blocks/Gain', 'simple_model/Gain1', 'Position', [150 100 200 130])
add_block('simulink/Commonly Used Blocks/Constant', 'simple_model/Constant1', 'Position', [50 100 100 130])
set_param('simple_model/Gain1', 'Gain', '5')
set_param('simple_model/Constant1', 'Value', '10')
add_line('simple_model', 'Constant1/1', 'Gain1/1')
# Your code here to display the Gain parameter

Hint

Use get_param('simple_model/Gain1', 'Gain') to get the gain value and disp to display it.

Practice

1. What is the main purpose of configuring block parameters in Simulink?

easy

A. To export the block to another model

B. To control how each block behaves during simulation

C. To rename the block automatically

D. To change the color of the block icon

Solution

1. Step 1: Understand block parameters

   Block parameters define the behavior and settings of a block in Simulink.

2. Step 2: Identify the purpose

   Changing parameters affects simulation results, not appearance or export.

3. Final Answer:

   To control how each block behaves during simulation -> Option B

4. Quick Check:

   Block parameters = behavior control [OK]

Hint: Block parameters set behavior, not appearance [OK]

Common Mistakes:

• Confusing parameters with block appearance
• Thinking parameters rename blocks automatically
• Assuming parameters export blocks

2. Which of the following is the correct syntax to set a block parameter named Gain to 5 using set_param?

easy

A. set_param(model/block, 'Gain', 5)

B. set_param('model/block', 'gain', '5')

C. set_param('model/block', Gain, '5')

D. set_param('model/block', 'Gain', '5')

Solution

1. Step 1: Check parameter name and value type

   Parameter names are strings; values must be strings for set_param.

2. Step 2: Validate syntax

   Correct syntax uses quotes around parameter name and value: 'Gain', '5'.

3. Final Answer:

   set_param('model/block', 'Gain', '5') -> Option D

4. Quick Check:

   Parameter and value as strings = correct [OK]

Hint: Always quote parameter names and values in set_param [OK]

Common Mistakes:

• Passing numeric value without quotes
• Using wrong case in parameter name
• Omitting quotes around parameter name

3. Given the code snippet:

set_param('myModel/GainBlock', 'Gain', '10');
value = get_param('myModel/GainBlock', 'Gain');

What will be the value of value after execution?

medium

A. 10

B. Gain

C. '10'

D. Error

Solution

1. Step 1: Understand set_param effect

   set_param sets the 'Gain' parameter to string '10'.

2. Step 2: Understand get_param return type

   get_param returns parameter values as strings, so value is "10" (string without quotes in output).

3. Final Answer:

   "10" -> Option A

4. Quick Check:

   get_param returns string value [OK]

Hint: get_param returns parameter values as strings [OK]

Common Mistakes:

• Assuming get_param returns numeric value
• Confusing parameter name with value
• Expecting error from correct syntax

4. Consider this code:

set_param('model/Integrator', 'InitialCondition', 0);

What is the error in this code?

medium

A. Value 0 should be a string '0'

B. Parameter name 'InitialCondition' is incorrect

C. No error

D. Block path 'model/Integrator' is invalid

Solution

1. Step 1: Check parameter value type

   set_param accepts numeric values for InitialCondition; 0 is converted to '0'.

2. Step 2: Confirm parameter name and block path

   'InitialCondition' is valid; block path assumed correct.

3. Final Answer:

   No error -> Option C

4. Quick Check:

   set_param handles numeric values [OK]

Hint: set_param accepts numeric values directly [OK]

Common Mistakes:

• Assuming value must be quoted string
• Thinking parameter name is wrong
• Believing block path is invalid

5. You want to programmatically change the 'Gain' parameter of multiple Gain blocks in a model named controlModel. Which approach correctly updates all Gain blocks to value 3.5?

hard

A. Use find_system to get all Gain blocks, then loop with set_param setting 'Gain' to '3.5'

B. Manually open each block and set 'Gain' to 3.5 in the GUI

C. Use set_param('controlModel', 'Gain', '3.5') to set all blocks at once

D. Rename all Gain blocks to '3.5' using set_param

Solution

1. Step 1: Identify all Gain blocks

   Use find_system('controlModel', 'BlockType', 'Gain') to get all Gain blocks.

2. Step 2: Loop through blocks and set parameter

   For each block, use set_param(block, 'Gain', '3.5') to update the parameter.

3. Final Answer:

   Use find_system and loop with set_param to update all Gain blocks -> Option A

4. Quick Check:

   find_system + loop + set_param = bulk update [OK]

Hint: Use find_system to select blocks, then set_param in loop [OK]

Common Mistakes:

• Trying to set parameter on model instead of blocks
• Not quoting numeric values in set_param
• Renaming blocks instead of changing parameters