Toggle Side Panel
Close search
Table of Contents
5-CH IR Line Sensor Array
PictoBlox Block

Set PID Constants

Description

This block configures the three constants used by the PID controller.

Constant Description
Kp – Proportional Determines the correction based on the current line-position error.
Ki – Integral Corrects persistent errors accumulated over time.
Kd – Derivative Responds to changes in error to reduce oscillation and overshooting.

How It Works

The robot calculates how far the detected line is from the centre of the sensor array.

The PID controller uses the configured constants to determine the required steering correction and adjusts the motor speeds accordingly.

Python Function – Quarky and Quarky Intellio:

lf5ir.setpidconstants(0.6, 0.0, 0.9)

Example: Set Kp = 0.6, Ki = 0.0, and Kd = 0.9 to configure the PID controller using the values shown in the block.

These are example values and may need adjustment depending on the robot and track.

Understanding PID Control

Proportional (P): Responds to the current line-position error. A larger error produces a stronger correction.

Integral (I): Accumulates errors over time to help correct persistent drift.

Derivative (D): Responds to changes in the error to reduce sudden corrections and improve stability.

Recommended PID Tuning

  1. Begin with Ki and Kd set to 0, using a moderate Kp value.
  2. Increase Kp gradually if the robot corrects too slowly.
  3. Decrease Kp if the robot oscillates excessively.
  4. Introduce Kd to reduce overshooting and improve stability.
  5. Add a small Ki value only if the robot continues to drift consistently towards one side.

Note: Test the robot at a low speed while adjusting PID parameters.

Example

There are no examples documented for this article.
PictoBlox Extensions
  1. Scratch Based Default Extensions
    1. Motion
    2. Looks
    3. Sound
    4. Control
    5. Sensing
    6. Operators
    7. My Blocks
    8. Variables
  2. Artificial Intelligence
    1. Face Detection
    2. Object Detection
    3. Human Body Detection
    4. Computer Vision
    5. Text Recognition
    6. Speech Recognition (Old)
    7. ChatGPT
    8. Natural Language Processing
    9. Recognition Cards
    10. Text to Speech
    11. Translate
    12. Open CV
  3. Innovative Extensions
    1. Graph Extension
    2. Content Creation Extension
    3. Animated Text Extension
    4. QR Code Scanner
    5. Weather Data
    6. Physics Engine
    7. IFTTT Webhooks
    8. Internet of Things (IoT)
    9. Data Logger
    10. Music
    11. Video Sensing
    12. Pen
  4. Machine Learning Environment
    1. Image Classifier (ML)
    2. Object Detection (ML)
    3. Pose Classifier (ML)
    4. Hand Pose Classifier (ML)
    5. Audio Classifier (ML)
    6. Number Classifier and Regression (ML)
    7. Text Classifier (ML)
  5. Quarky
    1. Quarky Intellio I2C Communication
    2. Quarky Advance Sensors Extension
    3. Quarky Connect
    4. Display (Quarky)
    5. Quarky (Main)
    6. Robot (Quarky)
    7. Sensors (Quarky)
    8. Speaker (Quarky)
    9. Quarky Ultimate Robots
    10. Quarky Expansion Board
    11. Mars Rover
    12. Humanoid (Quarky)
    13. Quadruped (Quarky)
    14. IoT House (Quarky)
    15. Quarky Mecanum
    16. Quarky Robotic Arm
    17. Dabble
    18. Quarky Advance Line Following