Robocon Recruitments- Task 3.2

Solution for Subtask A: Mastering PID Control

• A PID controller is a powerful tool that uses proportional, integral, and derivative terms to control a system. By mastering this tool, you'll be able to control the robot with precision and accuracy.

  • You can learn more about PID controllers from these resources: https://youtu.be/wkfEZmsQqiA and any other content you find for pid controllers.

• To get started:

  • You'll need to use the Atom bot package again. (You may use another bot, but this guide shall follow the atom bot).
  • In this repository, there's a file called pid.py. This file needs to be placed in Robotics_ws/src/atom/script.
  • Once the file is in place, you need to run chmod +x on it to make it executable.
  • Then, in the original folder (Robotics_ws), you need to run catkin_make and source devel/setup.bash.
  • Finally, you can run rosrun atom pid.py for the script to start working. Make sure you first launch the world using the command from Task 1 (roslaunch atom world.launch).

• The pid.py script has some boilerplate code for implementing a PID controller. Currently, it asks you to enter an input velocity every 2 seconds. You need to modify this file so that it asks for coordinates instead and the bot must reach those coordinates using PID control.

• To control the bot's movement, you can use the odom topic to get its current status and the cmd_vel topic to give it new velocities. Just be careful not to give it large velocities or it might behave unpredictably.