Robotics Programming: PID Algorithm - Wall Following and Balancing

Today's episode of Robotics Programming is a special one, we will learn how to write a PID or Proportional, Integral and Derivative controller. In this complete guide to understanding PID we will breakdown the Mathematics, give step by step examples and see it in use! We will apply it to solve problems in robotics by showing how it can be applied to create both a wall following robot and a balancing / standing one.

This versatile algorithm is a staple not just in robotics programming but in many engineering disciplines and is the go-to method so solve many problems. We will discuss each of the 3 components of the PID controller, there relationship to each other and the overall outcome and introduce the idea of tuning a PID controller. Using a handwritten problem and also how to implement a PID in C for Arduino helps visualize solving this problem.

The PID algorithm can look intimidating to the uninitiated, but it is actually just 3 simple math equations summed together. Proportional is simply multiplication, Integral maintains a running total, and Derivative subtracts to obtain the difference of the error from the previous time the algorithm ran.

Throughout this series we will be introducing topics on building and programming an autonomous mobile robot! You can follow along with each lab adding amazing new behaviors to you robot projects and learning the algorithms and tuning techniques that produce incredible robots! We will be exploring reactive algorithms such as PID, Potential Fields and A*. Along the way you will learn how to program behaviors such as object following, wall following, standing / balancing, go-to goal and object avoidance. This series is intended to allow you to follow along with your own robot.

Code access: Direct access to source code and additional resources are available by becoming a Coding Coach supporter. You can join and learn more here: https://codingcoach.net/sponsor . You may also copy the code from the video as you follow along.

This video series is meant to help anyone interested in programming robots follow along. You do not need to use the same robot as I do. Any mobile robot can run these same algorithms, you just have to tune the robot differently.

If you missed episode 1, you can find it here:    • Robotics Programming: Building an Autonomo...  
Episode 2:    • Robotics Programming: Ultrasonic Sensor | ...  
Episode 3:    • Robotics Programming: Servo Control for Ar...  
Episode 4:    • Robotics Programming: Servo and HC-SR04 Ul...  

The next video in this series will be arriving shortly, make sure to subscribe and ring the bell to be notified when it lands!

Playlist of the full series:    • Robotics Programming Labs  
Video that discusses the future direction of the series:    • Robotics Programming: Introducing Henry IX...  

Chapters:
0:00 Introduction
1:35 Control Systems
4:32 How to determine Error and Magnitude
8:25 Applying a PID Controller
9:20 PID Overview
11:48 Proportional
13:30 Integral
15:21 Derivative
16:09 Example PID Problem
28:09 Coding a PID
31:45 Conclusion
32:46 Outtakes

#codingcoach #arduinorobot #PID

Robot used
Pololu 3pi+: https://www.pololu.com/category/280/3...

Links to hardware: (Amazon Affiliate links)
S90 9g Servo (10 pack): https://amzn.to/3tmUhGN
Mini breadboards: https://amzn.to/2NeHXZA
Jumper Wire assortment: https://amzn.to/3bJD6Jh
470uf Capacitors: https://amzn.to/2ORqBSU
Break-away headers: https://amzn.to/3cwVapl

Other robots, batteries and tools
Elegoo Smart Car: https://amzn.to/3iG3uFO
Robot car chassis (with encoder cutout): https://amzn.to/3odlacY
Pololu Zumo: https://amzn.to/39TbaAC

Batteries:
EBL Rechargeable batteries: https://amzn.to/3pdiM7A

Micrometer Caliper Measuring Tool (To measure wheel diameter): https://amzn.to/3sQ0BqB