Educational PID Demonstration

A visual representation of Control System application: a moving arm.

info

Author: Gabriela-Florentina Alexa
GitHub Project Link: https://github.com/UPB-PMRust-Students/project-Eiline04

Description

The project I am about to make has the purpose of illustrating PID principles, using an ESP32 WROOM to balance a fan-powered arm. The system consists of a distance sensor used to follow the hand of the user. For educational purposes, I am also going to use a gyroscope in order to get stability feedback. Furthermore, the fan is moved with a brushless motor (which is connected to the microcontroller via an ESC - electronic Speed Controller). Thus, this project has a high impact on demonstrating how a real-time control system works.

Motivation

My interest in PID control began in high school, when I first used it to optimize the trajectory of an autonomous robot (as I was part of a robotics team). Since then, I've been fascinated by how control systems are applied in everyday life-whether in cars, drones, or even household appliances like thermostats. This project allows me to dive deeper into a topic I find both intellectually challenging and personally rewarding. By combining sensors, real-time feedback, and control algorithms, I aim to better understand and illustrate the principles behind modern automation. I am excited to help the 16 y.o. version of me understand the 'magic' behind the programming tools she had used in high school, but also create a visual representation of a very cool principle, so that others can understand it too.

Architecture

The architecture of the system is designed to demonstrate PID control principles in a real-time environment. The main components of the architecture are:

• Sensor System: A distance sensor detects the user's hand position, acting as the system input.
• Controller: An ESP32 WROOM microcontroller runs the PID algorithm and processes data from the sensors (gyro and distance sensor).
• Feedback System: A gyroscope provides real-time orientation data for stability feedback. It will also provide data that can be used to draw informative graphics.
• Actuator System: A brushless motor, connected to the ESP32 via an ESC (Electronic Speed Controller), adjusts the fan's thrust to balance the arm.
• Power Supply: Delivers sufficient current (~20A) to drive the motor. (It has bult-in off swith in case of danger)
• Cooler: Makes sure the ESC is not overheating (althought it is very unlikely to heat, as I am going to use 20-30A).

These components are interconnected to form a closed-loop control system that continuously adjusts the fan thrust to maintain balance (to keep the arm at a constant position) based on the data provided by the distance sensor.

Log

Week 5 - 11 May

Week 12 - 18 May

Week 19 - 25 May

Hardware

Hardware

The project uses the following hardware components:

• ESP32 WROOM: Core microcontroller for real-time PID control logic.
• VL53L0X Distance Sensor: Detects the position of the user's hand (I²C).
• MPU6050 Gyroscope: Provides angular velocity and acceleration data for stability feedback (I²C).
• Brushless Motor (BLDC) + ESC (Electronic Speed Controller): Acts as the actuator that drives the fan to balance the arm, controlled via PWM from the ESP32.
• Cooler (Fan): Controlled via a GPIO pin to prevent overheating.
• Power Source (12V / 20A): Powers the ESC -> brushless motor.
• Physical Frame (wood/cardboard): Holds all components and supports the motion of the balancing arm.

Components and materials - Photos

Schematics

Bill of Materials

Device	Usage	Price
ESP32 WROOM Dev Board	Main microcontroller	40.00 RON
GY-521 (MPU6050)	Gyroscope and accelerometer module	24.16 RON
VL53L0X Time-of-Flight Sensor	Measures distance to user's hand	16.76 RON
ESC 30A	Controls brushless motor	47.15 RON
Brushless Propeller Set 6045 CW/CCW	Attached to motor for thrust	9.84 RON
Brushless Motor (BLDC)	Keeps the hand in needed position.	45 RON
5V Fan (Raspberry Pi, 3030)	Used as a cooler	8.04 RON
4mm Banana Connector (Female, Red) x3	Power connection	5.22 RON
4mm Banana Connector (Female, Black) x3	Ground connection	5.22 RON
4mm Banana Connector (Male, Red) x3	Power cable end	2.94 RON
4mm Banana Connector (Male, Black) x3	Ground cable end	2.94 RON
[Hinge](physical shop)	Makes the arm mobile.	8 RON

Total estimated cost: ~215 RON

Software

Library	Description	Usage
embassy-rs	Asynchronous embedded framework	Handles async tasks on the ESP32
esp-idf-sys	Rust bindings for ESP-IDF	Enables low-level interaction with ESP32
i2cdev	I2C device communication	Communicates with distance sensor and gyroscope
pwm	Pulse Width Modulation	Controls ESC for motor speed
serialport	Serial communication	Debugging and data logging

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Links

1. PID Explained – Useful introduction to PID control.
2. Idea – From here I have the project idea.
3. ESP32 & BLDC Motor – Useful tutorial.