Project Overview

This project introduces students to controlling a DC motor using an L298N motor driver module and an ESP32 microcontroller. The project will help students understand how microcontrollers interface with higher-power components using drivers, and how PWM signals affect motor speed.

Educational Goals

• Learn how to control motor direction and speed using GPIO and PWM
• Understand the role of a motor driver and H-bridge
• Write MicroPython code to drive and reverse motor rotation
• Explore real-world applications such as robotic wheels and conveyor belts

Detailed Parts List

• 1x ESP32 Dev Board (36-pin)
• 1x L298N Motor Driver Module
• 1x DC Motor (6V–12V)
• External Power Supply (e.g., 9V battery or 12V adapter)
• Jumper wires
• Breadboard or motor mount base

Circuit Diagram Description

• IN1 and IN2 connected to ESP32 GPIO pins to control motor direction
• ENA connected to ESP32 PWM pin to control speed
• Motor connected to OUT1 and OUT2 on L298N
• External power supply connected to L298N power terminals

ESP32 GPIO26 —> IN1 (L298N)
ESP32 GPIO25 —> IN2 (L298N)
ESP32 GPIO14 —> ENA (L298N, PWM control)
OUT1 & OUT2 —> DC Motor
L298N GND —> ESP32 GND
L298N 12V —> External Power Source

Software Functionality

• Send HIGH/LOW signals to IN1 and IN2 for direction
• Generate PWM signal on ENA pin to control speed
• Allow for stop, forward, and reverse control

Web Interface Features (Optional Extension)

• Buttons to move motor forward, reverse, stop
• Slider to adjust speed in real time
• Dashboard-style controls for visual feedback

Implementation Steps

1. Connect the motor driver and motor to ESP32 as per circuit diagram
2. Flash MicroPython firmware to ESP32
3. Upload “** to ESP32**
4. Test motor directions and adjust speed
5. (Optional) Add a web interface for remote control

Extensions and Challenges

• Use an IR sensor or push button to trigger motor
• Control two motors for differential drive robot
• Automate direction changes based on distance sensor
• Visualize speed with a simple bar graph using OLED or web dashboard

Troubleshooting Guide

• Motor not spinning: Check power connections and motor terminals
• Motor only moves in one direction: Check IN1 and IN2 logic levels
• PWM has no effect: Confirm PWM pin assignment and duty cycle
• ESP32 resets: Ensure shared GND and proper power supply to motor

Project Code

from machine import Pin, PWM
from time import sleep

# Define pins
in1 = Pin(26, Pin.OUT)
in2 = Pin(25, Pin.OUT)
pwm = PWM(Pin(14), freq=1000)
pwm.duty(0)  # Start with 0% speed

# Move forward
def forward(speed=512):
in1.on()
in2.off()
pwm.duty(speed)

# Move reverse
def reverse(speed=512):
in1.off()
in2.on()
pwm.duty(speed)

# Stop motor
def stop():
in1.off()
in2.off()
pwm.duty(0)

# Main loop
while True:
print("Forward")
forward(800)  # speed range: 0–1023
sleep(2)

print("Reverse")
reverse(800)
sleep(2)

print("Stop")
stop()
sleep(1)

STEM Benefits

• Science: Explore the concept of electrical energy transforming into mechanical motion.
• Technology: Understand how motor drivers serve as interfaces between microcontrollers and motors.
• Engineering: Design and control electromechanical systems.
• Math: Calculate duty cycles and understand the relationship between voltage, speed, and timing.