🔧 Components Used
🎯 Lesson Objective
In this lesson, students will understand:
• The hardware components required to build the Single Limit Switch Bumper Robot
• The purpose of each component in the robot system
• How these components work together to detect obstacles and control movement
This lesson introduces the electronic and mechanical components used in the Single Limit Switch Bumper Robot project.
1️⃣ ESP32 Microcontroller
The ESP32 acts as the main controller of the robot.
It performs the following tasks:
🧠 Reads the signal from the limit switch
⚙ Processes the input signal
🚗 Sends commands to the motor driver
📡 Executes the program logic
When the robot hits an obstacle, the limit switch sends a signal to the ESP32.
The ESP32 processes this signal and controls the motors accordingly.
The ESP32 is widely used in robotics because it provides:
• Multiple input/output pins
• Fast processing capability
• Reliable performance
2️⃣ Limit Switch
The limit switch is used as the bumper sensor for the robot.
It is placed at the front of the robot, so when the robot hits an obstacle the switch gets pressed.
Behavior of the switch:
• Pressed → Signal sent to ESP32
• Released → No signal sent
The ESP32 reads this signal and triggers the robot to change direction.
Limit switches are commonly used in:
🏭 Industrial machines
🚪 Automatic doors
🤖 Collision detection systems
📦 Conveyor belt systems
3️⃣ L298N Motor Driver
The L298N motor driver controls the DC motors of the robot.
The ESP32 cannot directly power motors because motors require higher current.
The motor driver acts as an interface between:
🧠 ESP32 microcontroller
⚙ DC motors
The ESP32 sends control signals to the motor driver, and the motor driver supplies power to the motors.
Using the motor driver, the robot can perform movements such as:
➡ Move forward
⬅ Move backward
↩ Turn left
↪ Turn right
🛑 Stop
4️⃣ DC Motors
The DC motors provide movement for the robot.
In this project, two motors are used:
• One motor for the left wheel
• One motor for the right wheel
By controlling these motors independently, the robot can move forward, reverse, or turn when an obstacle is detected.
DC motors are commonly used in robotics because they are simple and easy to control.
5️⃣ Robot Chassis
The robot chassis forms the physical structure of the robot.
It holds all components such as:
• ESP32
• Motor driver
• Motors
• Battery pack
• Limit switch
The chassis also includes wheels and a caster wheel for balance.
The limit switch is mounted on the front bumper area so that it gets pressed when the robot hits an obstacle.
6️⃣ Jumper Wires
Jumper wires are used to connect electronic components together.
These wires allow electrical signals to travel between:
🔌 ESP32
🔘 Limit switch
⚙ Motor driver
Proper wiring ensures that all components communicate correctly.
Loose or incorrect wiring can cause the robot to malfunction.
7️⃣ Power Supply
The robot requires a power source to operate.
Possible power sources include:
🔋 Lithium battery pack
🔋 Rechargeable batteries
🔋 External power supply
The power supply provides energy for:
⚙ Motors
🧠 ESP32
🔘 Sensors
A stable power supply ensures reliable robot operation.
8️⃣ How the Components Work Together
All components in the Single Limit Switch Bumper Robot work together as a system.
The process works as follows:
1️⃣ The robot moves forward continuously.
2️⃣ When the robot hits an obstacle, the limit switch is pressed.
3️⃣ The limit switch sends a signal to the ESP32.
4️⃣ The ESP32 processes the signal.
5️⃣ The ESP32 sends commands to the motor driver.
6️⃣ The robot moves backward and changes direction.
This allows the robot to detect obstacles and avoid them automatically.
🚀 What Happens Next
Now that you understand the components used in the Single Limit Switch Bumper Robot, the next step is to connect these components together.