I have one robot platform, metal and rigid.

I want to use this off-road, which is more interesting :-)

But with a rigid chassis, there is no good performance off-road.

Because of this, I made my first robot platform, 3D printed, with off-road crawler suspension.

And I made one firmware in ESP32 Arduino, with advanced features:

• Web control (no need for an app, just a browser)
• Car control by virtual joystick (It is good because you do not need to see the screen to touch the control buttons and it's very fun)
• Another virtual joystick to control the servo of the camera
• Slow speed mode, using PWM over PWM, to give slow speeds but high torque.
• And More....

Technical Implementation: WiFi and 4WD Driving

The project reveals the hidden layers of wireless off-road robotics:

• Mobility layer: Using Four High-Torque DC Motors, the robot can move across rough terrain by varying the speed of each motor pair.
• Wireless Interface layer: The ESP32 Microcontroller (in this build) acts as a web server, allowing you to control the robot from any smartphone or tablet connected to the same WiFi network.
• Communication & Control layer: The ESP32 handles both the WiFi communication and generates the PWM signals to control the motor driver directly, sending movement commands (e.g., Forward, Left, Right).
• Actuation layer: A motor driver module (like an L298N or similar) provides the high current needed to drive all four motors from the low-voltage microcontroller signals.

Hardware Infrastructure

• ESP32 Microcontroller: The integrated "brain" of the project, managing WiFi, the web server, and generating motor control signals.
• Motor Driver (e.g., L298N): Effectively handles the high-voltage power required to drive all four motor coils while protecting the microcontroller.
• High-Torque DC Motors: Providing the physical movement and orientation for each of your robot's travels.
• 3D-Printed Crawler Chassis: The custom physical frame that houses the electronics and provides independent suspension for off-road performance.
• Li-Po Battery Pack: Essential for providing the high current needed to drive all four motors simultaneously.
• Micro-USB Cable: Used to program the ESP32 directly from your computer.

Locomotion and Control Loop

The off-road robot is designed to be very efficient:

1. Initialize Hardware: Correctly seat the ESP32 module, motor driver, and motors on your custom chassis.
2. Setup Web Server: In the ESP32 code, create a web-based dashboard with a virtual joystick interface for the user.
3. Driving Execution: Use a smartphone or computer browser to send commands wirelessly to the robot via the joystick.
4. System Feedback: Watch the movement in real-time via the camera stream while the PWM-over-PWM logic provides smooth, high-torque control at low speeds.

See it in action (off-road):

Future Expansion

• OLED Dashboard Integration: Add a small OLED display to show current WiFi signal strength and remaining battery life.
• Multi-Sensor Navigation Support: Connect sensors (e.g., ultrasonic or IMU) to help the robot navigate complex terrain or mazes autonomously.
• Cloud Interface Support: Implement a cloud dashboard to control and track your robot from anywhere in the world.
• Advanced Control Systems: Add an IR receiver and remote control as a backup manual control system, or implement more advanced motor control profiles.

ESPlorer I - Arduino Off-Road Robot is a perfect project for any electronics enthusiast looking for a more interactive and engaging robotics tool!