USB Joystick RC Car

A DIY RC car project that uses a USB joystick to control a four-wheeled vehicle via ESP32 microcontrollers and ESP-NOW wireless communication.

🚗 Features

• USB joystick support for intuitive control
• Wireless communication using ESP-NOW protocol
• Dual control modes:
  • Simple mode (4-direction control)
  • Throttle and steering mode (proportional control)
• Real-time control with minimal latency
• Automatic safety stop on signal loss
• Support for various USB joysticks
• Configurable motor calibration
• Built-in deadband compensation

📋 Prerequisites

Hardware Requirements

Transmitter Unit

• ESP32 Development Board
• USB Joystick
• USB cables
• Power supply (USB or battery)

Receiver Unit

• ESP32 Development Board
• L298N Motor Driver
• 4× DC Motors (6-12V)
• Battery Pack (6-12V)
• Chassis (DIY or pre-made)
• Jumper Wires
• Power supply for ESP32

Software Requirements

• Arduino IDE
• Required Libraries:
  • ESP32-USB-Soft-Host
  • ESP-NOW
  • WiFi.h

🛠️ Hardware Assembly

Transmitter Setup

1. Connect the ESP32 to the USB joystick:
   • GPIO 16 → USB D+ (Green wire)
   • GPIO 17 → USB D- (White wire)
   • GND → USB GND (Black wire)
   • 5V → USB VCC (Red wire)

Receiver Setup

1. Connect ESP32 to L298N Motor Driver:

   ESP32      →    L298N
   GPIO 16    →    IN1
   GPIO 17    →    IN2
   GPIO 18    →    IN3
   GPIO 19    →    IN4
   GPIO 22    →    ENA
   GPIO 23    →    ENB
   

2. Connect L298N to Motors:

   L298N      →    Motors
   OUT1, OUT2 →    Right Motors
   OUT3, OUT4 →    Left Motors
   

3. Power Connections:

   Battery (6-12V) →    L298N 12V
   L298N 5V       →    ESP32 VIN
   GND            →    Common Ground
   

💻 Software Installation

1. Install Required Libraries:

   # Clone ESP32-USB-Soft-Host library
   git clone https://github.com/tobozo/ESP32-USB-Soft-Host.git
   # Move to Arduino libraries folder

2. Configure Arduino IDE:

   • Select ESP32 board
   • Set upload speed to 115200
   • Select correct COM port

3. Upload Code:

   • Upload transmitter code to the controller ESP32
   • Upload receiver code to the car's ESP32

⚙️ Configuration

MAC Address Setup

1. Get receiver's MAC address:

   • Upload and run the included MAC address finder sketch
   • Copy the printed MAC address

2. Update transmitter code:

   uint8_t receiverMacAddress[] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};  // Replace with your MAC

Motor Calibration

Adjust motor calibration values in MotorCalibration class:

static constexpr float leftMotorMultiplier = 1.0;   // Adjust if needed
static constexpr float rightMotorMultiplier = 1.0;  // Adjust if needed
static constexpr float turnSpeedMultiplier = 0.7;   // Adjust turn speed
static constexpr float turnRatio = 0.5;             // Adjust turn sharpness

🎮 Usage

1. Power up both transmitter and receiver units
2. Wait for ESP-NOW connection (LED indicator)
3. Control modes:
   • Default: Simple 4-direction control
   • Press joystick button to toggle throttle/steering mode
4. Emergency stop: Release joystick or power off transmitter

🔧 Troubleshooting

Common issues and solutions:

1. Motors don't respond:

   • Check power connections
   • Verify MAC address configuration
   • Check motor driver connections

2. Erratic movement:

   • Calibrate motors using multiplier values
   • Check for loose connections
   • Verify power supply stability

3. Connection issues:

   • Ensure both units are powered
   • Check MAC address configuration
   • Verify ESP-NOW initialization

📝 Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

🙏 Acknowledgments

• ESP32-USB-Soft-Host library
• ESP-NOW documentation and examples
• Arduino community for various inspirations

📞 Support

For support and questions:

• Open an issue
• Check existing documentation
• Review closed issues for similar problems

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Made with ❤️ by Ahammad Nafiz