Hexapod Robot - ESP32 + Webots

A hexapod robot project for ESP32 hardware with Webots simulation support. Uses a shared C++ codebase for locomotion logic with platform-specific servo implementations.

Project Structure

jareds-hexapod/
├── lib/
│   ├── HexapodCore/          # Platform-independent locomotion library
│   └── ESP32Servos/          # ESP32 servo implementation
├── src/                      # ESP32 firmware
├── webots/                   # Webots simulation
│   ├── worlds/               # World files
│   ├── controllers/          # Controller code
│   └── protos/               # Custom robot models
├── platformio.ini            # PlatformIO configuration
└── README.md

Hardware Requirements

ESP32 Build

• ESP32 development board
• 18× servo motors (SG90 or similar)
• 5-6V power supply for servos
• Connection wires

Servo Pin Configuration

The servos are mapped as follows (see src/main.cpp):

Leg	Position	Joints (Coxa/Femur/Tibia)
0	Front-Right	13, 12, 14
1	Middle-Right	27, 26, 25
2	Rear-Right	33, 32, 35
3	Rear-Left	34, 39, 36
4	Middle-Left	4, 16, 17
5	Front-Left	5, 18, 19

Software Requirements

For ESP32 Development

• PlatformIO (VS Code extension or CLI)
• USB drivers for ESP32

For Webots Simulation

• Webots R2023b or later
• C++ compiler (MinGW on Windows, GCC on Linux, Clang on macOS)

Building and Running

ESP32 Firmware

1. Build the project:

   cd c:\jaredcode\jareds-hexapod
   pio run

2. Upload to ESP32:

   pio run --target upload

3. Monitor serial output:

   pio device monitor

Webots Simulation

1. Open Webots

2. Load the world file:

   • File → Open World
   • Navigate to: c:\jaredcode\jareds-hexapod\webots\worlds\hexapod.wbt

3. Build the controller (first time only):

   • The controller should auto-compile when you load the world
   • Alternatively, in the controller directory:

     cd webots/controllers/hexapod_controller
     make

4. Run the simulation:

   • Click the Play button in Webots
   • The hexapod should initialize and move to standing position

Code Architecture

Shared Library (lib/HexapodCore)

Platform-independent hexapod control logic:

• Hexapod.h/cpp: Main hexapod control class
• ServoInterface.h: Abstract servo interface
• Kinematics.h/cpp: Leg kinematics (future)
• Gait.h/cpp: Gait patterns (future)

Platform-Specific Implementations

ESP32 (lib/ESP32Servos):

• Uses ESP32Servo library
• Implements ServoInterface for physical servos

Webots (webots/controllers/hexapod_controller):

• Uses Webots Motor and PositionSensor devices
• Implements ServoInterface for simulated servos
• Shares same Hexapod class as ESP32

Current Features

• ✅ 18-servo hexapod control (6 legs × 3 joints)
• ✅ Hardware abstraction layer
• ✅ ESP32 firmware with servo control
• ✅ Webots simulation environment
• ✅ Basic poses (stand, rest)

Planned Features

• Inverse kinematics for leg positioning
• Tripod gait for walking
• Wave gait for slow walking
• Turning and rotation
• Remote control (Bluetooth/WiFi)
• IMU integration for balance
• Autonomous navigation

Development Workflow

1. Design gaits in Webots: Quickly iterate on locomotion algorithms
2. Test in simulation: Verify behavior without hardware
3. Deploy to ESP32: Same code runs on real hardware
4. Fine-tune: Adjust parameters for physical characteristics

Troubleshooting

ESP32 Build Errors

• Ensure PlatformIO is installed correctly
• Check that ESP32 board is selected in platformio.ini
• Verify USB connection and drivers

Webots Controller Not Starting

• Check that WEBOTS_HOME environment variable is set
• Verify Makefile paths match your installation
• Rebuild controller: cd webots/controllers/hexapod_controller && make clean && make

Servos Not Moving

• Check power supply (servos need 5-6V, ESP32 GPIO is 3.3V)
• Verify pin connections match SERVO_PINS array
• Test individual servos with simple sketch

License

MIT License - see LICENSE file for details.

Contributing

Contributions welcome! Please open an issue or pull request.