Draco4 Multi-Motor EtherCAT Control Framework
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A high-performance C++ framework for controlling multiple servo motors via EtherCAT communication using the SOEM (Simple Open EtherCAT Master) library. Supports single and multi-network architectures for complex robotic systems.
Overview
The framework is built around a multi-layered architecture:
- NetworkController: Manages EtherCAT communication for a single network
- MotorController: Controls individual motors within a network
- MotorManager: Automatic motor type detection and configuration
- RobotController: Coordinates multiple networks for complex robotic systems
Features
- Multi-Motor Support: Control multiple motors on single or multiple EtherCAT networks
- CIA402 State Machine: Complete implementation for all motor types
- Multiple Control Modes: Velocity, position, and torque control with gear ratio support
- Safety Features: Torque ramping, position rate limiting, fault recovery, and emergency stop
- Automatic Detection: MotorManager automatically detects and configures motor types
- Professional Documentation: Comprehensive Doxygen-style API documentation
- Configuration Management: CSV-based motor configuration with SDO parameter upload
Supported Motors
- JD8 Series: Fully supported with position, velocity, and torque control
- JD10/JD12 Series: Compatible (same PDO structure as JD8)
- Future Motors: Extensible architecture for new motor types
Requirements
- CMake 3.16 or higher
- C++17 compatible compiler (GCC, Clang)
- SOEM library (Simple Open EtherCAT Master)
- Root privileges for EtherCAT network access
Installation
Installing SOEM
Ubuntu/Debian:
sudo apt update
sudo apt install libsoem-dev
From source:
git clone https://github.com/OpenEtherCATsociety/SOEM.git
cd SOEM
mkdir build && cd build
cmake ..
make
sudo make install
Building the Framework
mkdir build
cd build
cmake ..
make
Configuration
Motor Configuration Files
Load motor parameters from CSV files:
motor.loadConfig("config/JDLINK8_config_file.csv");
motor.uploadConfig(); // Upload to motor via SDO
Safety
Safety Features
- Torque Ramping: Smooth torque transitions to prevent mechanical stress
- Position Rate Limiting: Prevents excessive position changes per cycle
- Fault Recovery: Automatic torque ramp-down on fault detection
- Emergency Stop: Immediate motion halt via
eStop() method
- Safety Limits: Configurable torque and velocity limits
- Gear Ratio Support: Automatic scaling between motor and output shaft
Safety Requirements
- Root Privileges: EtherCAT communication requires root privileges
- Network Interface: Ensure specified interfaces are connected to EtherCAT networks
- Real-time Timing: Maintain configured update frequency for optimal performance
- Motor Safety: Always test with low torque/velocity limits initially
- Emergency Stop: Implement proper emergency stop procedures in your application
Documentation