#
OpenArm

OpenArm is an open-source 7DOF humanoid arm designed for physical AI research and deployment.

To get your OpenArm, assembled or DIY, and join the global community, browse verified and certified manufacturers worldwide at openarm.dev.

##
What’s Unique?

- Human-Scale Design: OpenArm is designed with human-like proportions, scaled for a person around 160-165cm tall. This provides an optimal balance between practical reach and manageable inertia for safe, responsive operation.

- Safety-First Architecture: Built with QDD backdrivable motors and high compliance, OpenArm prioritizes safe human-robot interaction while maintaining practical payload capabilities (6.0kg peak / 4.1kg nominal) for real-world tasks.

- Built for Durability: Critical structural components use aluminum and stainless steel construction, ensuring robust performance for repetitive data collection and continuous research use.

- Fully Accessible & Buildable: Every component, from CNC parts and 3D-printed casings to electrical wiring is designed to be purchasable and buildable by individual researchers and labs, with complete fabrication data provided.

- Practical & Affordable: At $6,500 USD for a complete bimanual system, OpenArm delivers research-grade capabilities at a fraction of traditional humanoid robot costs.

##
Platform Requirements

> **Linux Only**: OpenArm currently only works on Linux. The CAN bus USB adapter does not have macOS drivers and has not been tested on Windows.

##
Safety Guide

Before operating OpenArm, please read the official safety guide. Key points:

- Secure installation: Fasten the arm to a flat, stable surface with screws or clamps
- Safe distance: Keep body parts and objects outside the range of motion during operation
- Protective equipment: Always wear safety goggles; use additional PPE as needed
- Payload limits: Do not exceed specified payload limits (6.0kg peak / 4.1kg nominal per arm)
- Emergency stop: Know the location and operation of the emergency stop device
- Regular inspection: Check for loose screws, damaged mechanical limits, unusual noises, and wiring damage

##
Hardware Setup

Follow the official OpenArm hardware documentation for:

- Bill of materials and sourcing
- 3D printing instructions
- Mechanical assembly
- Electrical wiring

The hardware repositories are available at github.com/enactic/openarm.

##
CAN Bus Setup

OpenArm uses CAN bus communication with Damiao motors. Once you have the CAN bus USB adapter plugged into your Linux PC, follow the Damiao Motors and CAN Bus guide to configure the interface.

Quick setup:

    # Setup CAN interfaces
    lerobot-setup-can --mode=setup --interfaces=can0,can1

    # Test motor communication
    lerobot-setup-can --mode=test --interfaces=can0,can1

##
Install LeRobot 🤗

Follow our Installation Guide, then install the Damiao motor support:

    pip install -e ".[damiao]"

##
Usage

###
Follower Arm (Robot)

Command
API example

    lerobot-calibrate \
        --robot.type=openarm_follower \
        --robot.port=can0 \
        --robot.side=right \
        --robot.id=my_openarm_follower

###
Leader Arm (Teleoperator)

The leader arm is used for teleoperation - manually moving it to control the follower arm.

Command
API example

    lerobot-calibrate \
        --teleop.type=openarm_leader \
        --teleop.port=can1 \
        --teleop.id=my_openarm_leader

###
Teleoperation

To teleoperate OpenArm with leader-follower control:

    lerobot-teleoperate \
        --robot.type=openarm_follower \
        --robot.port=can0 \
        --robot.side=right \
        --robot.id=my_follower \
        --teleop.type=openarm_leader \
        --teleop.port=can1 \
        --teleop.id=my_leader

###
Bimanual Teleoperation

To teleoperate a bimanual OpenArm setup with two leader and two follower arms:

    lerobot-teleoperate \
        --robot.type=bi_openarm_follower \
        --robot.left_arm_config.port=can0 \
        --robot.left_arm_config.side=left \
        --robot.right_arm_config.port=can1 \
        --robot.right_arm_config.side=right \
        --robot.id=my_bimanual_follower \
        --teleop.type=bi_openarm_leader \
        --teleop.left_arm_config.port=can2 \
        --teleop.right_arm_config.port=can3 \
        --teleop.id=my_bimanual_leader

###
Recording Data

To record a dataset during teleoperation:

    lerobot-record \
        --robot.type=openarm_follower \
        --robot.port=can0 \
        --robot.side=right \
        --robot.id=my_follower \
        --teleop.type=openarm_leader \
        --teleop.port=can1 \
        --teleop.id=my_leader \
        --repo-id=my_hf_username/my_openarm_dataset \
        --fps=30 \
        --num-episodes=10

##
Configuration Options

###
Follower Configuration

Parameter | Default | Description
--- | --- | ---
`port` | - | CAN interface (e.g., `can0`)
`side` | `None` | Arm side: `"left"`, `"right"`, or `None` for custom limits
`use_can_fd` | `True` | Enable CAN FD for higher data rates
`can_bitrate` | `1000000` | Nominal bitrate (1 Mbps)
`can_data_bitrate` | `5000000` | CAN FD data bitrate (5 Mbps)
`max_relative_target` | `None` | Safety limit for relative target positions
`position_kp` | Per-joint | Position control proportional gains
`position_kd` | Per-joint | Position control derivative gains

###
Leader Configuration

Parameter | Default | Description
--- | --- | ---
`port` | - | CAN interface (e.g., `can1`)
`manual_control` | `True` | Disable torque for manual movement
`use_can_fd` | `True` | Enable CAN FD for higher data rates
`can_bitrate` | `1000000` | Nominal bitrate (1 Mbps)
`can_data_bitrate` | `5000000` | CAN FD data bitrate (5 Mbps)

##
Motor Configuration

OpenArm uses Damiao motors with the following default configuration:

Joint | Motor Type | Send ID | Recv ID
--- | --- | --- | ---
joint_1 (Shoulder pan) | DM8009 | 0x01 | 0x11
joint_2 (Shoulder lift) | DM8009 | 0x02 | 0x12
joint_3 (Shoulder rotation) | DM4340 | 0x03 | 0x13
joint_4 (Elbow flex) | DM4340 | 0x04 | 0x14
joint_5 (Wrist roll) | DM4310 | 0x05 | 0x15
joint_6 (Wrist pitch) | DM4310 | 0x06 | 0x16
joint_7 (Wrist rotation) | DM4310 | 0x07 | 0x17
gripper | DM4310 | 0x08 | 0x18

##
Troubleshooting

###
No Response from Motors

1. Check power supply connections
2. Verify CAN wiring (CAN-H, CAN-L, GND)
3. Run diagnostics: `lerobot-setup-can --mode=test --interfaces=can0`
4. See the Damiao troubleshooting guide for more details

###
CAN Interface Not Found

Ensure the CAN interface is configured:

    ip link show can0

##
Resources

- OpenArm Website
- OpenArm Documentation
- OpenArm GitHub
- Safety Guide
- Damiao Motors and CAN Bus

Update on GitHub