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

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)

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

from lerobot.robots.openarm_follower import OpenArmFollower, OpenArmFollowerConfig

config = OpenArmFollowerConfig(
    port="can0",
    side="right",  # or "left" for left arm
    id="my_openarm_follower",
)

follower = OpenArmFollower(config)
follower.connect()

# Read current state
obs = follower.get_observation()
print(obs)

# Send action (position in degrees)
action = {
    "joint_1.pos": 0.0,
    "joint_2.pos": 0.0,
    "joint_3.pos": 0.0,
    "joint_4.pos": 45.0,
    "joint_5.pos": 0.0,
    "joint_6.pos": 0.0,
    "joint_7.pos": 0.0,
    "gripper.pos": 0.0,
}
follower.send_action(action)

follower.disconnect()

Leader Arm (Teleoperator)

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

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

from lerobot.teleoperators.openarm_leader import OpenArmLeader, OpenArmLeaderConfig

config = OpenArmLeaderConfig(
    port="can1",
    id="my_openarm_leader",
    manual_control=True,  # Disable torque for manual movement
)

leader = OpenArmLeader(config)
leader.connect()

# Read current position (as action to send to follower)
action = leader.get_action()
print(action)

leader.disconnect()

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

Leader Configuration

Motor Configuration

OpenArm uses Damiao motors with the following default configuration:

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