OpenArm
One-line judgment
OpenArm is the strongest first-tier main experiment platform candidate for bouquet-making VLA work. Official LeRobot support, bimanual configuration, 7-DoF reach, and a low BOM line up well, but final performance depends on the end-effector and sensing stack.
Overview
OpenArm is an open-source 7-DoF humanoid robot arm led by Enactic in Japan. It is listed in the official Hugging Face LeRobot robot documentation and exposes single-arm and bimanual leader-follower workflows through openarm_follower, openarm_leader, bi_openarm_follower, and bi_openarm_leader.
| Item | Details |
|---|---|
| Lead | Enactic |
| Type | 7-DoF humanoid robot arm |
| LeRobot support | Official docs for single-arm/bimanual teleoperation and dataset recording |
| Actuation | Damiao QDD motors, CAN/CAN-FD |
| Payload | 4.1kg nominal, 6.0kg peak per arm before end-effector weight |
| Price | About $6,500 BOM for a complete bimanual system |
| Openness | CAD, URDF/xacro, CAN control, ROS 2, teleoperation repos |
| Main use | Contact-rich manipulation, bimanual data collection, imitation learning, VLA policy experiments |
Fit for Flower Handling and Bouquet Making
OpenArm is one of the most interesting purchase candidates among officially supported LeRobot platforms. It has much more reach and payload than SO-101, is much cheaper than Reachy 2 or industrial dual-arm cells, and the bimanual setup is exposed directly through LeRobot commands.
| Criterion | Assessment |
|---|---|
| Bimanual work | Strong fit. bi_openarm_follower is documented for bimanual leader-follower control. |
| Reach for floral tasks | Strong fit. Human-scale arm proportions make tabletop stem alignment, wrapping, and handoff tasks practical. |
| Dexterity | The arm is capable, but delicate petals/stems will depend on the end-effector. Consider soft pads, LEAP/Allegro, or Robotiq-style grippers. |
| Durability | The project describes aluminum and stainless steel structural parts for repeated data collection. |
| Price | Around $6.5k BOM for bimanual hardware is very aggressive for research-grade dual-arm manipulation. |
| Customization | Very high. Hardware files, simulation, ROS 2, and CAN control are open. |
| Risk | Newer ecosystem than ALOHA or Franka. Confirm assembled-unit availability and lead time before purchase. |
Recommended role: first-tier experimental platform for bouquet-making VLA data collection.
Main caveat: delicate grasping quality will depend heavily on gripper choice and tactile/vision setup.
LeRobot Integration
LeRobot documents both single-arm and bimanual leader-follower setups for OpenArm. The important part is the workflow, not copying long command blocks into the hardware note.
| Flow | Meaning |
|---|---|
openarm_follower / openarm_leader | Validate the camera-action data loop with one arm |
bi_openarm_follower / bi_openarm_leader | Collect bimanual demonstrations for bouquet work |
lerobot-record | Save datasets in the Hugging Face Hub flow for ACT, SmolVLA, pi0-style, or custom VLA experiments |
Use the LeRobot OpenArm docs for exact commands, since command-line flags can change across versions.
Hardware and Software Stack
| Component | Details |
|---|---|
| DoF | 7-DoF per arm |
| Communication | CAN/CAN-FD |
| Control | Position control, gravity compensation, teleoperation, force-feedback-oriented design |
| Simulation | MuJoCo and Isaac Sim/Isaac Lab repositories |
| ROS | ROS 2 packages available |
| Hardware license | OpenArm hardware repo uses CERN-OHL-S-2.0 |
| Software license | Main software repos use Apache 2.0 |
OpenArm is not just a low-cost arm. Its value is that it is an open hardware stack shaped around VLA data collection. With a bimanual leader setup, human demonstrations for flower trimming and bouquet assembly can be collected in the same LeRobot pipeline used for ACT, SmolVLA, pi0-style policies, and future custom VLA inference.
Purchase Checklist
- Confirm assembled or DIY kit supplier and lead time.
- Prepare CAN-FD adapters, power, emergency stop, and table mounting.
- Keep any cutting tool tests inside a physical safety cell.
- Start with the default gripper, then switch to soft pads, compliant grippers, or dexterous hands if stem damage is high.
- Validate the single-arm
openarm_followerpipeline before expanding tobi_openarm_follower.
References
- Hugging Face LeRobot - OpenArm
- OpenArm Official Site
- OpenArm GitHub
- OpenArm Hardware Docs
- LeRobot Policy Deployment