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Enactic OpenArm 2.0

New Open Source Robot Arms
A fully open-source 7-DOF humanoid arm from Enactic of Tokyo, built for physical AI research and contact-rich manipulation. It uses backdrivable quasi-direct-drive actuators, reaches about 633 mm, weighs 5.5 kg and holds 4.1 kg nominal. The CAD is under CERN-OHL-S-2.0 and the software under Apache-2.0, so you can build one yourself, or buy a complete bimanual system from about $6,500 from certified manufacturers.
Manufacturer page — openarm.dev →
Enactic OpenArm 2.0 bimanual robot arm system with two black seven-joint arms with silver pinch grippers hanging from a shoulder unit on a black aluminium column and steel base plate — Robot Arms
Image: Enactic (OpenArm 2.0, bimanual system on its stand), background removed
View on Manufacturer Site

Specs

Price
From $6,500Bimanual system, certified manufacturers
Degrees of Freedom
7 per arm14 in the bimanual setup
Reach
633 mm606 mm per CNX Software
Weight
5.5 kgPer arm
Payload
4.1 kgNominal; 6.0 kg peak
Actuators
QDDQuasi-direct-drive, backdrivable
Control
CAN-FD1 kHz loop; CAN 2.0 fallback
End Effector
Pinch gripperRedesigned in 2.0; in-hand camera
Scale
HumanFor a person of ~160–165 cm
Construction
Al + steelCNC parts, 3D-printed casings
Hardware Licence
CERN-OHL-S-2.0CAD, STEP, Fusion 360
Software Licence
Apache-2.0Software repositories

Reference Price

Enactic designs the arm but does not manufacture it, so the price depends on the seller. Enactic's own figure is a complete bimanual OpenArm 2.0 system from about $6,500 through certified manufacturers in Japan, China and Taiwan. WowRobo lists the earlier OpenArm V1.1, one set of two arms with grippers, at $5,000 by bank transfer, $5,400 by card or CNY 38,800 in China, with a quoted 10-15 day production lead time. OpenELAB lists a WowRobo OpenArm at $9,999 each, $19,998 for a leader and follower pair. A third party reports a self-build from the published bill of materials at under $3,000. Two related open-source products complete the 2.0 ecosystem: the OpenArm Cell, a standard evaluation enclosure with fixed background, lighting, cameras and arm position, at $6,200, and the OpenArm KER, a 1.7 kg motorless shoulder-worn leader arm at 70% scale with 15-bit magnetic encoders, at $2,599. Prices exclude shipping. The spread is wide enough to confirm with the seller before ordering. robotindex does not sell this product and takes no commission from any seller listed.

Insights

Most research arms are open in the sense that you can write code for them. OpenArm is open in the sense that you can build one: CAD, STEP files, Fusion 360 assemblies, firmware, control software and simulation assets are all published, and the hardware carries CERN-OHL-S-2.0 rather than a licence covering only the software layer. That is why this page carries the Open Source badge. The more unusual part of 2.0 is the OpenArm Cell, a standard enclosure meant to let a result from one lab be reproduced in another under identical conditions; whether it is adopted widely remains to be seen. The KER leader arm maps its joints one to one to the follower, so teleoperation needs no coordinate transform. Support is broad: Hugging Face's LeRobot v0.5.0 added native OpenArm support on 9 March 2026, and Enactic maintains ROS 2, MuJoCo and URDF repositories, with the main repository at roughly 3,600 GitHub stars. Timeline: a first public beta in February 2025, the formal launch of OpenArm 01 on 23 July 2025, Release No.2 (v1.1) on 31 October 2025, OpenArm 2.0 in May 2026 with a redesigned gripper, the Cell and VR teleoperation, and KER v0.2.0 on 26 June 2026. Documentation is at docs.openarm.dev.
Verified against Enactic's documentation (docs.openarm.dev) and the enactic/openarm GitHub repository, CNX Software's 30 September 2026 write-up, the Hugging Face LeRobot OpenArm page, and WowRobo and OpenELAB seller listings, as of 4 October 2026. Flagged as uncertain: reach is 633 mm in Enactic's documentation and at MyBotShop but 606 mm in CNX Software, which cites the 2.0 CAD, and the difference may be a 1.1 versus 2.0 change; price varies by nearly four times across sellers for nominally the same system, from $5,000 at WowRobo (V1.1) to $19,998 at OpenELAB for a pair, against Enactic's own $6,500; CNX Software says most software repositories, not all, are Apache-2.0, and quotes 20-40 day lead times for 2.0 against WowRobo's 10-15 days for V1.1; and the photo is Enactic's promotional render with its studio floor and shadow removed.