ARX X5
A 6-DoF force-controlled arm with quasi-direct-drive motors and torque sensing at every joint.
Key facts
ARX X5 is a 6-DoF force-controlled arm released in October 2023. It weighs about 3.3 kg with its gripper, carries 2 kg rated (3 kg peak), reaches 620 mm and runs a 500 Hz joint control loop through Stanford's open-source arx5-sdk.
- Degrees of freedom
- 6
- Weight
- about 3.3 kg with gripper
- Payload
- 2 kg rated, 3 kg peak
- Working radius
- 620 mm
- Control loop
- 500 Hz (arx5-sdk)
- Released
- October 2023
Specifications
Published by ARX or in the SDK documentation. Figures not published are left out; ask for the full spec sheet.
| Degrees of freedom | 6 |
|---|---|
| Weight | about 3.3 kg including gripper |
| Rated payload | 2 kg |
| Peak payload | 3 kg |
| Working radius | 620 mm |
| Reach below mount | 500 mm |
| Structure | Thin-wall aluminium alloy |
| Encoders | Dual encoders; position kept after power loss |
| Control | Joint position and torque, gravity compensation |
| Control loop | 500 Hz joint controller (arx5-sdk), about 0.4 ms motor communication delay |
| Bus | CAN, via USB-CAN or EtherCAT-CAN adapter |
| Gripper | X5 (2023): single-rail two-finger. X5 (2025): dual-rail two-finger |
| Software | ARX X5 Python SDK; arx5-sdk (Python and C++, pip install arx5-interface); ROS and MoveIt |
What it's used for
- Leader–follower teleoperation
- Arms for bimanual and mobile research rigs
- Teach and replay, keyboard or SpaceMouse control
Published work on ARX hardware
Projects whose paper, page or code names ARX hardware of this kind. All research
Questions about X5
What is the difference between X5 (2023) and X5 (2025)?
The gripper. The 2023 arm has a single-rail two-finger gripper; the 2025 arm, used on AC one, has a dual-rail two-finger gripper. The SDK settings for the gripper range differ between the two.
Can I use the X5 without ROS?
Yes. Stanford's arx5-sdk drives the arm from Python or C++ without ROS (pip install arx5-interface). ARX also publishes its own X5 Python SDK.
Can one computer run two X5 arms?
Yes. arx5-sdk includes a bimanual example for two X5 arms on can0 and can1, and its C++ layer controls several arms in one process.
Is "ARX5" the same arm?
ARX5 is the name the X5 was launched under and the name used in Stanford's SDK and in many papers.
Sources
Last updated October 10, 2026 · facts from the sources listed on this page
Further reading
Choosing a robot arm for VLA research in 2026: X5, PiPER, WidowX AI and SO-101 compared
Published specs and list prices for four popular research arms, ARX X5, AgileX PiPER, Trossen WidowX AI and SO-101, and how to choose for imitation le…
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Why force control matters for imitation learning
What force-controlled and quasi-direct-drive arms change for teleoperation, data collection and policy deployment, and which control features to check…
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Price an X5 setup.
Price, lead time and shipping options for your country.