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Dex5-1 Hand

Unitree has only recently published an integration guide for the Dex5-1 on the H1-2. This page gathers what the official documentation covers, what we found out in the lab and what is still open. Items marked to be verified have not been confirmed by Unitree.

The Dex5-1 is a back-drivable five-finger hand with 20 degrees of freedom (16 active): 4 in the thumb and 3 in each of the other four fingers. It weighs about 1100 g, measures 217.3 × 127.5 × 72.1 mm and lifts up to 3.5 kg (palm facing down). It optionally has 94 tactile sensors. Power is 24 to 60 V (XT30) and communication is USB 2.0. See the full specifications in About Dex5-1 Hand.

Installation​

Mechanical. Remove the dummy hand from the H1-2 wrist and fix the Dex5-1 to the wrist flange with the four M4 holes (6 mm deep, Ø37 mm circle) shown in Unitree's mounting drawing. This installation video (thanks to the amazing unitree community on reddit!) shows the step-by-step procedure. Power the robot off before touching anything: connecting or disconnecting aviation connectors while the robot is on is forbidden (see Components and interfaces).

Electrical. The 1.8 m cable of each hand splits into two leads: a power lead (two thick wires, XT30 plug) and a communication lead (four thin wires, 4-pin JST plug, which becomes USB-A through the adapter board included in the kit). The kit also includes a breakout box (hub) and a wrist adapter with a 721_ARM_PW_V0.2 board, with no manual. Two wirings are consistent with the parts, both to be verified with a multimeter before powering on:

  • A, power through the wrist: H1-2 wrist connectors → wrist adapter → hand XT30. The hand's USB goes to the hub and from the hub to the PC4.
  • B, everything through the hub: H1-2 24 V output → hub (black XT30) → hand XT30, with USB going through the hub to the PC4. This 24 V cable was not included in the kit.

Software on the PC4. The hand does not work without the dex5_anemone server, which talks to the hands over USB and publishes the DDS topics. First install unitree_sdk2 and libusb-1.0-0, extract the package that matches the architecture (the PC4 is x86_64), then run the check and the server.

Server packages

tar xzf dex5_anemone_package_x86_64_20260509_223948.tar.gz
cd dex5_anemone_package_x86_64
./dex5_pre_check.sh
cd bin && ./dex5_anemone

Logs are written to the log folder. To test joint motion, the package includes bin/urdf_motion_test (instructions in docs/README_URDF_TEST.md).

Control​

The Dex5-1 uses the same IDL as the Dex3-1 (HandCmd_ and HandState_), at 1000 Hz. The supported mode is URDF joint control: 20 URDF indices command the 16 motors and Unitree handles the kinematics. Start with position mode (mode = 1) using kp = 0.10 and kd = 0.001 on the four fingers, and kp = 1.0 and kd = 0.02 on the thumb (index 16). Unitree's example publishes commands on rt/dex5/left/cmd and reads the state from rt/dex5/left. Details in Upper-Layer Communication Method Based on DDS.

References​

We had some trouble trying to figure out how to install the hand and the software. The lab document has the photos, a description of each part and the questions sent to Unitree.