Robots · Simulation · legged robots

Unitree Go2 ROS 2 pybullet simulation

Unitree Go2 ROS 2 pybullet simulation, adapted from inria-paris-robotics-lab/unitree_simulation. It reads pose, twist, motor_state and read_lowstate; runs publish_lowcmd, reset_simulation and unlock_base. publish_lowcmd: publish one unitree_go/LowCmd on /lowcmd; the node applies it on its next timer tick. Transmission only: no execution, arrival or stop acknowledgement. A simulator: the market serves it with a stand-in that needs no simulator install.

simulatedRisk R2licence not assertedcontract_checkedserved on the fake backend
openai4s lab add robots/inria-paris-robotics-lab__unitree_simulation

Install

Three ways to run this device. Each one serves its fake backend: no instrument, no simulator install and no upstream checkout.

OpenAI4S (one command)

shell
openai4s lab add robots/inria-paris-robotics-lab__unitree_simulation

Installs the device into the OpenAI4S Lab on its fake backend and starts it. First time? See setup below.

Or, in the workbench, open the Lab tab → Market → Install.

Standalone MHS endpoint

shell
git clone --depth 1 https://github.com/PKU-YuanGroup/OpenMHS.git && cd OpenMHS
PYTHONPATH=MHS/sdk/src python3 -m mhs serve robots/inria-paris-robotics-lab__unitree_simulation --port 7400
# in a second terminal, from the same directory:
PYTHONPATH=MHS/sdk/src python3 -m mhs describe --endpoint http://127.0.0.1:7400

Serves the device as an MHS endpoint on port 7400 from an OpenMHS clone (Python 3.10 or later, standard library only); describe prints what it offers.

Any MCP host (Claude Desktop, Cursor, …)

mcp configuration
{
  "mcpServers": {
    "unitree-simulation": {
      "command": "python3",
      "args": [
        "-m",
        "mhs",
        "serve",
        "robots/inria-paris-robotics-lab__unitree_simulation",
        "--mcp"
      ],
      "env": {
        "PYTHONPATH": "/path/to/OpenMHS/MHS/sdk/src"
      }
    }
  }
}

Add this server to the host's MCP configuration and replace /path/to/OpenMHS with the path of your OpenMHS clone. The host starts the server and talks to it on stdin and stdout.

What it does

Measures

  • pose
  • twist
  • motor_state
  • read_lowstate

Adjusts

Nothing declared.

Actions

publish_lowcmd
Publish one unitree_go/LowCmd on /lowcmd; the node applies it on its next timer tick. Transmission only: no execution, arrival or stop acknowledgement.
reset_simulation
Publish Empty on /reset; the node calls simulator.reset() and may unlock the base. A reset is not a stop: last_cmd_msg is kept and the timer keeps stepping.
unlock_base
Publish Empty on /unlock_base; the callback releases the fixed base constraint. Not a stop and has no acknowledgement.

Names as the driver declares them. Units, limits and the safety declaration are in the package's REFERENCE.md.

First-time setup

The OpenAI4S workbench with the OpenMHS lab, from a source checkout:

shell
# OpenAI4S workbench with the OpenMHS lab (source checkout)
git clone --recursive https://github.com/PKU-YuanGroup/OpenAI4S.git
cd OpenAI4S && ./setup.sh && source .venv/bin/activate
openai4s lab add robots/inria-paris-robotics-lab__unitree_simulation
openai4s serve        # open the Lab tab

The standalone endpoint and the MCP server need only an OpenMHS clone and Python 3.10 or later. More in the market's getting-started guide and on the OpenAI4S host page.

Source and evidence

Pinned commit
b53b31bc0757
Licence
NOASSERTION
Stars
8
Evidence
contract_checked on the fake backend
Backends
fake

The upstream repository asserts no licence (NOASSERTION); check it before you redistribute the upstream code.

The driver package MHS/drivers/robots/inria-paris-robotics-lab__unitree_simulation wraps the upstream code at the pinned commit. Its REFERENCE.md documents the full contract: every value, action, unit, limit and the safety declaration.