trossen_arm_sim

Runs trossen_arm in simulation. The server speaks the wire protocol of the WidowX AI (wxai_v0) arm controller (firmware v1.10), so the unmodified trossen_arm driver connects to it as if it were real hardware — the arm runs in MuJoCo instead.

Install

pip install .

Clients need trossen_arm==1.10.* (the driver rejects other firmware versions).

Usage

trossen-arm-sim                        # default scene: arm on a ground plane
trossen-arm-sim scene.xml              # custom scene
mjpython -m trossen_arm_sim --viewer   # MuJoCo viewer (macOS needs mjpython)

Point any trossen_arm client at 127.0.0.1 instead of the robot's IP:

driver.configure(
    trossen_arm.Model.wxai_v0,
    trossen_arm.StandardEndEffector.wxai_v0_follower,
    "127.0.0.1",
    False,
)

A custom scene is MJCF that includes the arm via the WIDOWX_XML placeholder, replaced with the installed arm model path at load time (TROSSEN_ARM_ASSET_DIR likewise for the packaged asset directory):

<mujoco>
  <include file="WIDOWX_XML"/>
  <worldbody>
    <light pos="0 0 1.5" dir="0 0 -1" directional="true"/>
    <geom name="floor" size="0 0 0.05" type="plane" rgba="0.5 0.5 0.5 1"/>
  </worldbody>
</mujoco>

Example

Numpad scene plus a client that presses its keys:

trossen-arm-sim examples/scene_numpad.xml     # terminal 1
python examples/press_button.py 1 2 3 enter   # terminal 2

Publish

Bump version in pyproject.toml, then:

pip install build twine
python -m build
twine upload dist/*

Attributions

The arm model and meshes in trossen_arm_sim/assets/ are from trossen_arm_mujoco, Copyright (c) 2025 Trossen Robotics, licensed under BSD-3-Clause.