go2_isaac_ros2

This package allows low-level (or joint-level), ROS2 control of a Unitree Go2 quadruped robot being simulated in Isaac Sim. This package is built on top of IsaacLab. This package is meant to emulate the low-level control mode of the Go2. Here, the robot is controlled by specifying joint position targets and gains to the topic /lowcmd. In low-level control mode, sports mode is disabled, so only low-level readings (like joint angles, joint velocities, IMU, and the raw lidar cloud) are available on the /lowstate and /utlidar/cloud topics.

Tested With	Version
Ubuntu	22.04
ROS2	Humble
Isaac Sim	4.5.0

TODO:

	Feature
✅	Joint position targets
⬜	Joint velocity targets
✅	Joint-level specification of Kp and Kd (proportional and derivative gain)
❌	Joint torque control
✅	Joint state and IMU
✅	Head LiDAR
⬜	Front camera
⬜	Terrain selection

Installation

First, ensure ROS2 Humble is installed.

It is recommended to install Isaac Lab within a conda / miniconda environment. Create an environment:

conda create -n go2_isaac_ros2 python=3.10
conda activate go2_isaac_ros2

Then install IsaacLab per the their instructions.

Next, create a ROS2 workspace and clone this repository into the src directory:

mkdir -p ~/go2_isaac_ros2_ws/src
cd ~/go2_isaac_ros2_ws/src
git clone https://github.com/CLeARoboticsLab/go2_isaac_ros2.git

You will also need to clone the Unitree ROS2 SDK into the src directory:

cd ~/go2_isaac_ros2_ws/src
git clone https://github.com/unitreerobotics/unitree_ros2.git

Then build the workspace:

cd ~/go2_isaac_ros2_ws
source /opt/ros/humble/setup.bash
colcon build

⚠️ You may have to build the workspace multiple times to resolve all dependencies.

⚠️ This PR is required to use the IMU sensor in Isaac Sim. Ensure this PR has been merged into your clone of Isaac Lab.

Usage

First, start the simulator:

source ~/go2_isaac_ros2_ws/install/setup.bash
conda activate go2_isaac_ros2
ros2 launch go2_isaac_ros2 launch_sim.py

Controlling the robot within Isaac Sim is the same as with hardware. To control the robot, publish unitree_go.msg.LowCmd messages to the /lowcmd topic.

Similarly, to receive observations from the robot, subscribe to the /lowstate and /utlidar/cloud topics.

Note: /clock is also published by this package to allow for time synchronization with the simulator. To synchronize ROS2 with the simulator, be sure to set the use_sim_time: true parameter when launching all nodes.

Acknowledgements

This package was inspired by the go2_omniverse package by @abizovnuralem.