Introduction

Here are the ROS simulation packages for Unitree robots, You can load robots and joint controllers in Gazebo, so you can perform low-level control (control the torque, position and angular velocity) of the robot joints. Please be aware that the Gazebo simulation cannot do high-level control, namely walking. Aside from these simulation functions, you can also control your real robots in ROS with the unitree_ros_to_real packages. For real robots, you can do high-level and low-level control using our ROS packages.

Packages

Robot descriptions

Every robot model lives under robots/. See robots/README.md for the model files, variants and launch files of each package.

Robot	Type	Package / model	DOF
A1	Quadruped	a1_description	12
A2	Quadruped	a2_description	12
AlienGo	Quadruped	aliengo_description	12
As2	Quadruped	as2_description	12
B1	Quadruped	b1_description	12
B2	Quadruped	b2_description	12
Go1	Quadruped	go1_description	12
Go2	Quadruped	go2_description	12
Laikago	Quadruped	laikago_description	12
As2-W	Wheeled quadruped	as2w_description	12 + 4
B2-W	Wheeled quadruped	b2w_description	12 + 4
Go2-W	Wheeled quadruped	go2w_description	12 + 4
G1	Humanoid	g1_description	23 / 29
G1+	Humanoid	g1_pl.urdf	31
G1 with BrainCo Hand	Humanoid	g1_with_brainco_hand	61
H1	Humanoid	h1_description	19 (45)
H1-2	Humanoid	h1_2_description	27 (51)
H2	Humanoid	h2_description	31
H2 Plus	Humanoid	h2_plus	31 (75)
H2-X	Humanoid	h2x_description	31 (37)
R1	Humanoid	r1_description	26
R1 Air	Humanoid	r1_air_description	20
G1-D	Wheeled humanoid	g1_d_description	17 / 19
H2-D	Wheeled humanoid	h2d_description	19
R1-A7-D	Wheeled mobile manipulator	r1d_description	21
AlienGo with Z1	Mobile manipulator	aliengoZ1_description	12 + 6
R1-7a	Robotic arm	r1_7a_description	7
R1-A5	Dual-arm upper body	r1_a5_description	13
R1-A7	Dual-arm upper body	r1_a7_description	17
Z1	Robotic arm	z1_description	6
Dex1-1 / Dex2/5 / Dex3-1 / Dex5-1	Dexterous hands	dexterous_hand_description	2 / 10 / 7 / 20
B2 (MuJoCo)	Quadruped	b2_description_mujoco	12

DOF counts the actuated joints in the model files: 23 / 29 denotes model variants, 19 (45) is the body DOF with dexterous hands, 31 (37) adds transmission joints, 12 + 4 adds the wheel joints, and the hand figures are actuated joints per hand. G1+ is a URDF variant (g1_pl.urdf) inside g1_description rather than a separate package.

Controllers, simulation and messages

Package	Description
unitree_controller	Stand/servo nodes and disturbance or pose publishers: unitree_servo, unitree_external_force, unitree_move_kinetic
unitree_gazebo	Gazebo launch files, worlds and plugins (foot contact force, force drawing)
unitree_legged_control	controller_manager plugin UnitreeJointController for position, velocity and torque control
unitree_ros_to_real	Submodule with unitree_legged_msgs and the real-robot ROS packages

Dependencies

• ROS Melodic or ROS Kinetic (has not been tested)
• Gazebo8
• unitree_legged_msgs: unitree_legged_msgs is a package under unitree_ros_to_real.

Build

For ROS Melodic:

sudo apt-get install ros-melodic-controller-interface  ros-melodic-gazebo-ros-control ros-melodic-joint-state-controller ros-melodic-effort-controllers ros-melodic-joint-trajectory-controller

For ROS Kinetic:

sudo apt-get install ros-kinetic-controller-manager ros-kinetic-ros-control ros-kinetic-ros-controllers ros-kinetic-joint-state-controller ros-kinetic-effort-controllers ros-kinetic-velocity-controllers ros-kinetic-position-controllers ros-kinetic-robot-controllers ros-kinetic-robot-state-publisher ros-kinetic-gazebo8-ros ros-kinetic-gazebo8-ros-control ros-kinetic-gazebo8-ros-pkgs ros-kinetic-gazebo8-ros-dev

And open the file unitree_gazebo/worlds/stairs.world. At the end of the file:

<include>
    <uri>model:///home/unitree/catkin_ws/src/unitree_ros/unitree_gazebo/worlds/building_editor_models/stairs</uri>
</include>

Please change the path of building_editor_models/stairs to the real path on your PC.

Then you can use catkin_make to build:

cd ~/catkin_ws
catkin_make

If you face a dependency problem, you can just run catkin_make again.

Detail of Packages

unitree_legged_control:

It contains the joints controllers for Gazebo simulation, which allows users to control joints with position, velocity and torque. Refer to "unitree_ros/unitree_controller/src/servo.cpp" for joint control examples in different modes.

The description of robots:

Each robot has a description package under robots/, containing meshes plus URDF and Xacro files (and MJCF where available). The robot table lists every model with its DOF; see robots/README.md for variants and launch files. Take Laikago for example, you can check the model in Rviz by:

roslaunch laikago_description laikago_rviz.launch

unitree_gazebo & unitree_controller:

You can launch the Gazebo simulation with the following command:

roslaunch unitree_gazebo normal.launch rname:=a1 wname:=stairs

Where the rname means robot name. Robots with a complete Gazebo controller setup (xacro/robot.xacro and config/robot_control.yaml) are laikago, aliengo, a1, b1, b2, go1 and go2; the remaining descriptions ship RViz or display launch files only. The wname means world name, which can be earth, space or stairs. And the default value of rname is laikago, while the default value of wname is earth. In Gazebo, the robot should be lying on the ground with joints not activated.

1. Stand controller

After launching the gazebo simulation, you can start to control the robot:

rosrun unitree_controller unitree_servo

And you can add external disturbances, like a push or a kick:

rosrun unitree_controller unitree_external_force

2. Position and pose publisher

Here we demonstrated how to control the position and pose of robot without a controller, which should be useful in SLAM or visual development.

Then run the position and pose publisher in another terminal:

rosrun unitree_controller unitree_move_kinetic

The robot will turn around the origin, which is the movement under the world coordinate frame. And inside of the source file move_publisher.cpp, we also provide the method to move using the robot coordinate frame. You can change the value of def_frame to coord::ROBOT and run the catkin_make again, then the unitree_move_publisher will move robot under its own coordinate frame.

Z1

You can launch the z1 Gazebo simulation with the following command:

roslaunch unitree_gazebo z1.launch

After launching the gazebo simulation, you can start to control the z1 robot by z1_sdk.
see z1_documentation