ROS Operation

ROS Simulation

1. Set ros workspace

If the user is not familiar with the path setting, please create the folder named unitree_ws/src and move folder unitree_ros folder in it, which should be ~/unitree_ws/src/unitree_ros. Then download the folder unitree_legged_msgs, move it to ~/unitree_ws/src/.

You can also use the following commands to set the ros workspace.

mkdir -p ~/unitree_ws/src
mv unitree_ros ~/unitree_ws/src/
mv unitree_legged_msgs ~/unitree_ws/src/

Then set the ros workspace like this:

cd ~/unitree_ws
catkin_make
echo "source ~/unitree_ros/devel/setup.bash">>~/.bashrc
source ~/.bashrc

Now, run roslaunch unitree_gazebo z1.launch, if successfully configured, the simulation interface of Gazebo will be displayed.

roslaunch unitree_gazebo z1.launch

Note

After entering RosLaunch Z, press tap to check whether the terminal will automatically complete. If rosLaunch is successfully programmed, that means the path setting is successful.

2. CMakeLists Configuration

Open the CMakeLists.txt in the z1_controller folder and change the compilation conditions as follows.

# set(COMMUNICATION UDP)             #UDP
set(COMMUNICATION ROS)               #ROS

3. Compile

Now, compile the project.

mkdir build
cd build
cmake ..
make

Execute the executable file ./z1_ctrl in folder build. The default control mode is SDK, if you need to use keyboard control, use ./z1_ctrl k When executing this command, the terminal will continuously print statements, such as [WARNING] UDPPort::recv, unblock version, wait time out, this is normal because we have not started the robotic arm SDK to communicate with the robotic arm controller.

Note

Various information will be printed in this window, please observe the content of this window.

4. Open folder z1_SDK and create folder build in it (open the third terminal).

mkdir build
cd build
cmake ..
make

Execute the executable file in folder build. There are two executable files generated, example_lowcmd_send and bigdemo. This time we run bigdemo.

./bigdemo_basic

Note

Keyboard Operation:The specific keys will be introduced in state machine section.

First press 2 on the keyboard and then press key 0, the robotic arm will enter the label operation state machine. Input forward at the prompt, then click enter, the robotic arm will run forward. Press ~ again, return to the origin. After returning to the origin, it will automatically enter the joint control mode. At this time, the rotation of the robotic arm can be controlled by long press according to the following keys.

Joint ID	Keyboard	Joint Action (right hand)
0	Q/A	positive/negative
1	W/S	positive/negative
2	D/E	positive/negative
3	R/F	positive/negative
4	T/G	positive/negative
5	Y/H	positive/negative
Gripper	up/down	positive/negative

Now, we have completed the simulation operation.

The whole process is: Run ROS–>Run z1_ctrl–>Run SDK instance.

Multiple robots control

1. open the directory z1_controller, set Communication in CMakeLists.txt to UDP.

2. copy the directory z1_controller, named as z1_controller_111.

3. open the directory z1_controller_111.

In main.cpp:

set UDP port (Line51) as shown in the following example:

ctrlComp->cmdPanel = new ARMSDK(events, emptyAction, "127.0.0.1", 8074, 8073, 0.002);

In config.xml:

set IP to 192.168.123.111, set Port to 8882.

In unitreeArmTools.py

set the second robotic arm IP to 192.168.123.111.

As described previously, proceed as follows:

execute z1_ctrl in z1_controller at the first terminal, which communicates with the robotic arm 110. execute z1_ctrl in z1_contrller_111 at the second terminal, which communicates with the robotic arm 111. execute lowcmd_multirobots in z1_sdk at the third terminal.

And then we can see that the Joint1 of both robotic arm has turned at an angle.