Ros2 self study notes: rqt visualization tool

RQT and rviz similar , It's all based on qt Visual tools .RQT be relative to rviz The interface is more concise , Easy to operate
download RQT

sudo apt install ros-foxy-rqt

Input... At the terminal rqt You can open

1 RQT Print log information
choice plugins->logging->console
Run the turtle simulator , Let the turtle hit the wall , Can be displayed RQT Display the printed log information

The first column below
severity Represents the log level , It is divided into debug info warn error fatal, The more to the right, the higher the level , Click a column to cancel the display of the level information

The second column below
Search log information keywords

RQT Management topics
Before, we posted the topic through the command line .RQT It can be published quickly , Change the topic
Plugins->Topics->message publisher
Click the plus sign to create a new topic , Topic selection turtle1/cmd_vel, The message type is automatically recognized as Twist
You can click to modify parameters in the interface , Checking this topic will realize the release , modify Freq You can change the release frequency

RQT Request service
RQT You can also request services , choice Plugins->services->service caller
Double click to edit parameters , Click on call Key will request service , The server-side response will be printed below .
Here we use /spraw（ Generate turtle service ） For example

RQT Automatic drawing
choice Plugins->visualization->plot Enter drawing
stay Topic Select the topic information to be drawn , Then the image will be automatically updated

Display the node relationship image
Plugins->introspection->Node Graph
You can display the node diagram