rqt

rqt is a Qt-based framework for building graphical user interfaces in the Robot Operating System (ROS). It provides a modular, plugin-driven environment that hosts a collection of tools for debugging, visualization, and interaction with ROS nodes, topics, services, and parameters. Plugins can be developed and loaded into a single rqt application to extend its functionality.

The architecture centers on a host application (rqt_gui) and a plugin API. It supports both C++ and Python plugins (via rqt_gui_cpp and rqt_gui_py) and uses a plugin manager to load and lay out panels within a main window. The rqt ecosystem is organized into packages such as rqt_common_plugins, which bundle widely used tools.

Commonly used plugins include rqt_plot for plotting time-series data; rqt_graph for visualizing the ROS computation graph of nodes and topics; rqt_console for displaying ROS log messages; rqt_reconfigure for dynamic_reconfigure-based parameter tuning; rqt_tf_tree for TF visualization; rqt_bag for working with rosbag data; and rqt_topic for inspecting publishers and subscribers. Additional plugins support topic monitoring, message inspection, parameter editing, and more.

Usage typically involves launching the rqt GUI from a ROS environment. Users can start the host with the command rqt (or rosrun rqt_gui rqt_gui) and then enable desired plugins via the Plugins menu or a plugin loading mechanism. Layouts can be saved and restored for repeated workflows.

Development and community: rqt is maintained as part of the ROS tooling ecosystem, with plugins contributed by end users and organizations. It emphasizes rapid prototyping of GUI tools and integrates with standard ROS tooling and workflows.