Unlike ROS 1, ROS 2 bag files do not store the schema of their messages alongside their actual data. This makes it impossible to parse certain ROS 2 messages in open source tools like PlotJuggler, as the necessary info may be unavailable.
To address this rosbag2 SQLite storage shortcoming, PlotJuggler lead developer @facontidavide added MCAP support in the time series visualization tool’s v3.6 release.
You can now store ROS 2 messages (with their schemas!) in completely self-contained MCAP files, and load them into PlotJuggler to be parsed and visualized without any issues.
We hope this expanded support helps more folks explore and analyze their ROS 2 data!