What is ROS 2?
ROS 2 is the widely used open-source framework for writing robot software. Despite the name, it is not an operating system but a collection of middleware, tools, and conventions that let the many parts of a robot, perception, planning, control, and more, run as separate components and exchange data through a common publish-subscribe system. It is the second generation of ROS, redesigned for reliability, real-time use, and production deployment.
Because so much of the robotics world builds on it, ROS 2 has become a de facto standard for how robot components talk to each other.
Key takeaways
- ROS 2 is an open-source framework and middleware for robot software.
- Components communicate through a publish-subscribe messaging system.
- It is a de facto standard across robotics research and industry.
How it works
Robot functionality is split into nodes that publish and subscribe to named topics, so a camera node might publish images that a perception node consumes. ROS 2 handles discovery, message passing, and timing across these nodes, and it standardizes how sensor streams are represented. Recorded runs are commonly saved to bag files, with MCAP now the default recording format, so data can be replayed and analyzed later.
Why it matters
ROS 2 is the connective tissue of modern robotics, which means the data that physical AI teams work with, from sensor streams to logs, very often arrives in its formats. Understanding it clarifies how robot data is produced, transported, and recorded, which is where formats like rosbag and MCAP come in.
Frequently asked questions
Is ROS 2 an operating system?
No. Despite the name, it is a framework and middleware that runs on top of a normal operating system to coordinate robot software components.
How is robot data recorded in ROS 2?
Runs are saved to bag files for later replay and analysis, with MCAP now the default recording format for ROS 2 bags.
Related terms