ROS 2

ROS 2 is a graph of processes that talk over typed interfaces. combeanie pins Jazzy (ROS_DISTRO=jazzy in flake.nix).

Concept	Analogy	When to use
Package	Library / crate with package.xml	Ships code, config, launch
Node	Long-running process with one job	Perception, world state, coordinator
Topic	Pub/sub stream	/joint_states, images, observations
Service	Request/response RPC	Reserve a lane, get a snapshot
Action	Long job with feedback + cancel	Restock a product; survey a lane
Launch	Process supervisor	Start sim + MoveIt + task stack together

Why it matters here

The restock pipeline is not one program. Benchmarks send a RestockProduct action goal; the coordinator talks to world-state services, MoveIt, and Gazebo adapters over topics. Debugging is graph debugging: ros2 node list, topic echo, action list.

This project

                    /restock_product (action)
                              │
                    restock_action_coordinator
                     │        │         │
          world_state svc   move_group   attachment / gripper topics
                     │
              world_state_node ← /perception/*_observations

Package	Owns
restocker_interfaces	.msg / .srv / .action
restocker_description	URDF/Xacro + geometry YAML
restocker_gazebo	World, spawn, GT + attachment
restocker_control	Controllers + telemetry
restocker_moveit_config	MoveIt / move_group
restocker_world_state	Semantic inventory authority
restocker_perception	RGB-D → observations
restocker_task_executor	Task SM, projector, surveys
restocker_reasoner	Optional advisory HTTP client
restocker_bringup	Composition launches
restocker_benchmarks	Scenario client / metrics

Public surface examples: /restock_product, /world_state/get_snapshot, /perception/object_observations, /restock_action_coordinator/status.

Composition entrypoint: ros_ws/src/restocker_bringup/launch/baseline.launch.py.

References

• Official docs: ROS 2 Jazzy, Basic Concepts
• Official docs: Nodes · Topics · Services · Actions
• Official docs: Understanding actions (CLI)
• Official docs: Launch
• This project: Package map · Task execution