feat: Core MAPF Path Server, Plan Executor, and Visual Tooling

[arjo129]

Overview

Built on: ROS 2 Jazzy

This Pull Request introduces the foundational Multi-Agent Pathfinding (MAPF) trajectory generation, decoupled execution tracking, mock simulation scaffolding, and basic visual verification tools for the Next Generation RMF prototype.

By cleanly separating high-level conflict-free path planning from runtime trajectory execution, this architecture enables highly scalable fleet coordination, dynamic participant discovery, explicit progress signaling via safe zones, and rapid visualization.

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Architectural Components & Packages

1. Planning & Execution (Decoupled Pipeline)

• rmf_path_server: Core ROS 2 Rust planning node wrapping the MAPF backend (pibt). Implements asynchronous background planning. It also supports traffic dependency calculation which can then be used for dynamic safe zone grid allocation, traffic dependency visualization, footprint enforcement, and explicit waypoint release signaling by the rmf_plan_executor and dashboard.
• rmf_plan_executor: Runtime execution coordinator. Subscribes to generated multi-agent trajectories, manages dynamic participant tracking, and synchronizes real-time waypoint progress via explicit PlanRelease signaling.

2. Interactive Demos & Visual Tooling

• rmf_path_server_demo: An interactive web dashboard (HTML5/CSS3/VanillaJS) and scenario runner (demo.launch.py) allowing users to interactively spawn robots, click to assign goals, and observe dynamic conflict-free planning on a live HTML canvas. (More instructions Below)
• rmf_path_server_test: Provides tests to check the validity of the path tracking (via PlanRelease.msg). We also provide a small web-based visualer to debug test trajectories.

3. Simulation & Supporting Infrastructure

• rmf_mock_robot_sim: Lightweight Python simulation node modeling waypoint following behavior and publishing active robot state.
• rmf_participant_discovery: Extended participant lifecycle messages (onboarding/offboarding) supporting fleet discovery.

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Verification & Testing

Setup & Building

1. Import Workspace Dependencies (via .repos file)
   Create a workspace and import the required ROS 2 Rust and navigation dependencies using this setup.repos:

   mkdir -p rmf_ws/src
   cd rmf_ws
   vcs import src < setup.repos

2. Build the PR Packages
   Ensure you are at the workspace root inside the jazzy distrobox container, then build the relevant packages:

   colcon build --packages-select rmf_prototype_msgs rmf_participant_discovery rmf_path_server rmf_plan_executor rmf_mock_robot_sim rmf_path_server_demo rmf_path_server_test

Running Automated Integration Tests

Verify core scenario coordination and robust following behavior:

colcon test --packages-select rmf_path_server_test --event-handlers console_direct+

Running the Interactive Web Demonstration

path_server_smol.mp4

Launch the fully standalone path server dashboard:

ros2 launch rmf_path_server_demo demo.launch.py

1. Open http://localhost:8080 in your web browser.
2. Click Add Robot to drop active participants onto the canvas.
3. Select a robot and click a cell to place its goal.
4. Click Send Scenario to observe multi-agent trajectory generation and live execution progress.

Note: The visualizers are largely vibe-coded and meant to be used during development and debugging. I fully expect rmf-site to replace them in our first release. I would not personally bother with scrutinizing the quality of the code there.

Additional note: Currently mapf_post is pulled via git directly from the arjo/feat/more_efficient_checks branch.

We also don't introduce maps here as that is a whole other ticket of its own (See #12)

GenAI Use

We follow OSRA's policy on GenAI tools

• I used a GenAI tool in this PR.
• I did not use GenAI

Generated-by: Gemini-CLI

[SamuelFoo]

Thanks for the PR! Just some minor comments.

[SamuelFoo]

Is there any danger of this underflowing if the plan is empty?

This is probably a minor issue if the current plans seem to always produce one waypoint.

[arjo129]

Nice catch we should absolutely check this! Ive fixed it in 70e281e

[arjo129]

On a more serious note we should probably do more input validation, but that should ideally be a seperate PR.

[Copilot]

Pull request overview

This PR introduces a foundational ROS 2 Jazzy “path planning → execution” pipeline for the next-gen RMF prototype, including participant discovery utilities, a Rust MAPF path server + executor, a Python mock robot simulator, launch-test integration coverage, and web-based visualization/demo tooling.

Changes:

• Added rmf_path_server (Rust) with a decoupled worker model (discovery vs destinations) and a PIBT-based planner backend.
• Added rmf_plan_executor (Rust) to track execution progress, publish PlanRelease, and generate SafeZone costmaps.
• Added rmf_participant_discovery (Rust lib), rmf_mock_robot_sim (Python), rmf_path_server_test (launch tests + trajectory visualizer), and rmf_path_server_demo (web dashboard + HTTP/SSE spawner).

Reviewed changes

Copilot reviewed 54 out of 56 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
.gitignore	Adds ignore patterns (currently includes source-file entries that should be removed).
README.md	Documents workspace setup, build, tests, and demo usage.
discourse/1-topics-interfaces.md	Adds design document for topic/interface taxonomy.
discourse/2-traffic-management-interfaces.md	Adds Discourse link header to traffic management interfaces document.
path_server/README.md	Documents path server folder and demo launch.
path_server/rmf_path_server/.gitignore	Ignores Rust target/ output.
path_server/rmf_path_server/Cargo.toml	Declares Rust deps for path server (currently unpinned / git branch-based).
path_server/rmf_path_server/package.xml	ROS package manifest for the Rust path server node.
path_server/rmf_path_server/src/lib.rs	Implements path server workers, background planning, plan publication, and discovery wiring.
path_server/rmf_path_server/src/main.rs	Starts the path server node and spins executor.
path_server/rmf_path_server/src/planner.rs	Defines MapfPlanner trait plus PIBT-based planner implementation.
path_server/rmf_plan_executor/.gitignore	Ignores Rust target/ output.
path_server/rmf_plan_executor/Cargo.toml	Declares Rust deps for plan executor (currently unpinned / git branch-based).
path_server/rmf_plan_executor/package.xml	ROS package manifest for plan executor.
path_server/rmf_plan_executor/src/lib.rs	Implements execution tracking, PlanRelease, and safe-zone allocation/costmap publication.
path_server/rmf_plan_executor/src/main.rs	Runs executor + discovery wiring for per-robot subscriptions.
path_server/rmf_path_server_demo/README.md	Documents demo dashboard usage.
path_server/rmf_path_server_demo/launch/demo.launch.py	Launches path server + spawner + executor for demo.
path_server/rmf_path_server_demo/package.xml	ROS package manifest for demo tooling.
path_server/rmf_path_server_demo/resource/rmf_path_server_demo	Ament resource index marker.
path_server/rmf_path_server_demo/setup.cfg	Python package install script dirs.
path_server/rmf_path_server_demo/setup.py	Installs demo Python package and web assets.
path_server/rmf_path_server_demo/rmf_path_server_demo/__init__.py	Python package init.
path_server/rmf_path_server_demo/rmf_path_server_demo/robot_spawner.py	HTTP/SSE bridge that spawns mock robots and publishes discovery/destinations.
path_server/rmf_path_server_demo/www/app.js	Dashboard logic (SSE stream, robot interactions, rendering).
path_server/rmf_path_server_demo/www/index.html	Dashboard HTML layout and dependencies.
path_server/rmf_path_server_demo/www/style.css	Dashboard styling.
path_server/rmf_path_server_test/.gitignore	Ignores pytest cache and bytecode in tests.
path_server/rmf_path_server_test/README.md	Documents launch tests and the trajectory visualizer usage.
path_server/rmf_path_server_test/package.xml	ROS package manifest for tests (missing some test dependencies).
path_server/rmf_path_server_test/resource/rmf_path_server_test	Ament resource index marker.
path_server/rmf_path_server_test/setup.cfg	Python package install script dirs.
path_server/rmf_path_server_test/setup.py	Installs test package and visualizer CLI entry point.
path_server/rmf_path_server_test/rmf_path_server_test/__init__.py	Python package init.
path_server/rmf_path_server_test/rmf_path_server_test/visualize.py	Standalone trajectory CSV web visualizer.
path_server/rmf_path_server_test/test/test_copyright.py	Ament copyright lint test.
path_server/rmf_path_server_test/test/test_flake8.py	Ament flake8 lint test.
path_server/rmf_path_server_test/test/test_pep257.py	Ament pep257 lint test.
path_server/rmf_path_server_test/test/test_path_server_follow.py	Integration test for following/collision avoidance behavior.
path_server/rmf_path_server_test/test/test_path_server_scenario.py	Integration test for dynamic redirection + scenario behavior.
rmf_participant_discovery/.gitignore	Ignores Rust target/ output.
rmf_participant_discovery/Cargo.toml	Rust crate manifest for participant discovery helper.
rmf_participant_discovery/package.xml	ROS package manifest for participant discovery crate.
rmf_participant_discovery/src/lib.rs	Provides ParticipantTracker + generic discovery subscription helper and tests.
rmf_mock_robot_sim/README.md	Documents mock robot simulator behavior (needs topic corrections).
rmf_mock_robot_sim/package.xml	ROS package manifest (currently contains TODO placeholders).
rmf_mock_robot_sim/resource/rmf_mock_robot_sim	Ament resource index marker.
rmf_mock_robot_sim/setup.cfg	Python package install script dirs.
rmf_mock_robot_sim/setup.py	Python package manifest (currently contains TODO placeholders).
rmf_mock_robot_sim/rmf_mock_robot_sim/__init__.py	Python package init.
rmf_mock_robot_sim/rmf_mock_robot_sim/mock_robot_sim_node.py	Mock robot simulation node publishing odom/progress and following plans/releases.
rmf_mock_robot_sim/test/test_copyright.py	Ament copyright lint test.
rmf_mock_robot_sim/test/test_flake8.py	Ament flake8 lint test.
rmf_mock_robot_sim/test/test_mock_robot_sim.py	Launch test validating mock robot behavior with plan/release/progress.
rmf_mock_robot_sim/test/test_pep257.py	Ament pep257 lint test.
rmf_prototype_msgs/msg/Participant.msg	Minor formatting change (trailing blank line).

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[arjo129]

Lets open an issue to handle this in the future.

[mxgrey]

I just have a few small follow-up remarks on the build instructions. Other than that, I'll be happy to merge this soon.

[mxgrey]

When and how do the message packages get built under these build instructions?

I think we need the user to install colcon-cargo and colcon-ros-cargo to generate the config file with the patches, don't we? As of Noble, I believe this still requires users to do pip install --break-system-packages ... which feels icky, but currently there doesn't seem to be a good way around it.

Another option might be to provide the user with a premade .cargo/config.toml containing the patches and give them a curl command to put it in their workspace. That would spare them from needing --break-system-packages.

[arjo129]

1243d2b

[mxgrey]

The CPU throttle is a very good point for why we should just stick with a 10Hz idle loop. Like you said, we could still do debouncing with a reactive system, but the added complexity isn't worth the extremely minor performance benefits (if there would even be any performance benefits at all).

[mxgrey]

FWIW I could change this to xml/yaml if those are preferred.

I don't have a strong personal opinion, I was mostly curious. I think .launch.xml is more broadly familiar, easier to understand, and easier to write in most cases. Even though I don't generally care for .xml, I think people get easily confused by .launch.py's declarative structure.

Does <include> work across .launch.xml and .launch.py? I think most of our user-base will prefer .launch.xml, so if we make anything that we want to be includable by downstream launch files, we should make sure .launch.xml files can include them.

[arjo129]

For whatever reason I cant re-open this pull request to target the correct branch when I deleted the base branch. Ive opened #17 to continue development.