Files

T

m5p3nc3r 0174cb599f Manage sllidar_ros2 as a git subtree and apply QoS fix

- Add m5p3nc3r/sllidar_ros2 fork as a git subtree at lidar/sllidar_ros2/
- Dockerfile now COPYs source from the workspace instead of cloning at
  build time; git is no longer a build dependency
- Set /scan publisher QoS to BEST_EFFORT (depth 2) for Nav2/RViz2 compat
- Add lidar/README.md documenting the subtree workflow
- Remove lidar/sllidar_ros2/ from .gitignore (no longer needed)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

2026-04-22 11:54:06 +00:00

2.8 KiB

Raw Blame History

RPLIDAR A1 — LIDAR Container

ROS 2 container for the Slamtec RPLIDAR A1, built on top of a fork of the official sllidar_ros2 driver.

How the build works

The driver source lives in lidar/sllidar_ros2/ as a git subtree of this repository. The Dockerfile copies it directly from the workspace — no network access is required at build time.

Workspace repo                Docker build
──────────────────────────    ──────────────────────────────────────────
lidar/sllidar_ros2/      ───> COPY lidar/sllidar_ros2/ src/sllidar_ros2/
(git subtree of fork)         colcon build --packages-select sllidar_ros2

The upstream fork is maintained at:

https://github.com/m5p3nc3r/sllidar_ros2

Development workflow

Pulling upstream changes into the workspace

git subtree pull --prefix=lidar/sllidar_ros2 sllidar_ros2 main --squash

This fetches the latest commits from the fork, squashes them into a single merge commit, and updates lidar/sllidar_ros2/ in the workspace.

Making local changes

Edit files inside lidar/sllidar_ros2/ as normal, then commit them to the workspace repo:

git add lidar/sllidar_ros2/
git commit -m "lidar: describe the change"

Pushing changes back to the fork

git subtree push --prefix=lidar/sllidar_ros2 sllidar_ros2 main

This replays only the commits that touched lidar/sllidar_ros2/ and pushes them to the fork's main branch.

First-time setup on a fresh clone

The subtree files are committed in the workspace repo, so a git clone of this repo is all that is needed — there is no separate step to initialise the subtree. To be able to pull or push to the fork later, add the remote:

git remote add sllidar_ros2 https://github.com/m5p3nc3r/sllidar_ros2.git

Changes relative to upstream

File	Change
`src/sllidar_node.cpp`	`/scan` publisher QoS set to `BEST_EFFORT` with depth 2. Required for compatibility with Nav2 and RViz2, which subscribe to `/scan` with `BEST_EFFORT`. The upstream default (`RELIABLE`) causes those consumers to receive no data.

The upstream Slamtec repository is at:

https://github.com/slamtec/sllidar_ros2

Published topics

Topic	Type	Description
`/scan`	`sensor_msgs/LaserScan`	360° laser scan, `BEST_EFFORT` QoS, depth 2

Device

The RPLIDAR A1 connects via USB serial at /dev/ttyUSB0 (default), 115200 baud. The container receives access to that device via the devices mapping in docker-compose.yml. To use a different port, set LIDAR_PORT in your .env file:

LIDAR_PORT=/dev/ttyUSB1

2.8 KiB Raw Blame History