feat(ouster): add native Ouster lidar driver

[guthabharadwaj]

Adds a new nebula_ouster package providing native support for Ouster OS-0, OS-1, and OS-2 sensors with any beam count (32/64/128). Decodes Ouster UDP packets directly without depending on ouster-sdk, supporting LEGACY, RNG19 single-return, and RNG19 dual-return profiles, plus IMU output.

PR Type

• New Feature

Related Links

• Related PR: feat(Ouster): implement nebula's Ouster port as a submodule #436 (alternative Ouster integration using ouster-sdk)
• Tracking issue: Do you have plans to support Ouster sensor #212

Description

Adds native Ouster LiDAR support to Nebula without depending on ouster-sdk, keeping the dependency footprint minimal and consistent with how other vendors (Hesai, Velodyne, Robosense) are implemented.

Packages added:

• nebula_ouster_common — sensor configuration types, packet profile enums, per-beam calibration structures
• nebula_ouster_hw_interfaces — UDP socket handling for lidar and IMU packet streams
• nebula_ouster_decoders — packet parsing for LEGACY, RNG19 single-return, and RNG19 dual-return profiles; per-beam XYZ lookup table generation; metadata (sensor_info) parsing
• nebula_ouster — ROS 2 wrapper node, launch files, example YAML config, IMU publisher

Key design choices:

• No ouster-sdk dependency — all packet parsing, projection math, and metadata handling implemented natively
• Supports any beam count (32/64/128) by driving geometry from the sensor's sensor_info JSON at runtime rather than compile-time constants
• Dual-threaded, mutex-free architecture for lidar and IMU packet paths
• Works with live sensors and offline rosbag replay

Also updated:

• Top-level package registration to include the new packages
• .gitignore for Ouster-specific build artifacts

Review Procedure

1. Build: colcon build --packages-up-to nebula_ouster --symlink-install
2. Live sensor test (OS-0/OS-1/OS-2, any beam count): ros2 launch nebula_ouster ouster_launch_all_hw.xml — verify /pointcloud_raw and /imu/data publish at expected rates and point cloud renders correctly in RViz2.
3. Offline test: replay a rosbag containing raw Ouster UDP packets and confirm point cloud reconstruction.
4. Config: see nebula_ouster/config/Ouster.param.yaml for an example configuration.

Remarks

• Happy to split this into smaller stacked PRs (common → hw_interfaces → decoders → ROS wrapper) if preferred for review. Opened as a single PR first to make the overall design visible before splitting.
• Unit tests not yet included — planning to mirror the decoder test pattern used by other vendors (recorded packet fixtures → assert point count, XYZ, timestamps, ring index). Will add based on reviewer guidance on scope.
• Happy to rebase onto a different base branch if needed.
• Tested against a physical OS-128 sensor integrated into the full Autoware preprocessing pipeline (driver → crop box filters → distortion correction → ring outlier filter) on ROS 2 Humble. Point cloud output validated in RViz.

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