GLIM ROS2 fails to create map using RoboSense RS-Airy LiDAR

[mahmood-ul-hasan]

🐞 GLIM ROS2 fails to create map using RoboSense RS-Airy LiDAR

Environment

• ROS2 Distribution: Humble
• LiDAR Sensor: [RoboSense RS-Airy](https://www.robosense.ai/en/IncrementalComponents/Airy)
• RoboSense SDK Version: v1.5.17

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🧩 Description

When running GLIM ROS2 with the RS-Airy LiDAR, the mapping node starts successfully but produces a distorted map — the LiDAR scans diverge infinitely instead of forming a proper 3D map. The process repeatedly prints timestamp synchronization warnings and fails to generate stable submaps.

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🧠 Observed Behavior (Logs)

Key warnings from the GLIM output:

[glim] [warning] init_T_world_imu is missing or malformed in JSON
[glim] [warning] per-point timestamps are not given!!
[glim] [warning] use pseudo per-point timestamps based on the order of points
[glim] [warning] large time gap between consecutive LiDAR frames!!
[glim] [warning] large time difference between points and imu!!

These warnings appear continuously, suggesting a timestamp synchronization mismatch between LiDAR and IMU data. As a result, the generated map is distorted and unstable.

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⚙️ Related LiDAR Node Output

RoboSense SDK logs indicate successful packet reception and decoding:

RSLidar_SDK Version: v1.5.17
lidar_type: RSAIRY
msop_port: 6699
difop_port: 7788
imu_port: 6688
use_lidar_clock: 1
wait_for_difop: 1
Send PointCloud To : ROS
PointCloud Topic: /rslidar_right/lidar_points
RoboSense-LiDAR-Driver is running.....

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🧩 Expected Behavior

GLIM should:

• Properly synchronize LiDAR and IMU timestamps
• Initialize mapping correctly
• Create stable submaps and a consistent global map from RS-Airy LiDAR input

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🖼️ Attachments

If required, I can provide:

• A short .rosbag2 dataset containing RS-Airy LiDAR + IMU topics for debugging

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