ignore measurements outside lidar range

[981213]

According to the comment in sensor_msgs/LaserScan, values < range_min or > range_max should be discarded.
Without this, scan matching will fail for lidars publishing 0 for invalid measurements.

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Basic Info

Info	Please fill out this column
Primary OS tested on	Ubuntu 22.04 / ROS2 Humble
Robotic platform tested on	My DIY robot with LeiShen Lidar

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Description of contribution in a few bullet points

• Don't add a point to UnfilteredPoingReadings when the range reading is outside lidar range.

[SteveMacenski]

slam_toolbox/lib/karto_sdk/include/karto_sdk/Karto.h

Line 3948 in 2f869c0

m_pRangeThreshold->SetValue(math::Clip(rangeThreshold, GetMinimumRange(), GetMaximumRange()));

The rangeThreshold is always less than GetMaximumRange so this is already true. You can revert these changes

[SteveMacenski]

Why not using that InRange line that was there before math::InRange(rangeReading, pLaserRangeFinder->GetMinimumRange(), rangeThreshold)? This seems to remove the far-check

[981213]

I moved the filtration outside karto_sdk in the latest iteration. The scan matching is fixed in both the old and this version, but loop closure still doesn't seem right with my half-blocked lidar.

I placed a second lidar on top of the half-blocked one to do some comparison. Here's my robot setup:

With async slam node, the top lidar and all the default configuration, it works perfectly:

But here's the result using the bottom one:

I wrote the lidar driver myself: https://github.com/981213/ls01_ros2 and the blocked measurements are set to 0 with memset in my code.

It would be great if someone can give me some suggestions on debugging.
Here's the ros2 bag for the test above.
rosbag2_2023_04_04-14_16_58.zip

/scan is the half-blocked lidar and /scan2 is the one on top.
The missing lidar transform:

ros2 run tf2_ros static_transform_publisher 0.03 0.0 0.1415 0 0 0 base_footprint laser_link

[981213]

Fixed with the latest commit, but I'm not sure if it's the correct fix because I haven't actually understood how ScanMatcher works yet.

edit: dropped this. I should simply lower the threshold in config file instead.