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by ModernMech 265 days ago
100% it would have. One of the main things the LiDAR system does is establish a "ground plane", which is the surface on which the car is expected to drive. Any hole or protrusions in that plane stick out like a sore thumb to a LiDAR system, you'll be able to see it in the raw data without much of a feature detector, so detecting them and reacting is fast and reliable.

Contrast with Tesla's "vision-only" system, which uses binocular disparity along with AI to detect obstacles, including the ground plane. It doesn't have as good a range, so with a low- profile object like this it probably didn't even see it before it was too late. Which seems to me a theme for Tesla autonomy.
2 comments
xnx 265 days ago
In addition to detecting the object, Waymo has to make some determination about the material. Rigid heavy metal = slam on the brakes and/or swerve. Piece of tire or plastic bag = OK to run over if swerving or hitting the brakes would be more dangerous. Really hard problem that they're concerned about getting right before they open up highway driving.
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ModernMech 265 days ago
LiDAR is also good for that because you can measure light remission and figure out how much of the LiDAR energy the material absorbed. Different materials have different remission properties which can be used to discriminate. Which is a compounding advantage because we tend to paint road line markers with highly reflective paints. This makes line markers blindly obvious to a LIDAR.
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Der_Einzige 265 days ago
Elon's Musk believes that sensor fusion doesn't work and is a fake science.

This is why FSD is still shit in late 2025 and drives like it's drunk.

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