Re: "...a [Lidar] blind spot low to the ground all around the car."
"And that's the bit that's really, really hard. Is it a paper bag? Is it a brick? Is it a plastic or glass bottle? Is it something that fell off the back of a lorry that might cause damage or and old newspaper just blowing in the wind"
...and in the weird and wonderful real world of coincidences, I went out in the car a few hours after posting that and while driving had to avoid a claw hammer laying the road right where the wheels would normally be passing over. I've never seen one of those in the road before and it could have done serious damage either to the tyres or, if hit "right", the underside of the car, eg brake lines. Would an AV have seen it, recognised it for the danger it posed and avoided it?