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You are extremely misinformed. I'll go through the points one by one. > I thought these cars had lidar? Scale of rollout is a strategic imperative brought on

You are extremely misinformed. I'll go through the points one by one. > I thought these cars had lidar? Scale of rollout is a strategic imperative brought on by the advantage of massive datasets. Lidar was very expensive relative to cameras. It also didn't have the existence proof of human-level driving which vision has. Tesla opted not to use it. > I thought these cars had radar? Radar they did opt to use, since the sensors for it were cheap, but counterintuitively it ended up hurting performance. It has edge cases in which it is very wrong, for example when you go under an underpass radar gets confused and misreports the distance. This leads to very uncomfortable false positives, like slamming on the break while on a freeway, which could lead to brutal and horrifying death for the person behind you. Solving that effectively meant sensor fusion, but in practice the vision stack has a neural architecture which makes its reliability much greater than radars reliability. If you have two unreliable sensors you can combine them to get a better sensor. If you have an unreliable sensor and a reliable sensor, it makes more sense to just use the good sensor. They empirically validated that removing radar improved the systems performance. Then did so. Anecdotally, I haven't had a false-positive break check while going under an underpass since then. > Is it possible overloading of the CPU that can't keep up with the volume of data being given to it by all of the various inputs? Tesla's have dedicated chips which handle the self-driving workload. I believe these are more alike to GPUs then CPUs. The system doesn't have a problem handling the workload. > The radar should "see" things 160 metres away so regardless of whether the Tesla thought these were cars, shouldn't it still have seen them as obstructions and avoided them? Go to the actual incident and you watch the computer planned trajectory it is very clear that the planned route has the Tesla entering the center left turn lane directly ahead of it. There wasn't going to be a head on collision and if there was it wouldn't have been the Tesla's fault. If another vehicle hits you while you are in a central left turn lane preparing for a left turn, that is on them, not you. Also, in addition to being misleading, the video title is against the Hacker News guidelines; that wasn't the title of the video. That was a wrong but shocking description of the video which draws attention away from the actual issues: - There is a timestamp where it plans a bad route briefly. That is something to investigate and fix even if it didn't ultimately keep that route. - It also enters a lane with markings indicating that it shouldn't be entered. That is another serious issue that needs to be addressed.

JamesSwift 4y ago
> They empirically validated that removing radar improved the systems performance. Then did so. Anecdotally, I haven't had a false-positive break check while going under an underpass since then If the failure mode is well known and the system is advanced enough to interpret what it sees, why wouldn't it factor in that they are about to be in an underpass to adjust the reliability factors of the sensors? What sense does it make to completely remove the other sensor to avoid a possible-to-predict edge-case?
- JoshCole 4y ago
  If you rely on radar when you shouldn't rely on radar, people can die. So the answer to half your question is that even a minuscule probability of misidentification has intolerable consequences. If you rely on radar, because you can't rely on vision, people can also die. You are driving while blind to things like stop lights. Unless vision conditions improve it isn't safe to drive. Also there are going to be the same edge cases where radar failed, but now vision won't be able to compensate for them. Since radar can also fail by failing to detect something there, not just detecting something that isn't there, this is a fatality waiting to happen. In every other case, since the error bars are lower on vision than they are on radar, you ought to be relying on vision. Therefore, since in every conditional case in which driving is reasonable, vision is demanded, engineering effort is better directed toward vision than radar.
pr0zac 4y ago
>> Go to the actual incident and you watch the computer planned trajectory it is very clear that the planned route has the Tesla entering the center left turn lane directly ahead of it. There wasn't going to be a head on collision and if there was it wouldn't have been the Tesla's fault. Someone else posted an image in a different thread ( https://i.imgur.com/Hj6glgu.png https://i.imgur.com/Hj6glgu.png ) and its pretty clear the car's planned route was to move into the opposing traffic's lane which makes very little sense but would've 100% definitely made the accident the Tesla's fault.
- JoshCole 4y ago

JamesSwift 4y ago

> They empirically validated that removing radar improved the systems performance. Then did so. Anecdotally, I haven't had a false-positive break check while going under an underpass since then If the failure mode is well known and the system is advanced enough to interpret what it sees, why wouldn't it factor in that they are about to be in an underpass to adjust the reliability factors of the sensors? What sense does it make to completely remove the other sensor to avoid a possible-to-predict edge-case?

JoshCole 4y ago
If you rely on radar when you shouldn't rely on radar, people can die. So the answer to half your question is that even a minuscule probability of misidentification has intolerable consequences. If you rely on radar, because you can't rely on vision, people can also die. You are driving while blind to things like stop lights. Unless vision conditions improve it isn't safe to drive. Also there are going to be the same edge cases where radar failed, but now vision won't be able to compensate for them. Since radar can also fail by failing to detect something there, not just detecting something that isn't there, this is a fatality waiting to happen. In every other case, since the error bars are lower on vision than they are on radar, you ought to be relying on vision. Therefore, since in every conditional case in which driving is reasonable, vision is demanded, engineering effort is better directed toward vision than radar.

pr0zac 4y ago

>> Go to the actual incident and you watch the computer planned trajectory it is very clear that the planned route has the Tesla entering the center left turn lane directly ahead of it. There wasn't going to be a head on collision and if there was it wouldn't have been the Tesla's fault. Someone else posted an image in a different thread ( https://i.imgur.com/Hj6glgu.png https://i.imgur.com/Hj6glgu.png ) and its pretty clear the car's planned route was to move into the opposing traffic's lane which makes very little sense but would've 100% definitely made the accident the Tesla's fault.

JoshCole 4y ago