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Lane following isn't the hard part of self driving cars. I wouldn't say it's trivial, but it's a minor detail compared to everything else that also needs to wor
by sgtnoodle 4y ago
Lane following isn't the hard part of self driving cars. I wouldn't say it's trivial, but it's a minor detail compared to everything else that also needs to work reliably 99.9999% of the time.
Such infrastructure might help make cheaper lane-keep assist as standard options I guess, but at the speeds where it matters for safety, you need significant look-ahead on the trajectory rather than just lateral position error.
I suppose you could go crazy and embed some sort of NFC into the road, so that it can communicate the lane geometry. It could probably even be done cleverly, perhaps by embedding multiple nails and encoding curvature in their spacing, or maybe in the orientation of the magnetic flux itself. All that to avoid some front facing cameras and image processing, though, that can also be used to detect other cars and pedestrians.
- fastball 4y agoDo you need everything to work reliably 99.9999% of the time? Is that the reliability rating of human drivers?
- Retric 4y agoDepnds on how you count. If you consider every ~5 seconds you could have an accident, and a minor or worse accident happens once every 2,000 to 20,000 hours of driving that’s 99.99993% to 99.999993% reliability. On the other hand if you start talking per trio then we aren’t even close to that.
- fastball 4y agoWhy in the world would you count in 5 second intervals? If the measure is accidents per hour you don't then divide it by 5s. Reliability with 1 accident per 2k hours would be 99.95%. Reliability for 1 accident per 20k hours is 99.995%.
- Retric 4y agoFive seconds seems roughly how long it would take for really bad choices to cause an accident. In heavy traffic you can cause an accident by steering into a car in under a second. I am sure someone has had two independent accidents in under a minute. An hour on the other hand is completely arbitrary, why not a day or a minute?
- sgtnoodle 4y agoAny fixed timespan chosen to analyze risk is arbitrary, and you can convert between timespans using probability math. I'd say it's typical to choose the average "mission" length, because that's the most relevant to the purpose. For a self driving car, an hour would make sense. For the first stage of a rocket, 5 minutes. You don't ride in a car appreciating every 5 seconds that you haven't crashed yet, do you? Maybe if it's a taxi ride in Los Angeles! For a system that isn't "mission" oriented, you would probably think more in terms of mean time between failure.
- saltcured 4y agoYou're trying to talk about system reliability as a whole, while the others are talking about reliability of individual decisions or event handling. It's like the difference between talking about all-causes mortality versus the reliability of a bullet proof vest. Some don't buy that the vest is more reliable when we are not being shot.
- Retric 4y agoThe average American only drives ~35 miles per day. 1 hour may represent the average time driven per day but it’s much longer than the average trip length. Which doesn’t mean it’s a bad point of comparison but distance seems like the more common metric. Failure intervals generally use multiple different metrics depending on context. You see statistics for fatalities per year or per passenger mile as both being relevant depending on the context. A life insurance company and a car insurance company would focus on different statistics. The natural comparison for AI seems to be each individual situation. With City and Highway driving being different enough to be considered separately. In that context ~5 second intervals seem fairly natural because the car who accurately identified everything 0.001 seconds ago is probably going to avoid maying a major mistake for a few seconds. In much the same way a human driver can blink or look at a reed view mirror without significant risk.
- spookie 4y agoA single person might die, go to the hospital, or even go to jail depending on the accident. But if it's the car's software fault... Who gets blamed? Bear in mind we are trying to make this economically sustainable.
- fastball 4y agoPresumably the company making the car/software/hardware – whichever part is at fault. If one company is making all three (Tesla) it's pretty easy.
- hansvm 4y agoEven assuming one "event" per mile that needs to be handled satisfactorily (pothole, pedestrian, inconsistent embedded reflectors, chipped or graffitied sign, ....), 99.9999% is about the same reliability as the rate that human drivers crash in the US, and fatal crashes are around 100x less common. If, as in this comment thread, self-driving cars are being proposed as a solution to the deaths caused by human ineptitude then 99.9999% seems like an absolute bare minimum for reliability.
- fastball 4y agoWell in terms of fatalities, FSD actually has a 100% reliability rating, so presumably it's ok for it to be deployed, right?
- hansvm 4y agoNot really: - All FSD miles put together are still only 1/3 of the average miles needed to generate a fatal crash using a human driver. - The vast majority of those miles are in ideal conditions. - A cursory glance indicates there have been 15 FSD-induced fatalities.
- fastball 4y ago- Fair point, guess we will see in the next 60m miles, which by the sounds of it will be in the next few months. - Tesla's FSD in particular (being an entirely vision-based system) likely operates in less-than-ideal conditions much more often than competitors. - Where are you finding the "15 FSD-induced fatalities" stat?
- hansvm 4y ago- Another 60m miles will be suggestive, but you need at least 2x-3x the ordinary fatality mile count to even have a 90% confidence that the results weren't a fluke. - Tesla's FSD might operate in less-than-ideal conditions more often than competitors, but I'd posit that the typical human driver operates in much less ideal conditions than FSD. Humans are explicitly instructed to not enable it in sketchy scenarios and to be fully attentive when it's in control, and performance in that environment is at best an upper bound on what you might expect if deployed more widely. - I skimmed the stats from https://www.tesladeaths.com https://www.tesladeaths.com and was hoping Cunningham's law would kick in if that was too far off base.
- bobthepanda 4y agoGiven that road departments often have a hard time keeping paint fresh I have low hopes of nails faring much better. Some roads get their next resurfacing in timespans measuring decades.
- ticviking 4y agoI've found the folks forget just how HUGE the USA is. It might be possible to do this in a few core urban areas, but out in the hinterlands where there's nothing but cropland that feeds the core many roads are maintained only when they condition of the road causes serious damage.
- bobthepanda 4y agoUrban areas are not hot either. Roads are pretty consistently underfunded in most of them, and are in disrepair due to heavy usage, frost issues, etc. none of which is very kept up with due to the sheer size of urban road networks.