5 ms·

Watching the video I'm not sure I would have been able to stop in time. There's like a quarter second between first seeing the truck and slamming into it.

chemeng 5y ago
There’s little way to tell from the video. Human eyes have much higher dynamic range than typical video cameras. What the video shows is not likely representative of what your eyes would have seen.
- cryptonector 5y ago
  Watching the video a few times and knowing after the fact the first frame in which you can see something there, there's 4+ seconds to react. From the first indication of something being wrong (oncoming traffic headlamp occlusion) there's even more time (at least 7s). A sober, awake driver would have had "much higher dynamic range" as you put it, not only in their eyesight, but also in their acuity, and would have been able to come to a full stop without hitting the truck at all, much less hitting it at high speed.
  - labcomputer 5y ago
    With respect, while I broadly agree that a good driver could significantly mitigate the impact, I think you're looking at this with too much hindsight. 1. Even a sober, awake driver glances down to confirm their speedometer and scan their fuel gauge, check engine light, tire pressure, etc. 2. A sober, awake driver should be scanning the road along and beside the projected vehicle path. But they doesn't necessarily mean the would be looking in the direction of the occluded headlights at the very first instant they tell of a crashed car. 3. A sober, awake driver has to process what they see. 4. A sober, awake driver still has a good 0.2 to 0.25 second reaction time. 5. I actually do look for occluded lights when driving at night, but my experience talking about this with others in person is that this is a totally foreign concept. In other words, you know where and how and when to look for the obstruction because you've watched the video a few times. This is sort of like the Air France 447 flight or the Boeing 737 Max trim problem. If someone tells you exactly what kind of scenario you're going to face, how to handle it and approximately when you'll face it: you can win every time. 100% of pilots who were briefed on the specifics of AF447 avoided crashing the sim. Same for the 737 Max. Yet, hundreds of people are dead because pilots in actual cockpits, who were not given prior notification failed to act correctly.
ncallaway 5y ago
I think it's pretty likely that a human driver would have collided with the truck. A major difference is that (from watching the uncompressed footage), a human driver would likely have stomped on the breaks before impact. That last minute breaking could make a world of difference. A collision at 75 mph has a lot more energy (4.5x ish) than a collision at 35 mph. So every 1/10s of breaking will do a lot to reduce the damage of the impact. That's one of my concerns about driverless vehicles that I want to see the statistics on. I have a hunch that automation will reduce the absolute number of impacts, but may lead the impacts that remain could be higher energy impacts, because they result from a classification error.
avereveard 5y ago
dodging sudden obstacle is not something one usually does with higher level reasoning. if you fullscreen the better quality version from streamable and immerse in the situation, while the truck is hard to spot, brain can definitely see something is occluding road painting and other cars light. in person one might not realize a truck is there, but brain would probably think "something not right" and alert senses maybe even reflexively release pressure on the accellerator, so that when higher level consciousness makes out the truck, body is primed to act.

chemeng 5y ago

There’s little way to tell from the video. Human eyes have much higher dynamic range than typical video cameras. What the video shows is not likely representative of what your eyes would have seen.

cryptonector 5y ago
Watching the video a few times and knowing after the fact the first frame in which you can see something there, there's 4+ seconds to react. From the first indication of something being wrong (oncoming traffic headlamp occlusion) there's even more time (at least 7s). A sober, awake driver would have had "much higher dynamic range" as you put it, not only in their eyesight, but also in their acuity, and would have been able to come to a full stop without hitting the truck at all, much less hitting it at high speed.
- labcomputer 5y ago
  With respect, while I broadly agree that a good driver could significantly mitigate the impact, I think you're looking at this with too much hindsight. 1. Even a sober, awake driver glances down to confirm their speedometer and scan their fuel gauge, check engine light, tire pressure, etc. 2. A sober, awake driver should be scanning the road along and beside the projected vehicle path. But they doesn't necessarily mean the would be looking in the direction of the occluded headlights at the very first instant they tell of a crashed car. 3. A sober, awake driver has to process what they see. 4. A sober, awake driver still has a good 0.2 to 0.25 second reaction time. 5. I actually do look for occluded lights when driving at night, but my experience talking about this with others in person is that this is a totally foreign concept. In other words, you know where and how and when to look for the obstruction because you've watched the video a few times. This is sort of like the Air France 447 flight or the Boeing 737 Max trim problem. If someone tells you exactly what kind of scenario you're going to face, how to handle it and approximately when you'll face it: you can win every time. 100% of pilots who were briefed on the specifics of AF447 avoided crashing the sim. Same for the 737 Max. Yet, hundreds of people are dead because pilots in actual cockpits, who were not given prior notification failed to act correctly.

ncallaway 5y ago

I think it's pretty likely that a human driver would have collided with the truck. A major difference is that (from watching the uncompressed footage), a human driver would likely have stomped on the breaks before impact. That last minute breaking could make a world of difference. A collision at 75 mph has a lot more energy (4.5x ish) than a collision at 35 mph. So every 1/10s of breaking will do a lot to reduce the damage of the impact. That's one of my concerns about driverless vehicles that I want to see the statistics on. I have a hunch that automation will reduce the absolute number of impacts, but may lead the impacts that remain could be higher energy impacts, because they result from a classification error.

avereveard 5y ago

dodging sudden obstacle is not something one usually does with higher level reasoning. if you fullscreen the better quality version from streamable and immerse in the situation, while the truck is hard to spot, brain can definitely see something is occluding road painting and other cars light. in person one might not realize a truck is there, but brain would probably think "something not right" and alert senses maybe even reflexively release pressure on the accellerator, so that when higher level consciousness makes out the truck, body is primed to act.