-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Reaction time required to avoid Florida crash?
- Thread starter atr2016
- Start date
-
- Tags
- Autonomous Vehicles
stopcrazypp
Well-Known Member
There's something a lot of you didn't consider. According to the truck driver's statements to the media, he paused for a car that was before the Tesla, but after he saw the Tesla coming, he floored it (I believe this was mentioned in a Reuter's report, although for some reason that report had been edited afterwards to remove that part, I'm guessing from request by his lawyer). The truck driver also indicated he saw the Tesla moving from the left lane to the right lane (this part had not been verified by Tesla or the investigators yet).
It could be possible the Tesla driver thought the truck would wait for him (given the Tesla driver had the right of way) and decided to pass on the right. The truck was likely already pulled into the turn lane and passed the median if it was waiting for the car before to pass. This would greatly reduce the amount of time the Tesla driver would have to react.
From another thread, passing on the right seems to be a natural reaction to a left turning car in the oncoming lane (even a moving one), even though logically going to the left may make more sense (so you pass behind the car). I think it is a similar instinct to how when people have a vehicle approaching from behind, they run forward and parallel to the vehicle path to try to escape it, even though it makes more logical sense to run perpendicular to the vehicle path.
It could be possible the Tesla driver thought the truck would wait for him (given the Tesla driver had the right of way) and decided to pass on the right. The truck was likely already pulled into the turn lane and passed the median if it was waiting for the car before to pass. This would greatly reduce the amount of time the Tesla driver would have to react.
From another thread, passing on the right seems to be a natural reaction to a left turning car in the oncoming lane (even a moving one), even though logically going to the left may make more sense (so you pass behind the car). I think it is a similar instinct to how when people have a vehicle approaching from behind, they run forward and parallel to the vehicle path to try to escape it, even though it makes more logical sense to run perpendicular to the vehicle path.
This was not a reaction time accident, this was a not paying attention accident.
I might agree reaction time played a role IF there had been any attempt by the driver to either brake, steer, or even duck (in which case he would likely be alive).
What evidence is there that the driver was not paying attention? IF half of what @stopcrazypp described is true, that would seem to disprove such a presumption. That was precisely what I was trying to uncover with this discussion, so thank you all for chiming in.
EV-lutioin
Active Member
Correct me if I am wrong, but I think most state laws deem any vehicle that crosses a road in front of another right of way vehicle, at fault.
"It could be possible the Tesla driver thought the truck would wait for him (given the Tesla driver had the right of way) and decided to pass on the right. The truck was likely already pulled into the turn lane and passed the median if it was waiting for the car before to pass."
Tesla has stated that AP was active at the time of impact. If there had been any attempt at steering the car, AP would have canceled, which it did not according to TM. I think it is safe to say that the Tesla proceeded directly into the truck with no changes in course or speed.
Tesla has stated that AP was active at the time of impact. If there had been any attempt at steering the car, AP would have canceled, which it did not according to TM. I think it is safe to say that the Tesla proceeded directly into the truck with no changes in course or speed.
I only see two alternatives.
If he was paying attention, the only explanation I see is that he had a medical issue that prevented him from steering, braking or ducking.
The simpler explanation is he wasn't paying attention.
Perhaps we will get more information with the continuation of the NHTSA investigation.
cantdecide
Member
Yep, the critical thing is not how far away the driver could see the truck, but when the truck was visibly crossing the lanes of oncoming traffic.
The truck was likely only in the Tesla's lane for about 3 seconds before the crash... The car reportedly hit near the front of the trailer... A truck only takes about that long to cross a lane. That indicates a maximum distance of about 90 meters (270 ft) before the driver possibly have noticed the truck encroaching. Given one second to react and move a foot to the brake and 170ft to stop and you have a situation where the driver may or may not have been able to stop if the driver had been paying attention. If an attentive driver had been there and happened to glance at the speedometer at the wrong moment, they would have crashed.
CHG-ON
Still in love after all these miles
It's flat as a pancake on that maps image and another aerial shot that has been posted! 18-24" of height won't make a difference. It certainly seems to me, the uninformed peanut gallery commenter, that there should have been plenty of time to react if the driver had been watching the road.
I wonder, as mentioned by @Zythryn, if perhaps the driver had an emergency where he lost consciousness. I am also perplexed that the radar did not catch the truck, unless it was looking under it. I'm not sure that I buy that the camera did not see it. But I'll go with Tesla on that for now.
79 MPH on a road with cross traffic, even limited, is a pretty good clip. I'm not sure I would use AP at that speed. I hope that all other drivers use this as a motivator to both keep their eyes on the road at all times and to not completely put their lives completely in the hands of a computer. Based on my PC at work, I'd be a goner.
I really do hope that it happened so fast that the driver didn't suffer. Such a tragic event. My heart goes out to his loved ones.
Last edited:
stopcrazypp
Well-Known Member
Tesla did not say however that the driver did not use the lane change feature of autopilot. If he did, then that would be consistent with what the truck driver saw and also consistent with the continued activation of autopilot (presumably auto steer).
Also, another subtlety is that TACC does not cancel on steering input, so technically "autopilot" may still be considered active even though autosteer was cancelled.
Even if all your numbers are correct, in this case, the brakes were never applied.
I'm not saying the accident was avoidable, I am saying even a somewhat alert driver would have at least had time to hit the brakes. The driver never applied the brakes.
There's a significant change of elevation as you can see from this image which is 550 metres from where the truck would have been.
Google Maps
Look for the Lays delivery truck parked in the gas station sign on the right. That gives you a visual cue you can use to judge what might be visible to the driver as he approached.
In any case, I agree with you that whatever the visibility is like there, it's clear to me the driver wasn't looking out of the windscreen for whatever reason, because even with the dip in the road there would have been enough time to react. Maybe the final report will explain everything, but I'm not so sure.
Last edited:
Jbailey
Member
The truck was making a left turn so it had to be moving slow and trucks don't have the greatest of pickup. He hit it behind the cab so it did not just suddenly dart in front of him. He was going 74 in a 65 so while speeding, not by that much.
Pretty common scenario...typically plenty of time to stop
With so many cars having crash mitigation technology, I hope this triggers the requirement of barriers under trailers. I see this on about one out of 3 now. I think the car would have alerted him and or slowed down if this barrier were present as opposed to open space under the truck.
Truck drivers do this stuff all the time...slowly edge out in front of oncoming cars rather than wait for a long interval.
Pretty common scenario...typically plenty of time to stop
With so many cars having crash mitigation technology, I hope this triggers the requirement of barriers under trailers. I see this on about one out of 3 now. I think the car would have alerted him and or slowed down if this barrier were present as opposed to open space under the truck.
Truck drivers do this stuff all the time...slowly edge out in front of oncoming cars rather than wait for a long interval.
I just returned from a trip on a VERY similar road with a 70 mph limit. Everyone was driving 74-76 mph. I observed semi-trucks and other vehicles pulling out into the median. On the whole trip I was thinking about this very accident (and often discussing it with my passengers). At one point during the trip I was up close to a semi-truck (at a 4-way stop so not at high speed thankfully) right between the cab and rear wheels. It sure gives you a sick feeling, certainly not the same feeling I had watching Family Vacation:
