There's a left-hand exit there because there's an interchange between freeways, and the HOV lane exits on the left, to enable free flowing HOV traffic to avoid merging through general traffic to get to a right exit.
At this interchange, I've seen lots of human drivers change between the exiting HOV lane and the continuing HOV lane (or vice versa) much later than is safe; presumably because they were surprised that their lane was exiting, or they noticed the exit too late, but didn't want to miss it. I haven't seen anyone drive in between the two lanes as if it was a lane, though; and usually the late lane changers are braking, not accelerating.
It is unfortunate that the crash attenuator wasn't reset. Looking at the docs for a similar attenuator[1], it seems like resetting is somewhat involved, and you'd need a trained and properly equipped repair crew to do it, even if the time required is not that much. Scheduling is probably an issue.
Thing is, a lot of exit lanes have white lines you have to cross, which I've wondered about as a driver. Usually you have to cross a white line to get into the hov lane, like an cloverleaf/onramp usually around a meter.
I've seen that as well and that only ever happens when the left most lane is also an exiting lane. It's not intuitive by any means but it's also consistent so if you know the rules and can see the road ahead, you'll be safe.
Chicago has a gated middle 2-lane express lane in the freeway. Gates go up on one side to allow traffic through, depending on traffic conditions, to force it one-way.
What I've never been sure about is how they guarantee no one is still traveling in the wrong direction at transition time
I believe ComputerGuru was talking about the merge into the left lane of the intersecting road while exiting the highway and turning left. It's not the most intuitive of arrangements, especially when combined with the left-hand exit following shortly. Hopefully the drivers on the intersecting road will be sufficiently surprised by the arrangement to break the usual expectation of the left lane being a through lane with higher speed.
Yeah, that situation is where I see it 2nd-most; first most is people trying to change lanes into an exit lane right at the exit when they're in a non-exit lane and want to exit. Those are lane changes, though, not merges.
It's not that straightforward. It's two adjacent lanes, which gets separated. Left one becomes an exit, the lane next to that one continues. The space between them keeps growing. The two lanes in question have a solid line between them before they separate to indicate you can't cross between them.
Maybe I didn't make it clear, people will be in the right lane and the assistant will instruct them last second to move to the left lane. This creates a dangerous situations as many US drivers do not care about traffic laws and cross the median. This is dangerous since this is generally unexpected to other drivers who will often have to sverve / brake to avoid collissions.
As someone who drives this exact stretch of road every day, in a Tesla, I agree. This lane is the end of a long stretch of road with either zero or minimal shoulder, where even the slightest glitch could cause a scrape on the side of your car. I'm always paranoid driving this stretch.
This concrete barrier is also quite a distance past where this left exit lane starts to separate from the rest of US-101, so there are really only two ways you'd risk hitting it. First, and probably most common, is people who change their minds last-second about taking that exit. Second, would be a serious AP screw-up (like what might have happened here).
FWIW, I've never had AP engaged when driving through this spot, and almost instinctively disable it when taking a highway off-ramp/change-over.
Note: Both left lanes are HOV lanes. #1 leads onto Hwy 85, #2 onto Hwy 101. Do they say which lane he was in before entering the median?
Just curious why autopilot would be in lane #1 if he intended to stay on Hwy 101. Or vice versa. Maybe it couldn't make a safe lane change sooner? (Pure speculation)
The exit for the 5 North from the 110 freeway is a left exit with a wicked left turn. This means that a) people unfamiliar with the area don't know to be in the left lane to make the exit and b) because of the sharp left turn, everyone has to slow down to <25mph and traffic backs up making the exit difficult to merge into if you're late getting into the lane. It's a bad interchange because that one lane can back up for a mile during rush hour. It's such a poorly designed exit that Caltrans recently added in lights to the lane divider in the pavement to signal that people cannot merge into that lane within about 1/4 mile of the exit during rush hour.
I've noticed while driving in the US that American highway exits seem to be designed differently than those in the UK. The rightmost lane of three-lane highways will often become the exit lane, so if you stick to the rightmost lane you'll frequently need to switch lanes to your left to stay on the road. In the UK, in contrast, the exit lane is usually the new lane, and you have to switch lanes to get into it.
So instead of constant lane switching, use the middle lane for going straight ahead, and the leftmost lane for passing.
Looks like relatively normal behavior for a 7 lane road for either USA or Europe.
Highways with THAT many lanes typically have exits on both the right and left side. People will typically be on whichever side their exit is going to be on.
It's either changing 3 lanes to the right or 1 to the left. In case of loss of control, in this case with the car coming to a stop very quickly, it might be better heading for the left lane, instead of getting stuck in the middle or second lane from the right.
in Pittsburgh, part of the reason is that there are some exit ramps off the left lane. People who are afraid to change lanes get in the left lane and stay there for miles so they don't have to merge to get to the ramp
At this interchange, I've seen lots of human drivers change between the exiting HOV lane and the continuing HOV lane (or vice versa) much later than is safe; presumably because they were surprised that their lane was exiting, or they noticed the exit too late, but didn't want to miss it. I haven't seen anyone drive in between the two lanes as if it was a lane, though; and usually the late lane changers are braking, not accelerating.
It is unfortunate that the crash attenuator wasn't reset. Looking at the docs for a similar attenuator[1], it seems like resetting is somewhat involved, and you'd need a trained and properly equipped repair crew to do it, even if the time required is not that much. Scheduling is probably an issue.
[1] https://www.dmtraffic.com/assets/sci_smart_cushion_design_an... page 9-13
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