The Next Generation of the Interstate

[Max Rockatansky]

What happens if the 150 MPH AI car decides to pull a Blaine the Mono?

[kphoger]

I forget which thread it was, but I recall looking up the average annual salary once in Jalisco.  At the time the average income was something around 70-75K Pesos for your average Jalisco citizen.

-  Consider a basic new car costs over $200,000 Pesos.  That is just a plain luxury most cannot afford.  Older cars stay on the road pretty much as long as they will keep running.

This.  If all you do is drive down the autopista, it's easy to forget how poor of a country Mexico is.  The number of late-model SUVs zooming by you, with license plates from six states away, at 90 mph:  it certainly isn't representative of the population as a whole.  Long-distance driving is something most people cannot afford to do on more than rare occasions.

For those occasional trips, many Mexicans just take the bus.  A bus ticket from Nuevo Laredo to Monterrey costs about 700 MXN, and there are dozens of buses running every day.  Driving a car, at 25 mpg fuel economy, costs upwards of 500 MXN in gas;  if you take the toll road, the tolls are upwards of 400 MXN.

[Max Rockatansky]

I forget which thread it was, but I recall looking up the average annual salary once in Jalisco.  At the time the average income was something around 70-75K Pesos for your average Jalisco citizen.

-  Consider a basic new car costs over $200,000 Pesos.  That is just a plain luxury most cannot afford.  Older cars stay on the road pretty much as long as they will keep running.

This.  If all you do is drive down the autopista, it's easy to forget how poor of a country Mexico is.  The number of late-model SUVs zooming by you, with license plates from six states away, at 90 mph:  it certainly isn't representative of the population as a whole.  Long-distance driving is something most people cannot afford to do on more than rare occasions.

For those occasional trips, many Mexicans just take the bus.  A bus ticket from Nuevo Laredo to Monterrey costs about 700 MXN, and there are dozens of buses running every day.  Driving a car, at 25 mpg fuel economy, costs upwards of 500 MXN in gas;  if you take the toll road, the tolls are upwards of 400 MXN.

I would say though that "poor" is a relative term.  Just because life doesn't fully resemble that of the United States it doesn't mean it is the same thing as abject poverty. 

I'm amused sometimes whenever K12 or one of these so called futurists post outlandish things like the 150 MPH AI car.  It reeks as being completely divorced from how the rest of the world is.  Latin America is barely getting EVs as uber high end luxury cars for the wealthy.  I can't fathom a time in these next half century where small aging ICE sedans with manual transmissions won't be a thing on Mexican roads. 

[formulanone]

Tying this all back into the conversation about the next generation of Interstate, and kernals12's ideas about dedicated super-fast freeways for platoons of sensor-laden problem-free electric smart cars...  This sort of thing would only benefit the wealthy, those who could afford such a hugely expensive vehicle and keep up on the repairs to satisfaction.  And who would fund the project?  Taxpayers, most of whom would have no use for it?  Private investors, who would surely prefer all the toll revenue possible—which would surely include older, dumber, less well-maintained, normal vehicles?  It would be a huge waste of money, likely funded in large part by those who don't have much money to spare and would reap little to no benefit from it once it was completed.

We actually have this model in the US; it's called a racetrack: Generally privately-funded, paid for and used by those with deep pockets (or some enthusiasts). The driving populace is generally unaffected.

Most racing tracks do not make a tremendous amount of money; they're vanity projects.

[Dirt Roads]

Back to the OP's intentions:

In the early 1990s, my employer decided that we should attend the Intelligent Transportation Systems conferences, since our firm's experience with fully automated fixed guideway transit systems kinda fell in the category of ITS (which is now better known as Intelligent Vehicle Highway Systems).  After a couple of years, we decided that the ITS Committee was [literally] going down the road rather than down the technology highway.

But my take at the time was that the most promising ITS technology was in the area of congestion management.  And indeed, I witnessed the development of the Dynamic Traffic Management systems on the Rijsweg A4 in the Netherlands in 1998 and 1999 while I was working on several unrelated projects.  That system (which appears to still be working) employs variable speed limits for the purpose of slowing down mainline freeway traffic in approach to bottlenecks or short-term congestion areas.  In a nutshell, if the surge traffic can back off just a little bit, the average speeds in the bottleneck will remain significantly higher and thus result in a higher throughput (VPHPL).

After more than 25 years, this fairly simple and effective technology has yet to be considered here in the United States because Americans are not likely to adhere to the variable speed limits.

[DTComposer]

I've often wondered if there was a system like that in place somewhere - I also envisioned variable speed signs on on-ramps, telling people what speed they should be at to safely merge onto the freeway.

[kphoger]

I also envisioned variable speed signs on on-ramps, telling people what speed they should be at to safely merge onto the freeway.

Except that...

It seems that the common opinion on here holds two things about merging traffic that don't jive very well in my driving experience:

(1) Entering traffic should be at full cruising speed by the time they get on the highway; and
(2) Through traffic should not alter its speed for merging traffic, rather merging traffic should alter its speed.

Too many times, this has put me side-by-side with a vehicle (sometimes an 18-wheeler) mere yards from the end of my acceleration lane.  I, as entering traffic find it much easier to find a gap in traffic if there is at least 5 mph difference between my speed and the prevailing speed of through traffic.  Since the through traffic in question is usually in the slow lane (most on-ramps come from the right), which means it is moving at the slower end of the speed continuum, I actually find it easier to merge at 5—10 mph under the posted speed limit. [...] If I accelerate to 60 mph and traffic is moving at 60 mph, then there's a good chance I'll be neck and neck with a truck and no wiggle room. [...] Instead, I find it much easier to approach the merge at about 45 mph–still slow enough to slam on my brakes if need be, but fast enough to accelerate to 55 or 60 by the time anyone else would have to hit their brakes–or at least do anything more than tap them.

a 5-10 mph difference in speed is indeed very helpful.

if the fast lane is moving 77, and the slow lane 67, then you can merge at one of two speeds:

1) 57mph.  staid but respectable.
2) 77mph.  it is elegantly also the speed of the fast lane.

under no circumstances is merging at slower than 57mph acceptable.

[PColumbus73]

I also envisioned variable speed signs on on-ramps, telling people what speed they should be at to safely merge onto the freeway.

Except that...

It seems that the common opinion on here holds two things about merging traffic that don't jive very well in my driving experience:

(1) Entering traffic should be at full cruising speed by the time they get on the highway; and
(2) Through traffic should not alter its speed for merging traffic, rather merging traffic should alter its speed.

Too many times, this has put me side-by-side with a vehicle (sometimes an 18-wheeler) mere yards from the end of my acceleration lane.  I, as entering traffic find it much easier to find a gap in traffic if there is at least 5 mph difference between my speed and the prevailing speed of through traffic.  Since the through traffic in question is usually in the slow lane (most on-ramps come from the right), which means it is moving at the slower end of the speed continuum, I actually find it easier to merge at 5—10 mph under the posted speed limit. [...] If I accelerate to 60 mph and traffic is moving at 60 mph, then there's a good chance I'll be neck and neck with a truck and no wiggle room. [...] Instead, I find it much easier to approach the merge at about 45 mph–still slow enough to slam on my brakes if need be, but fast enough to accelerate to 55 or 60 by the time anyone else would have to hit their brakes–or at least do anything more than tap them.

a 5-10 mph difference in speed is indeed very helpful.

if the fast lane is moving 77, and the slow lane 67, then you can merge at one of two speeds:

1) 57mph.  staid but respectable.
2) 77mph.  it is elegantly also the speed of the fast lane.

under no circumstances is merging at slower than 57mph acceptable.

IMO merging requires both the thru car and the incoming car to work it out together.

Assuming I'm in the right lane and can't get over and there's a car on the on ramp, I'll watch them and adjust if I need to. Same if I'm merging on, I'll try to either match the speed limit or the flow of traffic and find a gap.

[Scott5114]

I've often wondered if there was a system like that in place somewhere

Washington state has an extensive variable speed limit system. Interstates 11 and 15 in Las Vegas also have some variable speed limit systems.

[vdeane]

I find it's easier to slide into a gap if I'm near the speed of traffic.  That said, I'm also of the "merging/changing lanes traffic shouldn't be forcing people to slow down to let them in unless there's no choice" mindset, so I'm much more willing to slide into a gap if I'm at full speed and the car behind doesn't have to do anything than if I'm going much slower and they would have to slow down because of me.  Granted, where I am there aren't usually a ton of trucks in the right lane, and even when there are, they usually drive the same speed regardless of whether the speed limit is 55 or 65, so they tend to go faster than me in the 55 zones where I merge in most often.

[kphoger]

IMO merging requires both the thru car and the incoming car to work it out together.

I've mentioned a few times on this thread (including to Crash_It) that Illinois state law even makes this explicit in its Vehicle Code.

Illinois state law puts equal responsibility on both drivers at a merge:

Vehicles

625 ILCS 5 – Illinois Vehicle Code

Article IX – Right-of-Way

Sec. 11-905 – Merging traffic – Notwithstanding the right-of-way provision in Section 11-901 of this Act, at an intersection where traffic lanes are provided for merging traffic the driver of each vehicle on the converging roadways is required to adjust his vehicular speed and lateral position so as to avoid a collision with another vehicle.

[Quillz]

I'm amused sometimes whenever K12 or one of these so called futurists post outlandish things like the 150 MPH AI car.  It reeks as being completely divorced from how the rest of the world is.  Latin America is barely getting EVs as uber high end luxury cars for the wealthy.  I can't fathom a time in these next half century where small aging ICE sedans with manual transmissions won't be a thing on Mexican roads. 

This is why I kind of scoff at people who turn up their nose at public transit. Someone wanting to build a bike lane to encourage more bike riding isn't out to ruin the world. It's not an evil plot. Encouraging people to take a bus isn't evil or wrong. Odds are if a single bike lane is making you late to work, you probably already left too late anyway. Terms like "road diet" are deliberately scary-sounding phrases designed to invoke certain attitudes towards people who can see the value in not being in a car 24/7.

Some people always like to make the claim that we are being "forced" into mass transit. Well, if we are, "they" certainly aren't doing a very good job. And what exactly is going to force me? Is someone going to put a gun to my head and kill me if I don't ride a bus? I feel people who make that argument are not generally worth debating with.

As always, you have to look beyond yourself. Just because YOU can afford a car and like to drive it, doesn't mean everyone else can. Just because I'm not being persecuted doesn't mean others aren't. A lot of people live where I live, and every single one of them has different lives and world views than me. And that's a good thing.