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Elon Musk doesn't understand geometry

humantransit.org

1–10 of 34 posts

Re: Elon Musk doesn't understand geometry

#2
No, Elon does understand geometry — this author doesn’t understand the free market.

On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient.

Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massive exhaust plumes from the unnecessarily idling traffic.

Stop subsidizing sub-standard solutions, and let the transit-using public decide.

Re: Elon Musk doesn't understand geometry

#3
Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry."

The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each carrying an average of two people, the street surface area occupied by the small vehicles will be significantly greater and traffic will slow down to a crawl. Imagine a gazillion small vehicles stopping everywhere to pick up and drop off passengers. As the OP correctly points out, finding ways to use space efficiently is the core problem of urban transportation.

Re: Elon Musk doesn't understand geometry

#4

No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massi…

Alternatively, you could incentive people taking transit by making cars more expensive (by pricing in externalities).

Re: Elon Musk doesn't understand geometry

#5
post #4

No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massi…

Alternatively, you could incentive people taking transit by making cars more expensive (by pricing in externalities).

>(by pricing in externalities).

In practice, this means someone pockets the change and nothing gets done about the so called externalities.

Re: Elon Musk doesn't understand geometry

#6
post #3

Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry." The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each ca…

The additional vehicles could simply drive around the "hot" zones...

Re: Elon Musk doesn't understand geometry

#7

No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massi…

You don't ride buses much do you? Of all the times I've ridden regular bus routes, there's only been one route where the bus being 90% empty would not be extremely atypical--and even then, that was only when I was picking up the bus during off-peak hours. More frequent have been the times where there being anything other than standing room available was the atypical situation.

If you're in an urban environment at least as densely packed as, say, San Jose, then the bus system is likely to have actually quite substantial ridership. By the time you get to the kinds of dense urban environments of the standard major US cities (NYC, Chicago, DC, Philly, Boston), I quite assure that the buses are routinely packed. The story might be different if we're talking about, say, Bismarck.

Furthermore, I should point out that if a bus is stopped "pil[ing] up traffic behind them", that's because it's letting passengers embark or disembark, which is a strong signal that the bus probably isn't 90% empty.

Re: Elon Musk doesn't understand geometry

#8
If policy makers had the authors perfect understanding of geometry :

* We would be living in tiny cubicles and sharing amenities with N people (N is a function of whatever factors the authorities deem important.)

* Strapped to vertical planks for flights.

* Have perfectly circular(/spherical?) cities with poorer people commuting from farther rings.

* Work in tiny cubicles (This has already happened, thanks beancounters!).

* Children carted away to boarding schools to not disrupt routines of productive people and ensure optimal education (sounds familiar?).

* Industrial workers deployed to worksites for N months (N is a function beyond your control..)

Re: Elon Musk doesn't understand geometry

#9
post #3

Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry." The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each ca…

The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes.

Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues:

>Most mass transit systems move people in groups over scheduled routes. This has inherent inefficiencies. For passengers, time is wasted by waiting for the next vehicle to arrive, indirect routes to their destination, stopping for passengers with other destinations, and often confusing or inconsistent schedules. Slowing and accelerating large weights can undermine public transport's benefit to the environment while slowing other traffic.

>Personal rapid transit systems attempt to eliminate these wastes by moving small groups nonstop in automated vehicles on fixed tracks. Passengers can ideally board a pod immediately upon arriving at a station, and can – with a sufficiently extensive network of tracks – take relatively direct routes to their destination without stops

[1] https://en.wikipedia.org/wiki/Personal_rapid_transit

Re: Elon Musk doesn't understand geometry

#10
there are a few problems with the article: first, busses in US cities are either too full on clogged streets or too empty on empty streets to have an average load factor high enough to make them less polluting than cars. Cars. even ordinary sedans, used as shared robotaxis could readily beat busses environmentally. But once you get purpose-built mini-bus robotaxis, that will dominate in efficiency.

I'm all for better social amenities, but, in the US, with maybe a couple exceptions, robot-rides-on-demand is the likely winner, and it will be a near ideal free market: No barriers to entry, relatively low capex to get started, intermediaries enabling any size fleet to get customers, etc.

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