151–160 of 217 posts
Earlier quoted context omitted.
Then add more trains until you don't need to look at a schedule anymore (every fifteen minutes at the absolute worst). EDIT: Punctuation
Standing for 14 minutes in the cold pissing rain is not fun. And that still doesn't solve the problem of getting to and from the train station.
Earlier quoted context omitted.
Those won't go away. They might be mitigated, but once again, you can only mitigate the portion that is due to driver error, and the major problem in those scenarios is physics. The shock wave phenomenon is one caused by physics (it literally is modeled by fluid dynamics simulation), exacerbated by limited visibility, and exacerbated once again by human reaction times. You can only get rid of the human reaction times…
Those traffic waves are in large part psychology though. If every car traveled at the average speed you wouldn't have them. If even just 10% are self driving and have data on average speed for that section of road, they can not only avoid the wave but break them up, making traffic better for everyone. I've even done this myself. I see a standing wave in front of me and slow to what I know is about average for that ti…
We know, due to fluid dynamics simulation, that reduced reaction times will make traffic more resilient to small fluctuations in speed (they can "recover" from the shock wave with lower space requirements), but when the freeway is at capacity there is no recovery room and the shock wave will happen regardless of reaction time.
Earlier quoted context omitted.
Well, since I put significant work into doing napkin calculations on this and would like to get some mileage on it, here's my comment from a discussion yesterday ( https://news.ycombinator.com/item?id=13172888 ). Edit: It should be noted this was in the context of a discussion regarding ad-hoc pairing systems for carpooling/ride-sharing possibly making car travel much more efficient, possibly with vehicles that seat…
Replying to this one as I don't want to reply to yesterday's thread. (numbers unrelated to yours) 1. BART track utilization at peak times is already pretty much at capacity. The typical westbound rush hour train will be waiting in the transbay tube for trains ahead of it to unload passengers at Embarcadero. 2. Seating capacity on BART is underreporting the ridership. At least 30 more people fit into each car during p…
I was hoping people would chime in with actual experiences. I've lived an hour North of SF all my life, but have never ridden BART. There's little reason to if you already have to drive quite a distance just to get to a station, and you only visit the city occasionally.
> Seating capacity on BART is underreporting the ridership. At least 30 more people fit into each car during peak and late hours.
30 more people from the per-car numbers, or from the "crush" load they report, which is "over 200" (and I used 200 for my calculations).
> I don't see how the city could accommodate the extra usage from the loss of BART, van/bus use notwithstanding.
I wasn't really making a case for eliminating BART, but more for where future load capacity might come from. If we already have a mass transit system the numbers show it's a very efficient, if fairly rigid solution than we should keep that and expand it as much as feasible (which likely means, maximizing current tracks, not creating new ones).
That said, a lane packed with buses is much more dense with people than even BART, so dedicated bus lanes (10+ seat vehicles) combined with a shift to ad-hoc ride sharing might do it. Getting from here to there would be hard though.
Bit of a conspiracy theory sort of question, but... is there any reason to believe that maybe self-driving car technology is being backed by the military-industrial complex as a way to run R&D for military automation and related technologies? That could explain why there was a sudden spike in interest in this technology several years ago, and it could also explain why enormous amounts of hype are continually being ge…
There's no conspiracy about it - that is exactly what happened, and it happened right out in the open, in the form of the DARPA Grand Challenge races in 2004-2007. The explicitly stated goal of those races was to motivate research into autonomous vehicles that would enable the US military to begin converting its ground vehicles to autonomous operation. The much-hyped commercial applications are a spin-off.
Google/Waymo and its successors are using pre-mapped courses with many heuristics and edge case tweaks. Routes are generated from existing resources (Google Maps, etc). Much effort is devoted to avoiding other vehicles and pedestrians. Much of the rules are based off of U.S. traffic rules, such as speed limits, stop signs, traffic signals, and lane markings.
They both share technology (computer vision, momentum/traction control), but I conjecture the bulk of the work for commercial autonomous driving was not related to the DARPA challenge and wasn't paid by its grants.
Bit of a conspiracy theory sort of question, but... is there any reason to believe that maybe self-driving car technology is being backed by the military-industrial complex as a way to run R&D for military automation and related technologies? That could explain why there was a sudden spike in interest in this technology several years ago, and it could also explain why enormous amounts of hype are continually being ge…
Very weak conspiracy theory. A better one is that the private sector lags military technology by at least 50 years.
Earlier quoted context omitted.
Replying to this one as I don't want to reply to yesterday's thread. (numbers unrelated to yours) 1. BART track utilization at peak times is already pretty much at capacity. The typical westbound rush hour train will be waiting in the transbay tube for trains ahead of it to unload passengers at Embarcadero. 2. Seating capacity on BART is underreporting the ridership. At least 30 more people fit into each car during p…
> BART track utilization at peak times is already pretty much at capacity. The typical westbound rush hour train will be waiting in the transbay tube for trains ahead of it to unload passengers at Embarcadero. I was hoping people would chime in with actual experiences. I've lived an hour North of SF all my life, but have never ridden BART. There's little reason to if you already have to drive quite a distance just to…
I would love to see a bus-only lane. I wish Market St was closed to normal passenger traffic and only for busses and delivery/maintenance vehicles.
Earlier quoted context omitted.
People in urban environments, maybe. Never going to be the case for the majority of areas.
Yes, just the >80% of the population in urban centres (developed countries), >50% worldwide and increasing rapidly. Tiny market!
Regardless, Uber et. al. doesn't reach where I live. It's not an option. It's not a choice at the moment. Living in an urban area doesn't mean you are living in the city. Public transportation is a long way off from being viable out here in these urban areas.
Right now, you cannot live and work here without having a car (unless you limit yourself to very specific conditions, but that could be said for all locations). And again, this is considered to be an urban county.
Earlier quoted context omitted.
Those traffic waves are in large part psychology though. If every car traveled at the average speed you wouldn't have them. If even just 10% are self driving and have data on average speed for that section of road, they can not only avoid the wave but break them up, making traffic better for everyone. I've even done this myself. I see a standing wave in front of me and slow to what I know is about average for that ti…
I'm not convinced, and I don't think there is very much evidence either way. Are the traffic waves caused by erratic driving due to driver error at misjudging average speed? Or is it more caused by small fluctuations due to actual and unavoidable conditions? Would a self driving car see a plastic bag blowing in the wind and slam on its brakes, or drive right through it? What about a kitten? What about a bowling ball,…
Earlier quoted context omitted.
There's no conspiracy about it - that is exactly what happened, and it happened right out in the open, in the form of the DARPA Grand Challenge races in 2004-2007. The explicitly stated goal of those races was to motivate research into autonomous vehicles that would enable the US military to begin converting its ground vehicles to autonomous operation. The much-hyped commercial applications are a spin-off.
The DARPA challenge is somewhat of an orthogonal use case. The DARPA challenge was based off of an autonomous vehicle that doesn't have extensively pre-mapped roads; it is in rough terrain. The vehicle had to alter its route on-the-fly if it encountered impassable obstacles. It also didn't have to concern itself with traffic. I presume the use case is getting materiel to troops without risking human drivers. This is…
Sure, of course you're right that "the bulk of the work" is not related. But it's also no secret that the "sudden spike in interest in this technology" lucker referred to above happened because the US government paid for it to happen, as a means of advancing military vehicle automation technology.
Earlier quoted context omitted.
The problem with this is, as a rider, I personally would not want to have to be constantly expecting a dirty car. If one out of every 3 cars has vomit or syringes in it or feces, I would personally stick with a service that has human drivers at the wheel.
This is remedied with a service charge for the responsible person. Unlike a Tenderloin sidewalk, deterrents are easily enforced under a scheme like this. Uber and Lyft currently charge $100 for a cleaning fee to the driver when their passengers soil a car's interior with vomit, etc. I don't see why Waymo, Tesla, or Uber would be any different.