7 ms·

Why driverless cars may mean jams tomorrow

27 points by dishwishy 9y ago

thisisit 9y ago
This title is confusing. The actual title is more approachable - Why driverless cars may mean jams tomorrow Still I am confused by articles logic - Why would driveless car be any better than the current ownership model? The logic presented is - AIs that can pilot cars more closely together will boost road capacity. But using article's logic on people movement - it might entice people who actually don't drive due to various reason to actually buy a car. The increased number of cars might lead to the said jam. One of my controversial opinion is that going forward governments might be tempted to label ride sharing companies as basic necessities, just like internet, to try and improve transportation.
- shusson 9y ago
  > This title is confusing. The actual title is more approachable - Why driverless cars may mean jams tomorrow Agreed, I expected an article about the intricacies of the fruit preserve industry.
- flother 9y ago
  > This title is confusing The Economist is famous for using puns in its headlines, and this is a play on a well-known expression (that is itself a pun): https://en.m.wikipedia.org/wiki/Jam_tomorrow https://en.m.wikipedia.org/wiki/Jam_tomorrow
- carlmr 9y ago
  I also don't follow that argument. IMHO accidents and bad swarm behavior (people following too closely, switching lanes too often, accelerating and braking too much) lead to traffic jams. If we can get that improved our roads could take twice the cars.
  - annabellish 9y ago
    More, even. Driving into SF at rush hour is an exercise is mostly about being stationary with occasional jerks forward. You could improve that throughput a hundredfold if things could keep moving.
    - carlmr 9y ago
      Yeah, the non-accident, jerky kind of traffic is the one that automatic cars will almost eliminate completely. If we get to fully networked automatic cars we can use swarm intelligence to make them all accelerate at the same time and slowly increase the speed. Traffic is gone. And accidents I believe will also be minimized as soon as we get to full-automation. Even the less than ideal automatic Teslas seem to be faring slightly better than human drivers. Imagine how far we can get in 10-20 years. I'd guess maybe 1% the accidents we have now.
  - gryzilepek 9y ago
    You don't get the point: if you create an empty space on the roads (whatever solution you invent), people will start occupying it immediately, and you face the same problem again.
    - carlmr 9y ago
      No reason to get offensive, I do get the point, I'm just saying the point makes no sense. If we get to a fully automated future (that is without human drivers interfering), we can get to twice the occupancy which is I think more than the amount of children and seniors now driving cars that didn't before, and still have less traffic. It just runs counter to reality to think that every empty space you create is occupied immediately. After all there are less congested cities and more congested cities. Mostly because the less congested cities have a higher road/road width/road quality to commuter ratio. That's why Seattle and SF have huge issues. With the water and mountains it's impossible to get a good infrastructure to population ratio. And no, cities with better traffic don't start going on the road to occupy space just because it's there. There's always a need for people to commute paired with inadequate infrastructure. By utilising the infrastructure better, self-driving cars can basically increase one side of the fraction. Higher number of drivers will probably happen (seniors and children especially who couldn't drive before), but they also usually I doubt it's even more than 20-30%, seniors won't start commuting to jobs they don't have, children have more vacation, they're already only a smaller part of the population.
Animats 9y ago
No, the way it will work is that roads will have "surge pricing". You'll bid on road space before you leave, and don't get to leave until there's road space for you. US airport landing slots work like that now. Commercial flights don't take off for congested destinations until they've booked a landing slot. This eliminated circling the destination waiting for a landing slot.
- fragsworth 9y ago
  Or you could leave whenever you like, and there's an automated toll on every road that adjusts based on time of day and/or current traffic.
  - yorwba 9y ago
    That only works to prevent congestion if some people decide not to drive on a road when the toll is too high. In that case, why drive there in the first place if your AI car can tell you in advance how much it will cost.
- stevenwoo 9y ago
  California is/was? running a pilot program to charge car owners on miles driven instead of gas taxes. Maybe another option is additional "surge" charges to cover this as well. http://www.dot.ca.gov/road_charge/resources/index.html http://www.dot.ca.gov/road_charge/resources/index.html
- alex_duf 9y ago
  Then there's hope as it's probably cheaper to have buses full of people than individual cars
  - Cthulhu_ 9y ago
    It already is, but based on the availability and popularity of buses, it's not likely. IMO it's big employers that should push towards setting up large bus / train hubs in cities surrounding them, allowing commuters to only need to get to the bus station themselves. There's some companies that generate multiple percents of commuter traffic pretty much everywhere. They're the ones that should also do their part, by offering more efficient transportation and by opening satellite offices. There's no benefit in having 50.000 people work all in the same campus.
alanfranzoni 9y ago
This article seems to offer a somewhat limited vision. Personal, driverless cars may mean as many jams as today. What about "ride-sharing" driverless systems, where many people share the same car/minivan in an automated fashion, reducing the number of vehicles on the road and the need for parking? That would make, IMHO, the best compromise between mass transit (effective, but inflexible to people needs) and personal transit (ineffective, but flexible).
- deleted 9y ago
  [deleted]
- deleted 9y ago
  [deleted]
- chillydawg 9y ago
  Nobody really likes ride sharing, though. That's why people drive in the first place.
  - tmnvix 9y ago
    I assume one interpretation of 'ride sharing' is sharing the same pool of cars, but not the same car at the same time.
    - alanfranzoni 9y ago
      May be. But it may be that we share the same car/minivan.
    - mrweasel 9y ago
      Sure, but then you'd still need a large number of cars to handle peak hours, like 7 - 9 in the morning and 15 - 18 in the evening. You're not really freeing up the road if you're not reducing the number of cars.
  - alanfranzoni 9y ago
    Do people really dislike ride sharing more than public transport? Why? I dislike public transport when it's ineffective. It takes me about 45 minutes to get to work by walking + train, and there's about one train every hour (less often in the morning), so it's inflexible. If I go by bike, it's about 55 minutes (but then I need a shower, which can take a bit more if your company doesn't provide the right facilities). I'd say that the time saving for a train is ridiculous if we factor in the price for the railway system. If I go by car it's 25 minutes, but then I need to find a parking spot, and usually pay for it. If I could rideshare to work and just be dropped in front of my office, and forget about it, with a price on par (even slightly higher) than my car ride, I'd pick that solution most of the times (I'd still ride my bike for training that's it).
ImaCake 9y ago
I'm not impressed with all the crap popping up in my browser when I load this page. The economist used to be pretty good for focusing on the actual content.
- progval 9y ago
  The site works nicely with an adblocker or with NoScript
wannadub2 9y ago
CrashFunction.com
softgrow 9y ago
Driverless cars will bring safer roads in terms of exposure measures like deaths/injuries per 1 Million/km. They will also lower the monetary cost of transporting a person per km due to reduction in fleet size and optimised driving and resource allocation. This will benefit nations and economies in providing more economic growth, employment etc by moving more people and goods over the same road network and a smaller fleet. However they won't solve the fundamental problem of roads being a scarce resource that lack a price signal so the demand is infinite. If you set the price too low you get congestion. If hamburgers were free, everyone would want one and a queue will develop, so instead of paying money you pay with time. It's just the same as "free" parking where you pay time instead of money. Obligatory mention of Donald Shoup and "The High Price of Free Parking".
- ams6110 9y ago
  That's not exactly what "free" means in an economic context, but probably doesn't alter your point. Something is "free" if, at a price of zero, there is enough supply to meet demand.
  - dmichulke 9y ago
    Interesting definition. It follows that nothing is universally free, it can only be free within spatial (and probably temporal) constraints. The usual candidates (water, air) are certainly not free everywhere.
- Cthulhu_ 9y ago
  You say reduction in fleet size and whatnot, but I believe that's assuming population remains the same; as it stands, it grows with about 1% per year. That fleet size reduction would need to exceed 1% a year; I don't think that's very likely. It also implies people are willing to move from owning a car to time sharing a car. That's not likely, because it'll be businesses that will offer it, and they need to make a profit. As it stands, Uber is more expensive than taxis (and they undercut taxis using dank investment monies); take away the driver and replace it with a more expensive car, and I don't think they'd be able to operate cheaper. Plus, traffic comes in peaks, so that fleet would have to be optimized to handle said peaks. And of course, a large percentage will need (and want) to use it. It's possible if the transport system becomes government owned or it becomes competitive with car ownership, but I don't see that happening. Sci-fi utopias usually don't explain why everything is going as smoothly as it seems; one explanation is that companies are just that awesome and managed to get a cooperative traffic system up and running whilst making automagic cars cheap enough for everyone, another is that the government or some other singular but benevolent organization is in control of all transport and is making sure it's standardized.
Theodores 9y ago
Currently only a minority of people aged between 9 and 99 drive a car. Although almost every baby boomer drives it is not so for other generations. With driverless cars that you can just hop in 'taxi style' or own outright then there are going to be a lot more people taking a lot more journeys. However, the self driving car solves many other problems. For instance, in some of our cities most of the traffic is people driving around looking for some place to park. That is it, that is what they are doing rather than going somewhere important. At some stage the existing dumb cars we have parked on our streets now will get sent off to the recycling facility, if, at the same time, more people are getting glorified driverless cabs and not buying their own cars, then there really can be a sizeable bit of highway real estate to recover. Hopefully because the self driving cars go in convoy this extra road space can be for people, e.g. on bicycles, and not for yet more automobile infrastructure. Then there is the school run, no need for the journey there and back, plus the ride sharing can get smarter to know who needs to be where and when, i.e. self aware of all the meetings in town.
tomohawk 9y ago
The odds are that self driving cars will stick to the posted speed limit, and that those limits will not be raised. This will reduce the available capacity of many interstate grade roads, as the posted speed is often unsafely low. On the roads around here, the accepted and safe speed is often around 70mph, but the posted speed is often 55mph. https://www.motorists.org/blog/speed-limits-slower-safer/ https://www.motorists.org/blog/speed-limits-slower-safer/ Additionally, self driving cars appear to have a higher accident rate per mile driven (5x). This appears to be at least partly the result of the self driving cars performing unorthodox maneuvers in some situations.
- nimbix 9y ago
  This complete disregard for speed limits was a huge shock to me when I was driving in Florida 2 weeks ago. In quite a few EU countries we stick to the posted limits quite strictly. But in the US I was literally bullied into driving way above the limit (75 in a 55 zone) and was still getting overtaken on both sides - in one case even by a police car - and some people used turning lanes to overtake on the right. In addition to this everyone was slamming their brakes when they saw an empty police car parked by the side of the road. Crazy.
- DarqWebster 9y ago
  Slower not meaning safer is because a slower driver among faster drivers causes more lane-changes, which are a less-safe maneuver. Everyone travelling the same speed is the safest scenario, with slower then being safer, as impacts occur with less energy. If everyone strictly obeyed the posted speed limit and treated it as both a minimum and a maximum speed, as driverless cars would likely aim to do, roads would be safer. The interim state of having both driverless and human-driven cars on the road at the same time is where problems may arise.
douglaswlance 9y ago
Jams are caused by human drivers whose slow reaction time causes waves of slowdowns that build up into complete stoppage. We can get AI reaction time down to the speed of light since all vehicles can communicate their speed, direction, and location simultaneously. It is a totally new epoch of transportation and the old rules no longer apply.
moneytide1 9y ago
Driverless is great for quicker reaction times, but they cannot anticipate larger-scale situations. Perhaps if all cars were autonomous and connected it could work, but that will not happen for a very long time. When I see a heavy truck merge a mile ahead on the interstate, I will go ahead and get in the left lane. Heavy trucks cannot accelerate like a passenger car. If I can detect the age of the driver in front of me, I can anticipate an older person with slower response time and tendency to drive slow, so I accommodate them. In a traffic jam, I will leave 50'-100' buffer zone between me and bumper of car in front. Unfortunately, some drivers will quickly pass me and take up this zone, because people like the idea of "getting ahead". This only clogs visibility and increases braking. There are certain situations where this is not appropriate, because that buffer zone can mean other drivers getting caught at red lights. There are some tight situations where it is ideal to drive bumper-to-bumper. Interstate jams are ideal for the buffer. If the light turns red and I can see it a mile away going 55mph, I will begin my coast with minimal braking so as to conserve momentum. Most times I never get below 30 and can always catch green lights this way. I feel even better if people stay behind me while I do this, because I am essentially saving their energy by setting our pace. Sometimes slower is faster. I'd like to think that just a handful of mindful drivers in a jam can improve traffic flow.
- catbird 9y ago
  I don't see any reason why an autonomous car couldn't be trained to move to the left lane before an on ramp, or classify neighboring cars by their observed behaviors (slow reaction time, etc). Also, I would argue that maintaining a buffer zone in heavy traffic, though it may feel like you are breaking less/going faster, is not actually helpful. The flow rate of a section of highway (cars/hour) is the product of speed (miles per hour) and density (cars/mile). Leaving a space in front of you lowers the density, decreasing overall throughput. Ideally with self driving cars we could have them going at high speeds very close together (or even mechanically coupled like a train).
  - moneytide1 9y ago
    Yes, the train example would be the optimal way to use autonomy. The idea of the buffer is rooted more in energy efficiency, rather than increasing flow rate. But I understand that time may be more valuable than energy in this situation, since we are talking about the throughput of economic components (worker and resource transport). The idea is that if the buffer were used more frequently, then the average speed could increase. Multiplied by a lower density number, it could potentially be a higher flow rate. It requires more energy and time to move from a complete stop than it does to increase speed while already moving. The buffer could eliminate jams completely, if we define "jam" as standstill traffic. Merging would be smoother because there wouldn't be stop and go. Think of all the thousands of people in a 5 mile jam stretch that slow to a halt and wave their hand while the other person takes time to look at them and make sure they really do have clearance. Every time that happens, dozens of cars behind must also come to a complete halt. With the buffer, speeds may temporarily slow but never halt when introducing new vehicles into the line. If the buffer was a standard implemented in drivers ed, then all drivers would have a protocol for jams.
kthejoker2 9y ago
Anyone who commutes in a large city quickly comes to recognize when there has been either a major accident or a higher incident of minor accidents that day. Potentially even hours before, but the ramifications are right there in front of your bumper. And conversely there are days when the stars seem to align and your commute is unusually short and free of significant time going 0-5 mph. Sure you still crawl, but by comparison it feels great. Again, this is almost entirely an artifact of human-caused preventable road accidents. I fail to see how, if you accept the premise that driverless cars will dramatically reduce or outright eliminate accidents, traffic will not be permanently improved.
supreme_sublime 9y ago
Kind of tangential to this article, but I can't believe that people are willing to own a car that is impossible for them to control. While I don't think it is necessary for self driving cars to lack the option for human control, the prototypes I've seen lacked a steering wheel. Personally, I will never buy a vehicle that I cannot control if there is an option not to. Of course if the market becomes dominated by self driving cars without steering wheels, I suppose I'll have no choice. I also see a lot of talk (in other threads) about the eventual banning of drivers in favor of a totally automated driving world. Can no one see the potential problems with this? Even eliminating the potential for government control, what kind of perverse incentives might arrive for companies? Taking you on routes with more stores as a form of advertising is something I can think of just off the top of my head. Not to mention all of that kind of talk is very city-centric. Some people do have legitimate need to go places that don't have roads, or at least mapped roads. Rural places still exist, and it annoys me to see how no one seems to think about these places when talking about driverless vehicles, or banning drivers.

27 points by dishwishy 9y ago

This title is confusing. The actual title is more approachable - Why driverless cars may mean jams tomorrow Still I am confused by articles logic - Why would driveless car be any better than the current ownership model? The logic presented is - AIs that can pilot cars more closely together will boost road capacity. But using article's logic on people movement - it might entice people who actually don't drive due to various reason to actually buy a car. The increased number of cars might lead to the said jam. One of my controversial opinion is that going forward governments might be tempted to label ride sharing companies as basic necessities, just like internet, to try and improve transportation.

shusson 9y ago
> This title is confusing. The actual title is more approachable - Why driverless cars may mean jams tomorrow Agreed, I expected an article about the intricacies of the fruit preserve industry.
flother 9y ago
> This title is confusing The Economist is famous for using puns in its headlines, and this is a play on a well-known expression (that is itself a pun): https://en.m.wikipedia.org/wiki/Jam_tomorrow https://en.m.wikipedia.org/wiki/Jam_tomorrow
carlmr 9y ago
I also don't follow that argument. IMHO accidents and bad swarm behavior (people following too closely, switching lanes too often, accelerating and braking too much) lead to traffic jams. If we can get that improved our roads could take twice the cars.
- annabellish 9y ago
  More, even. Driving into SF at rush hour is an exercise is mostly about being stationary with occasional jerks forward. You could improve that throughput a hundredfold if things could keep moving.
  - carlmr 9y ago
    Yeah, the non-accident, jerky kind of traffic is the one that automatic cars will almost eliminate completely. If we get to fully networked automatic cars we can use swarm intelligence to make them all accelerate at the same time and slowly increase the speed. Traffic is gone. And accidents I believe will also be minimized as soon as we get to full-automation. Even the less than ideal automatic Teslas seem to be faring slightly better than human drivers. Imagine how far we can get in 10-20 years. I'd guess maybe 1% the accidents we have now.
- gryzilepek 9y ago
  You don't get the point: if you create an empty space on the roads (whatever solution you invent), people will start occupying it immediately, and you face the same problem again.
  - carlmr 9y ago
    No reason to get offensive, I do get the point, I'm just saying the point makes no sense. If we get to a fully automated future (that is without human drivers interfering), we can get to twice the occupancy which is I think more than the amount of children and seniors now driving cars that didn't before, and still have less traffic. It just runs counter to reality to think that every empty space you create is occupied immediately. After all there are less congested cities and more congested cities. Mostly because the less congested cities have a higher road/road width/road quality to commuter ratio. That's why Seattle and SF have huge issues. With the water and mountains it's impossible to get a good infrastructure to population ratio. And no, cities with better traffic don't start going on the road to occupy space just because it's there. There's always a need for people to commute paired with inadequate infrastructure. By utilising the infrastructure better, self-driving cars can basically increase one side of the fraction. Higher number of drivers will probably happen (seniors and children especially who couldn't drive before), but they also usually I doubt it's even more than 20-30%, seniors won't start commuting to jobs they don't have, children have more vacation, they're already only a smaller part of the population.

Animats 9y ago

No, the way it will work is that roads will have "surge pricing". You'll bid on road space before you leave, and don't get to leave until there's road space for you. US airport landing slots work like that now. Commercial flights don't take off for congested destinations until they've booked a landing slot. This eliminated circling the destination waiting for a landing slot.

fragsworth 9y ago
Or you could leave whenever you like, and there's an automated toll on every road that adjusts based on time of day and/or current traffic.
- yorwba 9y ago
  That only works to prevent congestion if some people decide not to drive on a road when the toll is too high. In that case, why drive there in the first place if your AI car can tell you in advance how much it will cost.
stevenwoo 9y ago
California is/was? running a pilot program to charge car owners on miles driven instead of gas taxes. Maybe another option is additional "surge" charges to cover this as well. http://www.dot.ca.gov/road_charge/resources/index.html http://www.dot.ca.gov/road_charge/resources/index.html
alex_duf 9y ago
Then there's hope as it's probably cheaper to have buses full of people than individual cars
- Cthulhu_ 9y ago
  It already is, but based on the availability and popularity of buses, it's not likely. IMO it's big employers that should push towards setting up large bus / train hubs in cities surrounding them, allowing commuters to only need to get to the bus station themselves. There's some companies that generate multiple percents of commuter traffic pretty much everywhere. They're the ones that should also do their part, by offering more efficient transportation and by opening satellite offices. There's no benefit in having 50.000 people work all in the same campus.

alanfranzoni 9y ago

This article seems to offer a somewhat limited vision. Personal, driverless cars may mean as many jams as today. What about "ride-sharing" driverless systems, where many people share the same car/minivan in an automated fashion, reducing the number of vehicles on the road and the need for parking? That would make, IMHO, the best compromise between mass transit (effective, but inflexible to people needs) and personal transit (ineffective, but flexible).

deleted 9y ago
[deleted]
deleted 9y ago
[deleted]
chillydawg 9y ago
Nobody really likes ride sharing, though. That's why people drive in the first place.
- tmnvix 9y ago
  I assume one interpretation of 'ride sharing' is sharing the same pool of cars, but not the same car at the same time.
  - alanfranzoni 9y ago
    May be. But it may be that we share the same car/minivan.
  - mrweasel 9y ago
    Sure, but then you'd still need a large number of cars to handle peak hours, like 7 - 9 in the morning and 15 - 18 in the evening. You're not really freeing up the road if you're not reducing the number of cars.
- alanfranzoni 9y ago
  Do people really dislike ride sharing more than public transport? Why? I dislike public transport when it's ineffective. It takes me about 45 minutes to get to work by walking + train, and there's about one train every hour (less often in the morning), so it's inflexible. If I go by bike, it's about 55 minutes (but then I need a shower, which can take a bit more if your company doesn't provide the right facilities). I'd say that the time saving for a train is ridiculous if we factor in the price for the railway system. If I go by car it's 25 minutes, but then I need to find a parking spot, and usually pay for it. If I could rideshare to work and just be dropped in front of my office, and forget about it, with a price on par (even slightly higher) than my car ride, I'd pick that solution most of the times (I'd still ride my bike for training that's it).

ImaCake 9y ago

I'm not impressed with all the crap popping up in my browser when I load this page. The economist used to be pretty good for focusing on the actual content.

progval 9y ago
The site works nicely with an adblocker or with NoScript

wannadub2 9y ago

CrashFunction.com

softgrow 9y ago

Driverless cars will bring safer roads in terms of exposure measures like deaths/injuries per 1 Million/km. They will also lower the monetary cost of transporting a person per km due to reduction in fleet size and optimised driving and resource allocation. This will benefit nations and economies in providing more economic growth, employment etc by moving more people and goods over the same road network and a smaller fleet. However they won't solve the fundamental problem of roads being a scarce resource that lack a price signal so the demand is infinite. If you set the price too low you get congestion. If hamburgers were free, everyone would want one and a queue will develop, so instead of paying money you pay with time. It's just the same as "free" parking where you pay time instead of money. Obligatory mention of Donald Shoup and "The High Price of Free Parking".

ams6110 9y ago
That's not exactly what "free" means in an economic context, but probably doesn't alter your point. Something is "free" if, at a price of zero, there is enough supply to meet demand.
- dmichulke 9y ago
  Interesting definition. It follows that nothing is universally free, it can only be free within spatial (and probably temporal) constraints. The usual candidates (water, air) are certainly not free everywhere.
Cthulhu_ 9y ago
You say reduction in fleet size and whatnot, but I believe that's assuming population remains the same; as it stands, it grows with about 1% per year. That fleet size reduction would need to exceed 1% a year; I don't think that's very likely. It also implies people are willing to move from owning a car to time sharing a car. That's not likely, because it'll be businesses that will offer it, and they need to make a profit. As it stands, Uber is more expensive than taxis (and they undercut taxis using dank investment monies); take away the driver and replace it with a more expensive car, and I don't think they'd be able to operate cheaper. Plus, traffic comes in peaks, so that fleet would have to be optimized to handle said peaks. And of course, a large percentage will need (and want) to use it. It's possible if the transport system becomes government owned or it becomes competitive with car ownership, but I don't see that happening. Sci-fi utopias usually don't explain why everything is going as smoothly as it seems; one explanation is that companies are just that awesome and managed to get a cooperative traffic system up and running whilst making automagic cars cheap enough for everyone, another is that the government or some other singular but benevolent organization is in control of all transport and is making sure it's standardized.

Theodores 9y ago

Currently only a minority of people aged between 9 and 99 drive a car. Although almost every baby boomer drives it is not so for other generations. With driverless cars that you can just hop in 'taxi style' or own outright then there are going to be a lot more people taking a lot more journeys. However, the self driving car solves many other problems. For instance, in some of our cities most of the traffic is people driving around looking for some place to park. That is it, that is what they are doing rather than going somewhere important. At some stage the existing dumb cars we have parked on our streets now will get sent off to the recycling facility, if, at the same time, more people are getting glorified driverless cabs and not buying their own cars, then there really can be a sizeable bit of highway real estate to recover. Hopefully because the self driving cars go in convoy this extra road space can be for people, e.g. on bicycles, and not for yet more automobile infrastructure. Then there is the school run, no need for the journey there and back, plus the ride sharing can get smarter to know who needs to be where and when, i.e. self aware of all the meetings in town.

tomohawk 9y ago

The odds are that self driving cars will stick to the posted speed limit, and that those limits will not be raised. This will reduce the available capacity of many interstate grade roads, as the posted speed is often unsafely low. On the roads around here, the accepted and safe speed is often around 70mph, but the posted speed is often 55mph. https://www.motorists.org/blog/speed-limits-slower-safer/ https://www.motorists.org/blog/speed-limits-slower-safer/ Additionally, self driving cars appear to have a higher accident rate per mile driven (5x). This appears to be at least partly the result of the self driving cars performing unorthodox maneuvers in some situations.

nimbix 9y ago
This complete disregard for speed limits was a huge shock to me when I was driving in Florida 2 weeks ago. In quite a few EU countries we stick to the posted limits quite strictly. But in the US I was literally bullied into driving way above the limit (75 in a 55 zone) and was still getting overtaken on both sides - in one case even by a police car - and some people used turning lanes to overtake on the right. In addition to this everyone was slamming their brakes when they saw an empty police car parked by the side of the road. Crazy.
DarqWebster 9y ago
Slower not meaning safer is because a slower driver among faster drivers causes more lane-changes, which are a less-safe maneuver. Everyone travelling the same speed is the safest scenario, with slower then being safer, as impacts occur with less energy. If everyone strictly obeyed the posted speed limit and treated it as both a minimum and a maximum speed, as driverless cars would likely aim to do, roads would be safer. The interim state of having both driverless and human-driven cars on the road at the same time is where problems may arise.

douglaswlance 9y ago

Jams are caused by human drivers whose slow reaction time causes waves of slowdowns that build up into complete stoppage. We can get AI reaction time down to the speed of light since all vehicles can communicate their speed, direction, and location simultaneously. It is a totally new epoch of transportation and the old rules no longer apply.

moneytide1 9y ago

Driverless is great for quicker reaction times, but they cannot anticipate larger-scale situations. Perhaps if all cars were autonomous and connected it could work, but that will not happen for a very long time. When I see a heavy truck merge a mile ahead on the interstate, I will go ahead and get in the left lane. Heavy trucks cannot accelerate like a passenger car. If I can detect the age of the driver in front of me, I can anticipate an older person with slower response time and tendency to drive slow, so I accommodate them. In a traffic jam, I will leave 50'-100' buffer zone between me and bumper of car in front. Unfortunately, some drivers will quickly pass me and take up this zone, because people like the idea of "getting ahead". This only clogs visibility and increases braking. There are certain situations where this is not appropriate, because that buffer zone can mean other drivers getting caught at red lights. There are some tight situations where it is ideal to drive bumper-to-bumper. Interstate jams are ideal for the buffer. If the light turns red and I can see it a mile away going 55mph, I will begin my coast with minimal braking so as to conserve momentum. Most times I never get below 30 and can always catch green lights this way. I feel even better if people stay behind me while I do this, because I am essentially saving their energy by setting our pace. Sometimes slower is faster. I'd like to think that just a handful of mindful drivers in a jam can improve traffic flow.

catbird 9y ago
I don't see any reason why an autonomous car couldn't be trained to move to the left lane before an on ramp, or classify neighboring cars by their observed behaviors (slow reaction time, etc). Also, I would argue that maintaining a buffer zone in heavy traffic, though it may feel like you are breaking less/going faster, is not actually helpful. The flow rate of a section of highway (cars/hour) is the product of speed (miles per hour) and density (cars/mile). Leaving a space in front of you lowers the density, decreasing overall throughput. Ideally with self driving cars we could have them going at high speeds very close together (or even mechanically coupled like a train).
- moneytide1 9y ago
  Yes, the train example would be the optimal way to use autonomy. The idea of the buffer is rooted more in energy efficiency, rather than increasing flow rate. But I understand that time may be more valuable than energy in this situation, since we are talking about the throughput of economic components (worker and resource transport). The idea is that if the buffer were used more frequently, then the average speed could increase. Multiplied by a lower density number, it could potentially be a higher flow rate. It requires more energy and time to move from a complete stop than it does to increase speed while already moving. The buffer could eliminate jams completely, if we define "jam" as standstill traffic. Merging would be smoother because there wouldn't be stop and go. Think of all the thousands of people in a 5 mile jam stretch that slow to a halt and wave their hand while the other person takes time to look at them and make sure they really do have clearance. Every time that happens, dozens of cars behind must also come to a complete halt. With the buffer, speeds may temporarily slow but never halt when introducing new vehicles into the line. If the buffer was a standard implemented in drivers ed, then all drivers would have a protocol for jams.

kthejoker2 9y ago

Anyone who commutes in a large city quickly comes to recognize when there has been either a major accident or a higher incident of minor accidents that day. Potentially even hours before, but the ramifications are right there in front of your bumper. And conversely there are days when the stars seem to align and your commute is unusually short and free of significant time going 0-5 mph. Sure you still crawl, but by comparison it feels great. Again, this is almost entirely an artifact of human-caused preventable road accidents. I fail to see how, if you accept the premise that driverless cars will dramatically reduce or outright eliminate accidents, traffic will not be permanently improved.

supreme_sublime 9y ago

Kind of tangential to this article, but I can't believe that people are willing to own a car that is impossible for them to control. While I don't think it is necessary for self driving cars to lack the option for human control, the prototypes I've seen lacked a steering wheel. Personally, I will never buy a vehicle that I cannot control if there is an option not to. Of course if the market becomes dominated by self driving cars without steering wheels, I suppose I'll have no choice. I also see a lot of talk (in other threads) about the eventual banning of drivers in favor of a totally automated driving world. Can no one see the potential problems with this? Even eliminating the potential for government control, what kind of perverse incentives might arrive for companies? Taking you on routes with more stores as a form of advertising is something I can think of just off the top of my head. Not to mention all of that kind of talk is very city-centric. Some people do have legitimate need to go places that don't have roads, or at least mapped roads. Rural places still exist, and it annoys me to see how no one seems to think about these places when talking about driverless vehicles, or banning drivers.