10 ms·

DeepTraffic is a gamified simulation of typical highway traffic

180 points by kiril-me 10y ago

raverbashing 10y ago
8 lanes is easy Try driving in 2 lanes with random people switching lanes in front of you, people randomly blocking your lane to turn, etc, also make sure you get into your destination on time
jstanley 10y ago
Why is everybody driving in random lanes? You should only go into the outer lanes to overtake traffic, and then move back in once you've passed. It's not just the law, it's a good idea... EDIT: And for anyone looking for more info, this seems to be a more useful page: http://selfdrivingcars.mit.edu/deeptraffic/ http://selfdrivingcars.mit.edu/deeptraffic/
- fatuna 10y ago
  As far as I know, it is common in Europe to only overtake on the outer lanes. In the US however, there are no such rules. It does seem like a good idea to me.
  - splike 10y ago
    The law exists in the US, but nobody bothers to follow it from my experience driving there. People just seem to use the other lanes as more road.
    - nrjdhsbsid 10y ago
      It's pretty well followed on the highway in low traffic conditions. Trucks and such will stay right. During heavy traffic nobody gives a flying fuck though, and I've never heard of the law being enforced once if it wasn't a charge being tacked onto something else like reckless driving
      - 6DM 10y ago
        On top of that, there will always be "sections" of the road where traffic reliably grinds to a halt. So people keep switching back and forth to avoid those areas.
    - seanmcdirmid 10y ago
      The US does not have one set of traffic laws for all states.
      - maxerickson 10y ago
        Most states follow the Uniform Vehicle Code on this issue http://jalopnik.com/5501615/left-lane-passing-laws-a-state-by-state-map http://jalopnik.com/5501615/left-lane-passing-laws-a-state-b... (and among those that don't 1/2 of them still have laws about obstructing traffic)
        dsp1234 10y ago
        The issue mentioned in your linked article is different from what's mentioned up thread. The article deals with "what is the role of the very left lane". Upthread it's about using non-outer lanes (inner lanes) as the passing lane, which implies passing on the right. The UVC specifically allows passing on the right on a paved road with 2, or more, lanes (see 11-304(a)(2))
        maxerickson 10y ago
        jstanley at the top of the thread is clearly talking about the same thing as my article, keeping right except when passing. You should only go into the outer lanes to overtake traffic, and then move back in once you've passed. It's not just the law, it's a good idea... That's not about passing on the right.
        dsp1234 10y ago
        The outer lanes are the left and right lanes. Which implies that, given 3 lanes, someone is passing on the right. At a base level, given more than 2 lanes, there is a difference between "stay out of the left lane unless passing", and "stay out of the left and right lanes unless passing", as it gives drivers twice as many options for passing.
        10y ago
    - virgil_disgr4ce 10y ago
      What I've never understood about this idea is that it suggests that speeding must not be illegal in that passing lane. But that's not true. So then how does a law for a passing lane work?
      - mulmen 10y ago
        I'm not sure where you get the suggestion that there is no speed limit in the passing lane. We drive on the right so the safest place to pass is on the left where the driver is. If everyone stays right as much as possible and faster traffic (this does not imply speeding) can move left to pass then traffic flows smoothly. Where are you getting the impression that speeding is allowed anywhere?
        nkurz 10y ago
        > Where are you getting the impression that speeding is allowed anywhere? One reason is that in many places in the US, the normal traffic speed exceeds the legal posted limit by 5-15 miles per hour. If the law requires a driver travelling at the legal speed limit to stay out of the "passing lane" so that other drivers can pass, this would imply that the law condones speeding, since only a driver moving faster than the legal speed limit can make use of that lane. If the law was not intended to encourage exceeding the speed limit, it likely would have been written as something like "any driver moving less the legal speed limit must avoid the passing lane". Another reason is that some US states make exceptions to the normal speed limit when passing another vehicle on a two lane road: http://blog.seattlepi.com/seattle911/2014/10/10/can-i-speed-while-passing/ http://blog.seattlepi.com/seattle911/2014/10/10/can-i-speed-..., http://www.mlive.com/news/index.ssf/2012/03/traffic_talk_comments_should_t_1.html http://www.mlive.com/news/index.ssf/2012/03/traffic_talk_com.... While one could argue that it's not "speeding" if it's not illegal, it's not unreasonable to interpret such laws as "allowing speeding" to pass.
        mulmen 10y ago
        > If the law requires a driver travelling at the legal speed limit to stay out of the "passing lane" so that other drivers can pass, this would imply that the law condones speeding, since only a driver moving faster than the legal speed limit can make use of that lane. That's not how it works. The law is "stay right except to pass". This is true regardless of speed. Speeding is still illegal in any lane. The "stay right" rule is about not obstructing the flow of traffic, it has nothing to do with the posted speed limit. e: To clarify many people drive below the speed limit, in this case it is possible to pass them in a lane to the left without exceeding the speed limit.
  - kiril-me 10y ago
    In Europe fast traffic go left. If some one slow way it always overtaken on free lane.
  - geocar 10y ago
    It depends on the state. Some states do not permit undertaking. Others do.
  - treigerm 10y ago
    Here's a nice video that explains the concept quite well I think: https://www.youtube.com/watch?v=4oqfodY2Lz0 https://www.youtube.com/watch?v=4oqfodY2Lz0 (Title: Why you shouldn't drive slowly in the left lane)
    - aidos 10y ago
      There's an interesting British thing where lots of people are militant about lane positioning to the point of recklessness. I know otherwise down to earth people who absolutely loss it when there's someone in the middle lane on a motorway. I have friends who will pull close behind the offending vehicle, flash their lights, beep their horn and yell - which is obviously far more dangerous than the original offence. This is in cases where there's a totally empty "fast" lane further to the right. Many drivers almost feel entitled to not have someone in front of them in the middle lane. I get the argument for staying over to the left (in the UK). I'm not convinced that it's 100% rational though. Picture a normal scenario with 3 lanes and on/off ramps coming in from the left. With light traffic, all vehicles can keep to the left, over taking can happen in the middle lane and there's space for vehicles joining via the on-ramp. Fine. With really heavy traffic, you normally end up with 3 lanes of traffic moving at increasing speed to the right and all the lanes are utilised. Everyone seems happy. Fine. What happens with the murky space in between? If you try to stack everyone in the left lane they need to keep making space for people joining from the ramps. Also, some people will be moving faster than those in the far left, so they're effectively overtaking, but then where do you draw the line where they have to pull back to the left again (only to move out to overtake in another minute)? You could say that the moment there's any space to the left you move into it, but you just end up with lots more lane changes - which, at some point, becomes more dangerous than everyone just staying in the same lane. There's a balance to strike between changing to satisfy the rule and staying the course to decrease the amount of changing. For different people that line is in different places and for a lot of people I know who grew up in the UK, if they place your behaviour on the wrong side of that (arbitrary) line, there will be hell to pay. As a once foreigner it's all quite interesting.
      - stefs 10y ago
        observations from austria (remember we have the steering wheel on the right side ... so, the left). the law on the autobahn/multi-lane streets is: change to a lane on the left (a faster lane) only to overtake (except for special conditions, i.e. traffic jams/very slow moving). mostly south of vienna, the system is different though. due to the high amount of traffic from eastern neighboring states, with different rules and different speed limits (austrias autobahn speed limit is 130km/h, while in the east it's sometimes 120km/h, i'd guess), it's usually: * right lane (slowest): trucks and slow moving vehicles ~80-100km/h * middle lane: normal traffic, depending on weather ~110-120km/h (with sometimes up to 130-140km/h if traffic permits, usually not for long though) * left lane (fastest): traffic going faster (130km/h+) you choose the lane appropriate for your speed. overtaking strictly on the left. this is, strictly speaking, not legal. if the slower lane is free you have to change, even if you're going top speed. in the beginning i've been complaining about people not observing the local laws, but nowadays i have to admit that i think the eastern system works better.
  - nthcolumn 10y ago
    Driving in the UK is sheer hell. Most people drive in the middle lane regardless of whether they are overtaking or not. Go to the continent and it is pure bliss by comparison. Brits even mistakenly call the outer lane the 'fast' lane. It is actually the serious offense of 'Driving Without Due Care And Attention' but UK transport police are worse than useless. On education - there is no test of motorway/highway skills for your driving license! Also, many UK people even deliberately obstruct other road users. The law states that you _can_ undertake. It is detailed in what is known as the Highway Code. Undertaking is allowed in a one-way system eg. motorway provided the vehicle to your right is not overtaking e.g. maintaining a constant speed sitting in the damn lane like they own it making everybody else do their driving. I'll go now before rant mode fully kicks in....
    - popey456963 10y ago
      And yet the UK has the third lowest crash rate in the world compared with population and the second lowest crash compared per distance driven.[0] Also, your facts are wrong. You are required to practice on your highway skills and you will almost certainly go on a highway (if location permits) during your test. I'm almost happy we don't train our newer drivers on the motorway, honestly, I'm not sure I would trust them not to mess up even with an instructor joining them. We do have debates about whether to let newer drivers go on the motorway [1], but people bring up the point that they're normally incredibly busy and a single mistake could kill 5+ cars travelling at 70mph. Also, you say we can't call the outer lane the "fast" lane? It is fast when compared to the other lanes, but this doesn't mean we need to drive without care or attention! I think you don't understand that "fast" is a relative term and does not mean you can break the speed limit. A couple of other points: - You can't undertake normally, only in specific circumstances such as in queues or in separated traffic situations (like one-way traffic). You are NOT allowed to undertake on a motorway. - "Many UK people even deliberately obstruct other road users" has never happened to me in my life but, I've heard others talk about doing it to others when they're not being considerate to others (for example when two lanes go to one, and a car thinks they can speed down the fast lane to overtake everyone and just bully their way into the left lane). - "Pure bliss by comparison", really? Italy is notoriously bad at driving, Spain and other places also have similar problems with them. Generalising the entire continent to be perfect doesn't work. [0] https://en.wikipedia.org/wiki/List_of_countries_by_traffic-related_death_rate https://en.wikipedia.org/wiki/List_of_countries_by_traffic-r... [1] http://www.bbc.co.uk/news/uk-38464776 http://www.bbc.co.uk/news/uk-38464776
  - NietTim 10y ago
    But are there rules that disallow overtaking on the right?
    - cgriswald 10y ago
      For most states, those rules generally don't apply when the passing is happening in a lane of travel. Instead, they refer to situations like using an exit-only lane to pass, trying to pass in a gap between parked cars, or passing on the shoulder.
    - knicholes 10y ago
      In Utah, we can pass on the right as long as there are more than two lanes. If there are only two lanes, you are supposed to only pass on the left. As noted in other comments, this is state-based and I've never once seen it enforced.
    - techdmn 10y ago
      Strangely more people seem to know about this than about only using the left lanes to pass. I have seen several people get worked up about being passed on the right, to which my response is "why were you driving on the left"? They don't realize that the slower vehicle chooses the overtaking lane - whichever lane they aren't occupying. In my opinion it's down to the signage: "SLOWER TRAFFIC KEEP RIGHT". Nobody wants to think of themselves as slower. Should say "LEFT LANE FOR PASSING ONLY".
  - crispyambulance 10y ago
    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.
    - ygra 10y ago
      In Europe exits on the left of the motorway are quite rare (excluding countries that drive on the left).
  - btbuildem 10y ago
    The law is the same in the US -- but, your comment is quite telling.
- taneq 10y ago
  It's clearly a simulation of Western Australian traffic.
- __mp 10y ago
  I've been recently driving in Australia and the behavior is spot on. Cars were overtaking on the left (inner sode of the road) as well.
  - taneq 10y ago
    In states where it's legal to overtake on the left, there's no cultural obligation to stay in the leftmost unoccupied lane unless overtaking, and so cars end up scattered all over the lanes. Add in the government's myopic 30-year fixation on speed limits as the answer to any and all road trauma statistics (and their huge expenditure on propaganda to convince the general public) and you get self-righteous idiots doing 10-20km/h under the limit in the rightmost lanes smugly convincing themselves that they're "making the road safer" as road trains try weave around them.
  - lysp 10y ago
    As Australia drives on the opposite side to the USA - the general thing to do is slow cars move to the left and most overtaking is done in the "fast" / right lane(s). In practise though, people go slow in the right lanes and are not considerate of other drives. Some even think they have the right to prevent others from speeding and deliberately do 5-10km/h under the limit. The thing is, by not following the practise you cause other impatient drives (rightly or wrongly) to weave in and out of lanes passing on both sides which increases chances of an accident - due to the increase number of lane changes.
- mvindahl 10y ago
  Also, they all seem to be changing objectives and speed at random. In my experience (European highways), it's usually pretty easy to categorize other cars into different patterns of behaviour, such as "wants to move as fast as possible", "wants to save gas by staying below the speed limit, preferrably right behind a truck" or "trying to maintain preferred speed, changing lanes as needed". Also, most cars will act in a fairly safe and rational way: avoid tailgating, signal before lane changes, maintain speed and lane unless there is a good reason to change, try to stay clear of other cars which they find unsafe. It's an interesting system, actually, and one which is very much based upon experience and intuition. By contract, the cars in the simulation seem to change lanes and velocities all willy nilly. All of them flip my bozo bit and my intuitive reaction would be to position myself to take the closest possible exit ...
  - tonylemesmer 10y ago
    have you driven on a UK motorway recently? tailgating? yep cutting into traffic? yep randomly slowing down and speeding up? yep
- andy_ppp 10y ago
  My particular pet peeve is being undertaken by fellow cyclists! It's not like I'm even going slowly!
  - adrianoconnor 10y ago
    Undertaken? How far out in the road are you riding? I've never undertaken a fellow cyclist in my life, out on the open road, and I can't think that I've ever seen it done.
    - andy_ppp 10y ago
      Quite common on roundabouts or when parked cars are on my inside; I've seen too many people nearly killed by the sudden opening of a car door into their path. On roundabouts I try to take up the whole lane so drivers know what you are doing and don't assume you are turning off. I could probably write a book about defensive cycling; the amount of times drivers would have turned into me if I wasn't predicting it is probably over 50... it's the most common way to be killed.
- SixSigma 10y ago
  Come to Miami. There is zero lane discipline.
- randomnumber314 10y ago
  |Why is everybody driving in random lanes? Because that's closer to how humans drive. As infuriating as it is, midwest-USA traffic follows almost no rules about what the left lanes are for.
  - dawnerd 10y ago
    Varies by state too. Not every state requires people to keep right.
- Fnoord 10y ago
  > Why is everybody driving in random lanes? You should only go into the outer lanes to overtake traffic And if you need to exit the road. Or if you think you need to Soon (tm). As someone else already put: in Europe you need to drive at the outer lanes (usually right, UK left lanes) if you're slow, and if you want to overtake traffic you move inward (usually left, UK right lanes) after which you should ASAP move back to the outer lane. Its logical that people from MIT try to emulate US traffic or even Massachusetts traffic though.
- mbrookes 10y ago
  > You should only go into the outer lanes to overtake traffic, and then move back in once you've passed. Not in the US AFAIK (or does it vary by state?). My understanding and experience is that driving in the lane of your choice, and "undertaking" (overtaking on the inside) are both legal and common practice.
  - pdx 10y ago
    You are incorrect, but I can see why you would be confused, since so many people pick the left lane to go slow in. I think they imagine themselves to be some sort of force for good, slowing down all those evil speeders. Here's a summary of the law, by state. http://www.mit.edu/~jfc/right.html http://www.mit.edu/~jfc/right.html
    - mbrookes 10y ago
      Huh, interesting. So it's a law that is neither obeyed nor enforced (in my limited experience).
    - deleted 10y ago
      [deleted]
- stuckagain 10y ago
  That's a simplistic application of lane discipline principle to a 7-lane road. I'm sure you aren't advocating for everyone to drive in the rightmost except when overtaking. The question then becomes one of acceptable gradient. How much faster do I need to go to warrant the use of the lane to my left? Is there a quantum? In America the accepted answers are "none" and "no". Also a 7-lane road is a terrible idea.
rawnlq 10y ago
I wonder how simulations like this transfer to the real world. For example if you want to win in the real world you just start driving like a maniac. People will very quickly get out of dodge. Spoilers: I tried to encode this idea by setting the inputs to be just tall enough to learn the safety system and wide enough to cover all lanes with no forward visibility. This learns an aggressive lane switching algorithm that lets you hit around ~70mph though not for the reason I thought. Also needed a few more hidden units/layers to make it work.
- indeed30 10y ago
  Yes, similar experiences here. It seems relatively easy to hit the 70mph mark but it gets tough past that.
screwt 10y ago
For self-driving cars, I'd much rather your code control _all_ the cars, not just an individual. Individualistic driving leads to worse overall performance for everyone. One of the things I'm most looking forward to in an all-code-controlled driving future is seeing efficient highway traffic moving fast and smoothly. (And yes, clearly there's a long transition period where some cars are controlled while others are still human-driven.)
- jstanley 10y ago
  > I'd much rather your code control _all_ the cars, not just an individual. That's not how the world works though. The only thing you can control is your own actions. Trying to control other people's actions is a recipe for failure.
  - kuschku 10y ago
    > Trying to control other people's actions is a recipe for failure. Trying to control other people’s actions is called a law.
    - A_Crazy_Idea 10y ago
      Also known as industry standard
- vbezhenar 10y ago
  Another advantage is that pedestrians can just walk wherever they want and cars will safely avoid them. Much more freedom for everyone.
- wyldfire 10y ago
  > (And yes, clearly there's a long transition period After that transition period, the automobile designers will start to optimize for a use case where the majority of the traffic is autonomous and agree on standards of how to align the different designs' goals. It seems like that tipping point is so far away as to not make sense spending time on now. And I imagine even a century from now you will still see some vehicles driven by humans. There will always be exceptional transportation use cases, including cases where the autonomous vehicles forfeit control because of confusion or material defect (bad sensors, weather, etc).
deleted 10y ago
[deleted]
czbond 10y ago
Can someone help me understand - why is this in JS? [I'm asking seriously, not trying to start a language troll-war]. I ask because I'm designing a system that could use JS trained models (for wider company access) - yet I was unaware of tools that can run models at scale using JS (i've seen more in Python, R).
- azdle 10y ago
  Because it's about teaching, not about getting the best possible performance. JS based stuff is easy to get working, because it's just "install chrome, go to <webpage>".
  - czbond 10y ago
    Fantastic I'm all about that. I wanted to make sure there hasn't been a leap in language tools that I missed. Thanks.
- martincmartin 10y ago
  I'm guessing its so that it runs in the users browser (using their computing resources), rather than on MITs computers. If you get a lot of users, the difference could be very important.
djb_hackernews 10y ago
I was able to get speeds of 71 MPH, now can anyone tell me exactly what I did because my approach was just to randomly change values, train and run. I read the documentation and watched the first video and read all of the lecture slides but I haven't really grasped any of the concepts. Like, is 400 num_neurons a lot? Not a lot? Why would looking backward help at all? Why have that as a variable? It suggests to increase the train_iterations from 10000. Does that mean 15k, 100k, 1000k? Was that the point of the exercise, just to get comfortable with making changes and running simulations or should I have come away with a deeper understanding? If anyone feels like they could teach me I'd be willing to pay $100 for a half hour of your time, skype or Cambridge/Boston if you are local.
- A_Crazy_Idea 10y ago
  Clearly what you need is an opinion of a qualified professional.
- kostyan5 10y ago
  Do this course and you'll get a very good idea of what's happening, and it's free: https://www.coursera.org/learn/machine-learning https://www.coursera.org/learn/machine-learning
- lawless123 10y ago
  400 num_neurons is quite a lot, i trained a facial expression classifier in college a few years ago from images i got Online. That was for a basic feed forward classifier though, this is different. The input layer was large but the hidden layer was only 12 neurons. I'm still learning myself so i wouldn't be able to teach you. There are some great courses online.
  - brianchu 10y ago
    400 units is very small. Today's image classification neural nets have hundreds of thousands of units (units is my preferred non-biological synonym for "neuron")
    - 10y ago
Chris2048 10y ago
So, Is the idea that some autonomous cars could just drive around doing nothing other than setting the pace?
gefh 10y ago
From the source, for those who are wondering what 'fc' or 'relu' mean: case 'fc': this.layers.push(new global.FullyConnLayer(def)); break; case 'lrn': this.layers.push(new global.LocalResponseNormalizationLayer(def)); break; case 'dropout': this.layers.push(new global.DropoutLayer(def)); break; case 'input': this.layers.push(new global.InputLayer(def)); break; case 'softmax': this.layers.push(new global.SoftmaxLayer(def)); break; case 'regression': this.layers.push(new global.RegressionLayer(def)); break; case 'conv': this.layers.push(new global.ConvLayer(def)); break; case 'pool': this.layers.push(new global.PoolLayer(def)); break; case 'relu': this.layers.push(new global.ReluLayer(def)); break; case 'sigmoid': this.layers.push(new global.SigmoidLayer(def)); break; case 'tanh': this.layers.push(new global.TanhLayer(def)); break; case 'maxout': this.layers.push(new global.MaxoutLayer(def)); break; case 'svm': this.layers.push(new global.SVMLayer(def)); break;

180 points by kiril-me 10y ago

8 lanes is easy Try driving in 2 lanes with random people switching lanes in front of you, people randomly blocking your lane to turn, etc, also make sure you get into your destination on time

jstanley 10y ago

Why is everybody driving in random lanes? You should only go into the outer lanes to overtake traffic, and then move back in once you've passed. It's not just the law, it's a good idea... EDIT: And for anyone looking for more info, this seems to be a more useful page: http://selfdrivingcars.mit.edu/deeptraffic/ http://selfdrivingcars.mit.edu/deeptraffic/

fatuna 10y ago
As far as I know, it is common in Europe to only overtake on the outer lanes. In the US however, there are no such rules. It does seem like a good idea to me.
- splike 10y ago
  The law exists in the US, but nobody bothers to follow it from my experience driving there. People just seem to use the other lanes as more road.
  - nrjdhsbsid 10y ago
    It's pretty well followed on the highway in low traffic conditions. Trucks and such will stay right. During heavy traffic nobody gives a flying fuck though, and I've never heard of the law being enforced once if it wasn't a charge being tacked onto something else like reckless driving
    - 6DM 10y ago
      On top of that, there will always be "sections" of the road where traffic reliably grinds to a halt. So people keep switching back and forth to avoid those areas.
  - seanmcdirmid 10y ago
    The US does not have one set of traffic laws for all states.
    - maxerickson 10y ago
      Most states follow the Uniform Vehicle Code on this issue http://jalopnik.com/5501615/left-lane-passing-laws-a-state-by-state-map http://jalopnik.com/5501615/left-lane-passing-laws-a-state-b... (and among those that don't 1/2 of them still have laws about obstructing traffic)
      - dsp1234 10y ago
        The issue mentioned in your linked article is different from what's mentioned up thread. The article deals with "what is the role of the very left lane". Upthread it's about using non-outer lanes (inner lanes) as the passing lane, which implies passing on the right. The UVC specifically allows passing on the right on a paved road with 2, or more, lanes (see 11-304(a)(2))
        maxerickson 10y ago
        jstanley at the top of the thread is clearly talking about the same thing as my article, keeping right except when passing. You should only go into the outer lanes to overtake traffic, and then move back in once you've passed. It's not just the law, it's a good idea... That's not about passing on the right.
        dsp1234 10y ago
        The outer lanes are the left and right lanes. Which implies that, given 3 lanes, someone is passing on the right. At a base level, given more than 2 lanes, there is a difference between "stay out of the left lane unless passing", and "stay out of the left and right lanes unless passing", as it gives drivers twice as many options for passing.
        10y ago
  - virgil_disgr4ce 10y ago
    What I've never understood about this idea is that it suggests that speeding must not be illegal in that passing lane. But that's not true. So then how does a law for a passing lane work?
    - mulmen 10y ago
      I'm not sure where you get the suggestion that there is no speed limit in the passing lane. We drive on the right so the safest place to pass is on the left where the driver is. If everyone stays right as much as possible and faster traffic (this does not imply speeding) can move left to pass then traffic flows smoothly. Where are you getting the impression that speeding is allowed anywhere?
      - nkurz 10y ago
        > Where are you getting the impression that speeding is allowed anywhere? One reason is that in many places in the US, the normal traffic speed exceeds the legal posted limit by 5-15 miles per hour. If the law requires a driver travelling at the legal speed limit to stay out of the "passing lane" so that other drivers can pass, this would imply that the law condones speeding, since only a driver moving faster than the legal speed limit can make use of that lane. If the law was not intended to encourage exceeding the speed limit, it likely would have been written as something like "any driver moving less the legal speed limit must avoid the passing lane". Another reason is that some US states make exceptions to the normal speed limit when passing another vehicle on a two lane road: http://blog.seattlepi.com/seattle911/2014/10/10/can-i-speed-while-passing/ http://blog.seattlepi.com/seattle911/2014/10/10/can-i-speed-..., http://www.mlive.com/news/index.ssf/2012/03/traffic_talk_comments_should_t_1.html http://www.mlive.com/news/index.ssf/2012/03/traffic_talk_com.... While one could argue that it's not "speeding" if it's not illegal, it's not unreasonable to interpret such laws as "allowing speeding" to pass.
        mulmen 10y ago
        > If the law requires a driver travelling at the legal speed limit to stay out of the "passing lane" so that other drivers can pass, this would imply that the law condones speeding, since only a driver moving faster than the legal speed limit can make use of that lane. That's not how it works. The law is "stay right except to pass". This is true regardless of speed. Speeding is still illegal in any lane. The "stay right" rule is about not obstructing the flow of traffic, it has nothing to do with the posted speed limit. e: To clarify many people drive below the speed limit, in this case it is possible to pass them in a lane to the left without exceeding the speed limit.
- kiril-me 10y ago
  In Europe fast traffic go left. If some one slow way it always overtaken on free lane.
- geocar 10y ago
  It depends on the state. Some states do not permit undertaking. Others do.
- treigerm 10y ago
  Here's a nice video that explains the concept quite well I think: https://www.youtube.com/watch?v=4oqfodY2Lz0 https://www.youtube.com/watch?v=4oqfodY2Lz0 (Title: Why you shouldn't drive slowly in the left lane)
  - aidos 10y ago
    There's an interesting British thing where lots of people are militant about lane positioning to the point of recklessness. I know otherwise down to earth people who absolutely loss it when there's someone in the middle lane on a motorway. I have friends who will pull close behind the offending vehicle, flash their lights, beep their horn and yell - which is obviously far more dangerous than the original offence. This is in cases where there's a totally empty "fast" lane further to the right. Many drivers almost feel entitled to not have someone in front of them in the middle lane. I get the argument for staying over to the left (in the UK). I'm not convinced that it's 100% rational though. Picture a normal scenario with 3 lanes and on/off ramps coming in from the left. With light traffic, all vehicles can keep to the left, over taking can happen in the middle lane and there's space for vehicles joining via the on-ramp. Fine. With really heavy traffic, you normally end up with 3 lanes of traffic moving at increasing speed to the right and all the lanes are utilised. Everyone seems happy. Fine. What happens with the murky space in between? If you try to stack everyone in the left lane they need to keep making space for people joining from the ramps. Also, some people will be moving faster than those in the far left, so they're effectively overtaking, but then where do you draw the line where they have to pull back to the left again (only to move out to overtake in another minute)? You could say that the moment there's any space to the left you move into it, but you just end up with lots more lane changes - which, at some point, becomes more dangerous than everyone just staying in the same lane. There's a balance to strike between changing to satisfy the rule and staying the course to decrease the amount of changing. For different people that line is in different places and for a lot of people I know who grew up in the UK, if they place your behaviour on the wrong side of that (arbitrary) line, there will be hell to pay. As a once foreigner it's all quite interesting.
    - stefs 10y ago
      observations from austria (remember we have the steering wheel on the right side ... so, the left). the law on the autobahn/multi-lane streets is: change to a lane on the left (a faster lane) only to overtake (except for special conditions, i.e. traffic jams/very slow moving). mostly south of vienna, the system is different though. due to the high amount of traffic from eastern neighboring states, with different rules and different speed limits (austrias autobahn speed limit is 130km/h, while in the east it's sometimes 120km/h, i'd guess), it's usually: * right lane (slowest): trucks and slow moving vehicles ~80-100km/h * middle lane: normal traffic, depending on weather ~110-120km/h (with sometimes up to 130-140km/h if traffic permits, usually not for long though) * left lane (fastest): traffic going faster (130km/h+) you choose the lane appropriate for your speed. overtaking strictly on the left. this is, strictly speaking, not legal. if the slower lane is free you have to change, even if you're going top speed. in the beginning i've been complaining about people not observing the local laws, but nowadays i have to admit that i think the eastern system works better.
- nthcolumn 10y ago
  Driving in the UK is sheer hell. Most people drive in the middle lane regardless of whether they are overtaking or not. Go to the continent and it is pure bliss by comparison. Brits even mistakenly call the outer lane the 'fast' lane. It is actually the serious offense of 'Driving Without Due Care And Attention' but UK transport police are worse than useless. On education - there is no test of motorway/highway skills for your driving license! Also, many UK people even deliberately obstruct other road users. The law states that you _can_ undertake. It is detailed in what is known as the Highway Code. Undertaking is allowed in a one-way system eg. motorway provided the vehicle to your right is not overtaking e.g. maintaining a constant speed sitting in the damn lane like they own it making everybody else do their driving. I'll go now before rant mode fully kicks in....
  - popey456963 10y ago
    And yet the UK has the third lowest crash rate in the world compared with population and the second lowest crash compared per distance driven.[0] Also, your facts are wrong. You are required to practice on your highway skills and you will almost certainly go on a highway (if location permits) during your test. I'm almost happy we don't train our newer drivers on the motorway, honestly, I'm not sure I would trust them not to mess up even with an instructor joining them. We do have debates about whether to let newer drivers go on the motorway [1], but people bring up the point that they're normally incredibly busy and a single mistake could kill 5+ cars travelling at 70mph. Also, you say we can't call the outer lane the "fast" lane? It is fast when compared to the other lanes, but this doesn't mean we need to drive without care or attention! I think you don't understand that "fast" is a relative term and does not mean you can break the speed limit. A couple of other points: - You can't undertake normally, only in specific circumstances such as in queues or in separated traffic situations (like one-way traffic). You are NOT allowed to undertake on a motorway. - "Many UK people even deliberately obstruct other road users" has never happened to me in my life but, I've heard others talk about doing it to others when they're not being considerate to others (for example when two lanes go to one, and a car thinks they can speed down the fast lane to overtake everyone and just bully their way into the left lane). - "Pure bliss by comparison", really? Italy is notoriously bad at driving, Spain and other places also have similar problems with them. Generalising the entire continent to be perfect doesn't work. [0] https://en.wikipedia.org/wiki/List_of_countries_by_traffic-related_death_rate https://en.wikipedia.org/wiki/List_of_countries_by_traffic-r... [1] http://www.bbc.co.uk/news/uk-38464776 http://www.bbc.co.uk/news/uk-38464776
- NietTim 10y ago
  But are there rules that disallow overtaking on the right?
  - cgriswald 10y ago
    For most states, those rules generally don't apply when the passing is happening in a lane of travel. Instead, they refer to situations like using an exit-only lane to pass, trying to pass in a gap between parked cars, or passing on the shoulder.
  - knicholes 10y ago
    In Utah, we can pass on the right as long as there are more than two lanes. If there are only two lanes, you are supposed to only pass on the left. As noted in other comments, this is state-based and I've never once seen it enforced.
  - techdmn 10y ago
    Strangely more people seem to know about this than about only using the left lanes to pass. I have seen several people get worked up about being passed on the right, to which my response is "why were you driving on the left"? They don't realize that the slower vehicle chooses the overtaking lane - whichever lane they aren't occupying. In my opinion it's down to the signage: "SLOWER TRAFFIC KEEP RIGHT". Nobody wants to think of themselves as slower. Should say "LEFT LANE FOR PASSING ONLY".
- crispyambulance 10y ago
  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.
  - ygra 10y ago
    In Europe exits on the left of the motorway are quite rare (excluding countries that drive on the left).
- btbuildem 10y ago
  The law is the same in the US -- but, your comment is quite telling.
taneq 10y ago
It's clearly a simulation of Western Australian traffic.
__mp 10y ago
I've been recently driving in Australia and the behavior is spot on. Cars were overtaking on the left (inner sode of the road) as well.
- taneq 10y ago
  In states where it's legal to overtake on the left, there's no cultural obligation to stay in the leftmost unoccupied lane unless overtaking, and so cars end up scattered all over the lanes. Add in the government's myopic 30-year fixation on speed limits as the answer to any and all road trauma statistics (and their huge expenditure on propaganda to convince the general public) and you get self-righteous idiots doing 10-20km/h under the limit in the rightmost lanes smugly convincing themselves that they're "making the road safer" as road trains try weave around them.
- lysp 10y ago
  As Australia drives on the opposite side to the USA - the general thing to do is slow cars move to the left and most overtaking is done in the "fast" / right lane(s). In practise though, people go slow in the right lanes and are not considerate of other drives. Some even think they have the right to prevent others from speeding and deliberately do 5-10km/h under the limit. The thing is, by not following the practise you cause other impatient drives (rightly or wrongly) to weave in and out of lanes passing on both sides which increases chances of an accident - due to the increase number of lane changes.
mvindahl 10y ago
Also, they all seem to be changing objectives and speed at random. In my experience (European highways), it's usually pretty easy to categorize other cars into different patterns of behaviour, such as "wants to move as fast as possible", "wants to save gas by staying below the speed limit, preferrably right behind a truck" or "trying to maintain preferred speed, changing lanes as needed". Also, most cars will act in a fairly safe and rational way: avoid tailgating, signal before lane changes, maintain speed and lane unless there is a good reason to change, try to stay clear of other cars which they find unsafe. It's an interesting system, actually, and one which is very much based upon experience and intuition. By contract, the cars in the simulation seem to change lanes and velocities all willy nilly. All of them flip my bozo bit and my intuitive reaction would be to position myself to take the closest possible exit ...
- tonylemesmer 10y ago
  have you driven on a UK motorway recently? tailgating? yep cutting into traffic? yep randomly slowing down and speeding up? yep
andy_ppp 10y ago
My particular pet peeve is being undertaken by fellow cyclists! It's not like I'm even going slowly!
- adrianoconnor 10y ago
  Undertaken? How far out in the road are you riding? I've never undertaken a fellow cyclist in my life, out on the open road, and I can't think that I've ever seen it done.
  - andy_ppp 10y ago
    Quite common on roundabouts or when parked cars are on my inside; I've seen too many people nearly killed by the sudden opening of a car door into their path. On roundabouts I try to take up the whole lane so drivers know what you are doing and don't assume you are turning off. I could probably write a book about defensive cycling; the amount of times drivers would have turned into me if I wasn't predicting it is probably over 50... it's the most common way to be killed.
SixSigma 10y ago
Come to Miami. There is zero lane discipline.
randomnumber314 10y ago
|Why is everybody driving in random lanes? Because that's closer to how humans drive. As infuriating as it is, midwest-USA traffic follows almost no rules about what the left lanes are for.
- dawnerd 10y ago
  Varies by state too. Not every state requires people to keep right.
Fnoord 10y ago
> Why is everybody driving in random lanes? You should only go into the outer lanes to overtake traffic And if you need to exit the road. Or if you think you need to Soon (tm). As someone else already put: in Europe you need to drive at the outer lanes (usually right, UK left lanes) if you're slow, and if you want to overtake traffic you move inward (usually left, UK right lanes) after which you should ASAP move back to the outer lane. Its logical that people from MIT try to emulate US traffic or even Massachusetts traffic though.
mbrookes 10y ago
> You should only go into the outer lanes to overtake traffic, and then move back in once you've passed. Not in the US AFAIK (or does it vary by state?). My understanding and experience is that driving in the lane of your choice, and "undertaking" (overtaking on the inside) are both legal and common practice.
- pdx 10y ago
  You are incorrect, but I can see why you would be confused, since so many people pick the left lane to go slow in. I think they imagine themselves to be some sort of force for good, slowing down all those evil speeders. Here's a summary of the law, by state. http://www.mit.edu/~jfc/right.html http://www.mit.edu/~jfc/right.html
  - mbrookes 10y ago
    Huh, interesting. So it's a law that is neither obeyed nor enforced (in my limited experience).
  - deleted 10y ago
    [deleted]
stuckagain 10y ago
That's a simplistic application of lane discipline principle to a 7-lane road. I'm sure you aren't advocating for everyone to drive in the rightmost except when overtaking. The question then becomes one of acceptable gradient. How much faster do I need to go to warrant the use of the lane to my left? Is there a quantum? In America the accepted answers are "none" and "no". Also a 7-lane road is a terrible idea.

rawnlq 10y ago

I wonder how simulations like this transfer to the real world. For example if you want to win in the real world you just start driving like a maniac. People will very quickly get out of dodge. Spoilers: I tried to encode this idea by setting the inputs to be just tall enough to learn the safety system and wide enough to cover all lanes with no forward visibility. This learns an aggressive lane switching algorithm that lets you hit around ~70mph though not for the reason I thought. Also needed a few more hidden units/layers to make it work.

indeed30 10y ago
Yes, similar experiences here. It seems relatively easy to hit the 70mph mark but it gets tough past that.

screwt 10y ago

For self-driving cars, I'd much rather your code control _all_ the cars, not just an individual. Individualistic driving leads to worse overall performance for everyone. One of the things I'm most looking forward to in an all-code-controlled driving future is seeing efficient highway traffic moving fast and smoothly. (And yes, clearly there's a long transition period where some cars are controlled while others are still human-driven.)

jstanley 10y ago
> I'd much rather your code control _all_ the cars, not just an individual. That's not how the world works though. The only thing you can control is your own actions. Trying to control other people's actions is a recipe for failure.
- kuschku 10y ago
  > Trying to control other people's actions is a recipe for failure. Trying to control other people’s actions is called a law.
  - A_Crazy_Idea 10y ago
    Also known as industry standard
vbezhenar 10y ago
Another advantage is that pedestrians can just walk wherever they want and cars will safely avoid them. Much more freedom for everyone.
wyldfire 10y ago
> (And yes, clearly there's a long transition period After that transition period, the automobile designers will start to optimize for a use case where the majority of the traffic is autonomous and agree on standards of how to align the different designs' goals. It seems like that tipping point is so far away as to not make sense spending time on now. And I imagine even a century from now you will still see some vehicles driven by humans. There will always be exceptional transportation use cases, including cases where the autonomous vehicles forfeit control because of confusion or material defect (bad sensors, weather, etc).

deleted 10y ago

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czbond 10y ago

Can someone help me understand - why is this in JS? [I'm asking seriously, not trying to start a language troll-war]. I ask because I'm designing a system that could use JS trained models (for wider company access) - yet I was unaware of tools that can run models at scale using JS (i've seen more in Python, R).

azdle 10y ago
Because it's about teaching, not about getting the best possible performance. JS based stuff is easy to get working, because it's just "install chrome, go to <webpage>".
- czbond 10y ago
  Fantastic I'm all about that. I wanted to make sure there hasn't been a leap in language tools that I missed. Thanks.
martincmartin 10y ago
I'm guessing its so that it runs in the users browser (using their computing resources), rather than on MITs computers. If you get a lot of users, the difference could be very important.

djb_hackernews 10y ago

I was able to get speeds of 71 MPH, now can anyone tell me exactly what I did because my approach was just to randomly change values, train and run. I read the documentation and watched the first video and read all of the lecture slides but I haven't really grasped any of the concepts. Like, is 400 num_neurons a lot? Not a lot? Why would looking backward help at all? Why have that as a variable? It suggests to increase the train_iterations from 10000. Does that mean 15k, 100k, 1000k? Was that the point of the exercise, just to get comfortable with making changes and running simulations or should I have come away with a deeper understanding? If anyone feels like they could teach me I'd be willing to pay $100 for a half hour of your time, skype or Cambridge/Boston if you are local.

A_Crazy_Idea 10y ago
Clearly what you need is an opinion of a qualified professional.
kostyan5 10y ago
Do this course and you'll get a very good idea of what's happening, and it's free: https://www.coursera.org/learn/machine-learning https://www.coursera.org/learn/machine-learning
lawless123 10y ago
400 num_neurons is quite a lot, i trained a facial expression classifier in college a few years ago from images i got Online. That was for a basic feed forward classifier though, this is different. The input layer was large but the hidden layer was only 12 neurons. I'm still learning myself so i wouldn't be able to teach you. There are some great courses online.
- brianchu 10y ago
  400 units is very small. Today's image classification neural nets have hundreds of thousands of units (units is my preferred non-biological synonym for "neuron")
  - 10y ago

Chris2048 10y ago

So, Is the idea that some autonomous cars could just drive around doing nothing other than setting the pace?

gefh 10y ago

From the source, for those who are wondering what 'fc' or 'relu' mean: case 'fc': this.layers.push(new global.FullyConnLayer(def)); break; case 'lrn': this.layers.push(new global.LocalResponseNormalizationLayer(def)); break; case 'dropout': this.layers.push(new global.DropoutLayer(def)); break; case 'input': this.layers.push(new global.InputLayer(def)); break; case 'softmax': this.layers.push(new global.SoftmaxLayer(def)); break; case 'regression': this.layers.push(new global.RegressionLayer(def)); break; case 'conv': this.layers.push(new global.ConvLayer(def)); break; case 'pool': this.layers.push(new global.PoolLayer(def)); break; case 'relu': this.layers.push(new global.ReluLayer(def)); break; case 'sigmoid': this.layers.push(new global.SigmoidLayer(def)); break; case 'tanh': this.layers.push(new global.TanhLayer(def)); break; case 'maxout': this.layers.push(new global.MaxoutLayer(def)); break; case 'svm': this.layers.push(new global.SVMLayer(def)); break;