
Google's driverless cars designed to exceed speed limit - lsh123
http://www.bbc.com/news/technology-28851996
======
georgemcbay
Good.

It would be stupid not to, especially during the transition phase where
driverless cars are the minority.

YMMV depending upon local standards but here in San Diego, CA it is extremely
common for the flow the traffic to be going 5-15 miles above posted speed
limits and the cops do not care. Having a car going significantly slower than
the flow of traffic is much worse than exceeding the speed limit.

Also there are sometimes situations where very temporarily exceeding the limit
is the best option (eg. you're at the speed limit and someone cuts into your
lane toward the back of your car, potentially shunting you and you have no
clearance on the other side, but do have room up front). Driverless cars with
full 360 (or close to it) lidar would be ideal for dealing with this situation
(as opposed to a human driver that is unlikely to even see the other car in
his/her blindspot) but if they are capped at the speed limit their options for
resolving the situation safely would be severely curtailed.

~~~
josephschmoe
Definitely. I wouldn't want my car driving in an unsafe manner just to follow
local ordinances.

I'd be very curious if I could sue those local governments for endangering me
if my vehicle is forced to follow their rules and gets in an avoidable
accident because of them. It would be an eminent domain defense, in the sense
that government can't deny me of my property without a justifiable (public
safety) reason for doing so.

And forcing my computer to behave in a certain way that causes it to
potentially harm itself is definitely a denial of property.

I'm sure they'll just write me a ticket though - and if no one has gotten out
of that by citing statistics on road safety, my autonomous car won't be any
better off.

Hopefully, this will all be resolved reasonably with a national law and a nice
bug report interface on Google's part.

------
Chinjut
"Google's self-driving cars are programmed to exceed speed limits by up to
10mph (16km/h), according to the project's lead software engineer. Dmitri
Dolgov told Reuters that when surrounding vehicles were breaking the speed
limit, going more slowly could actually present a danger, and the Google car
would accelerate to keep up."

Clicking through to the source: "Google's driverless car is programmed to stay
within the speed limit, mostly. Research shows that sticking to the speed
limit when other cars are going much faster actually can be dangerous, Dolgov
says, so its autonomous car can go up to 10 mph (16 kph) above the speed limit
when traffic conditions warrant."

------
sbierwagen
I'm a dilettante hypermiler, ([http://en.wikipedia.org/wiki/Energy-
efficient_driving](http://en.wikipedia.org/wiki/Energy-efficient_driving))
which is mostly about driving slowly. And wow, it's amazing how mad some
people get when you drive the posted speed limit.

~~~
jfuhrman
Going the speed limit or lower in the passing lane, especially in rush hour is
dangerous and probably causes more accidents than just going a bit faster or
moving over to the other lanes when someone gets too close.

[http://www.dailymail.co.uk/news/article-2016721/Slow-
drivers...](http://www.dailymail.co.uk/news/article-2016721/Slow-drivers-
dangerous-roads-cause-crashes.html)

~~~
talmand
If a person is obeying the speed limit in the left lane and a crash ensues, it
is not the fault of the person obeying the speed limit. They may be guilty of
obstructing traffic in some way depending on the situation and the local laws
dictating the proper usage of the left lane, but not the accident.

Going slower? Possible, depends on how much slower.

~~~
mjevans
The left most lane (excluding HOV lanes) is for /passing/. Unless you are
passing you should NOT be in this lane. Remaining in this lane, even doing the
speed limit, while someone is behind you clearly wanting to go faster (that's
their problem, not your's) is failure to yield.

~~~
dragonwriter
> The left most lane (excluding HOV lanes) is for /passing/. Unless you are
> passing you should NOT be in this lane.

This is not generally the case.

[http://www.mit.edu/~jfc/right.html](http://www.mit.edu/~jfc/right.html)

~~~
na85
The law is not always in touch with reality. Regardless of where you drive, if
there are people behind you in the left lane, you should move over to let them
pass.

Don't piss people off unnecessarily for no reason other than to prove a point.

Move to the right.

~~~
JoeAltmaier
Here's the breakdown for the US states:
[http://www.mit.edu/~jfc/right.html](http://www.mit.edu/~jfc/right.html)

~~~
talmand
Why is Michigan listed as "weird" for having a straight-forward and sensible
rule?

~~~
dragonwriter
If you click through to the actual law, its weird in terms of the
categorization since it doesn't use any of the standard rubrics. The rule
applicable to roads with more than two lanes in the same direction is neither
a "left lane for passing" rule, or a "yield left lane to faster moving
traffic" rule or a "must keep up with normal speed for the road except in the
rightmost lane" rule. Its a "you must always drive exclusively in the
rightmost lane no matter how many are available, unless there is
'substantially continuous' traffic in the lane, or you are using the left lane
for turning."

It might be straight-forward and sensible (that, particularly the latter, is
particularly subjective), but its very distant conceptually from the rules
commonly used elsewhere that form the basis for the categorization and thus
is, in context, weird.

------
lsh123
Just curios if Google is going to pay the ticket if a cop stops the car.

~~~
talmand
I've seen similar questions arise from the thought of accidents. If a self-
driving car causes a crash, who's responsible? The owner or the manufacturer?

Another random thought: do the cars respond to a police officer trying to pull
them over?

~~~
krapp
>If a self-driving car causes a crash, who's responsible? The owner or the
manufacturer?

My two cents: if the car has the capacity for manual override, the owner
(negligence) otherwise the manufacturer.

>do the cars respond to a police officer trying to pull them over?

Legally, humans are supposed to, so why would it be different for self-driving
cars (which can at least be _programmed_ to give control over to a third party
when requested?)

~~~
TheLoneWolfling
> if the car has the capacity for manual override, the owner (negligence)

There are plenty of ways a self-driving car could mess up and cause an
accident _where you do not have enough time_ to react to it. Not "you should
have been paying more attention". As in "You are not superhuman enough to
react in time, period".

Say, swerving on the highway into oncoming traffic. Some (incredibly rough)
numbers: if you're going 108km/h and the car suddenly swerves into the other
lane of a two-lane highway, if it's 20m between start of swerve and hitting
the vehicle in the other lane, that's 2/3 of a second. _You can 't do that_.
You (or rather, an average person) are not going to be able to recover in
time. The reaction time for an alert driver is something like 0.7s on average.
[1]

And that's not the most pessimistic assumptions either.

[1] First link I found: [http://www.technology-assoc.com/articles/reaction-
time.html](http://www.technology-assoc.com/articles/reaction-time.html)

~~~
krapp
Maybe. I can imagine that in any other circumstance that the driver would be
liable where they would be considered liable in a standard car. But of course
if the self-driving car makes it impossible to react then that probably lies
on the manufacturer. At that point you might as well blame the passenger of a
commercial airliner for the autopilot going wrong.

------
luos
Would these cars overtake others, for example if there is a car towing an
other on a one lane (each way) road going significantly under the speed limit?

------
helpbygrace
Is this speed measured by GPS or vehicle?

In my experience, even though speedmeter in the instrument panel shows 10mph
over, actual GPS speed is around speed limit.

~~~
jimmcslim
According to the Wikipedia page on speedometers, under the Error heading...

'Vehicle manufacturers usually calibrate speedometers to read high by an
amount equal to the average error, to ensure that their speedometers never
indicate a lower speed than the actual speed of the vehicle, to ensure they
are not liable for drivers violating speed limits.', although no citation is
currently provided.

Error is introduced by tire diameter being different than what was assumed for
initial calibration... i.e. wear on the tires or tires that are under/over-
inflated.

[http://en.wikipedia.org/wiki/Speedometer](http://en.wikipedia.org/wiki/Speedometer)

------
elwell
> when surrounding vehicles were breaking the speed limit ... the Google car
> would accelerate to keep up
    
    
      for n, neighbor of neighbors
        if neighbor.vel > @vel # TODO: add something like: " and @vel < maxVel"
          @vel += 1
    

Just don't forget to grep for "TODO".

~~~
rumbler
If Amazon were to make a driverless car, I'd worry.

[http://www.pcmag.com/article2/0,2817,2384102,00.asp](http://www.pcmag.com/article2/0,2817,2384102,00.asp)

~~~
Turing_Machine
Despite the title, that's not an "Amazon algorithm". That's two third-party
sellers operating buggy software.

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allochthon
This link got thumped way down really quickly. And it's an interesting one.

