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How would you reduce speeding by car drivers?
I was reading this twitter post and it made me wonder if you have any ideas to stop speeding by car drivers? Have any of these ideas been tried anywhere? I'm also interested in unintended consequences.
https://twitter.com/agnessjonsson/status/1229103764843438086?s=20
Agnes @agnessjonsson
fact of the day: Sweden once experimented with a “speed camera lottery”. Those who drove within the speed limit were automatically entered into a drawing where the prize fund came from fines that speeders paid.
They tested it in a few different cities and I haven’t read the results of each one, but in Stockholm the average speed on the selected road decreased by 22 percent.
I mean, personally, I am of the opinion that New Zealand's speed limits are too slow in a lot of areas. We have some decent quality highways and roads that are limited to 100km/h, or even 80km/h which drives me nuts.
Personally I feel 120km/h is a safe speed given good roads and conditions. All this being said, the most inventive way of controlling driver speed are sets of speed averaging cameras between locations—record the time when a driver enters a zone and when they exit, if they're managed to drive between the two locations in a time sufficiently greater than the set speed allows, issue ticket.
I don't like one off speed traps because it often causes drivers to slam on brakes and can cause traffic congestion, or worse, crashes, as drivers take their focus off the road and start staring at the speedo.
This is the same in most areas I have experience in the US.
Unfortunately here in the US using lower speed limits is an intentional form of revenue boosting for a municipality. Yes, the roads are safe enough to be driving 10-20 mph faster but if that were the speed limit they would not be making a profit.
The city of Boston found that lowering the speed limit by a a mere 5mph boosted ticket revenue by 47% and I am sure its common all over the nation.
Seattle is lowering speed limits to save lives. I don't believe the citation coffers are anymore full than before.
https://www.seattletimes.com/seattle-news/transportation/seattle-to-lower-speed-limits-amid-rising-number-of-traffic-deaths/
https://www.bbc.co.uk/programmes/b05pqskm
(Crossing Continents is a good radio programme and it's well worth a listen).
We know from Ferguson (and other places) that pressure is placed on police officer to raise revenue. https://www.bbc.co.uk/news/world-us-canada-31849421
Yeah I am talking exclusively about highways. Personally I’m a strong believer that with the transition to EV’s the environmental impacts of higher speeds will be increasingly mitigated.
And well... city centres? For the most part they shouldn’t have cars in them anyway at all.
The environmental impacts are not so clear to me, as a bicyclist and pedestrian, who frequently witnesses drivers already ignoring speed limits on two-lane highways.
Increased speed increases the chance of death. The propulsion method (EV or gasoline) makes no difference in the pedestrian lives taken by increased speeds.
Please, slow down.
Pedestrians and cyclists aren’t allowed on the roads I’m talking about in New Zealand.
And don’t worry, I’m a cyclist too. I know full well what it’s like to be on the receiving end of abuse from car drivers. There’s no need to turn this conversation into a flame war about transportation modes.
Don't worry, I'm a driver too. My comment did not prefer one transportation method over another.
Let me be clear - Increasing speeds because a vehicle no longer burns gasoline is sounds like a bad idea to me. My comment intended to make it very clear the environmental costs include more than carbon.
Best of luck promoting increased speed limits for EV Vehicles in New Zealand. Please considering elaborating on such a specific situation in a more upfront way in the future.
I have smattering of (probably easily counterable) thoughts and opinions:
None of your suggestions are bad. They do, however, require both highways and cars to be much more heavily filled with electronics.
The highway control systems would have to maintain constant contact with the weather surveillance systems. There would also have to be frequent tableaus telling the drivers of the current restrictions. Both cost electricity to run – quite a bit of electricity, if I'm correct about this.
The cars would have to have some form of proximity sensors built into them. I don't know with certainty, but any small piece of external electronics sounds like something that could break easily, meaning maintainance.
At this stage, I figure a Tesla-like auto-driver / driver-assistance system in conjunction with a country-wide wireless information system would be almost handier to build.
France has a low-tech version of this (the Reddit images link was the first on Google) where the speed limit is higher in good weather.
https://i.redd.it/vwiiufzw60i11.jpg
And we have electronic versions of this on I70 in the Colorado mountains as well. I've seen the speed limits set anywhere from 50-75 MPH on them depending on the day and weather.
The idea of dynamic speed limits has merit. Where I live the speed limit on the Interstate is 70 MPH, but in construction zones it's 50 MPH. However, it's only 50 MPH when the lights are flashing on the notification sign, and those lights only flash when people are actually there. Drivers slow down because people generally want to be safe and they know that when the lights are flashing there's a reason for it. Contrast this with some of the western states I've driven through where the speed limit on the interstate can be as high as 80 MPH and the construction zones are posted at 50 or even 55 MPH but nobody pays attention to it because often there isn't a dang thing going on and the construction zone is 10s of miles long. I think it's the dynamic and sensible approach that my current location uses that makes a difference.
If you want to control the speed of traffic, you need to build roads that start feeling unsafe when people are driving faster than you want them to go. On a wide, straight road, people will gun it. If the road is narrow and winding, people will slow down without needing speedbumps. Any form of external control will have limited compliance as compared to managing the limits within which they feel comfortable moving.
This is called traffic calming, and I’d argue that it’s the “correct” answer to OP’s question. It is the main technique employed by countries like the Netherlands, and it has been extremely effective—they consistently hover around the least traffic fatalities per capita worldwide.
The idea is simple and grounded in basic design principles: instead of telling people how to use a system, design the system such that users are implicitly guided to use it as intended and stay within acceptable limits.
Note that I said that it would start feeling unsafe. A trained driver would still be able to go faster, especially when other vehicles are pulling over to clear the way.
How many people would agree with roads that are more expensive to build and that comes with builtin speed control, meaning that the ONLY way to change the maximum speeds is by making additional expensive changes?
How often is anyone going to change the speed limits? We know what human reaction times are like and what counts as a safe speed for residential streets. Also, not all of these require massive physical changes. Things as simple as having narrower lanes striped on a multi-lane street causes people to drive slower.
IDK. A lot goes into those kinds of decisions, and not all factors are directly related to science or engineering.
Narrowing lanes is proven to reduce speeds as well as crashes.
There is lots of research and empirical evidence on this stuff.
This is an interesting angle - the feeling unsafe one. I wonder if you could pave roads in such a way that at some tire RPM they produce resonance in a way that feels uncomfortable? It obviously wouldn’t work for all wheel sizes, just spitballing really.
That's brilliant! In general, you have 2 options: punish people who go over the limit, or reward people who stay within the limit. Punishing doesn't work because there are too many people and the chances of getting caught are essentially nil. Also, the wealthier you are, the less the fine hurts, so it becomes another case of the rich buying their way out of following the rules.
As an example, I live in a neighborhood that's wedged between 2 major streets in Los Angeles. The 2 streets meet at one end of our neighborhood and move apart as you get to the other end. People really don't like going all the way down to the point and then turning from one to the other, so they prefer to go through our neighborhood, but there are posted signs saying they can't do that from 7AM to 9AM and 5PM to 7PM Monday through Friday or something like that. They do it anyway. Every month or two, the cops hang out just inside our neighborhood and ticket people who try to cut through. It stops the flow for literally 1 or 2 days, and then it starts again.
I'm surprised that rewarding people works, but then we still have regular lotteries, so I guess it follows that people can't do the math and will slow down thinking they'll win the lottery. Great!
For highways it would be easy to enforce an average speed between point A and B using the same cameras they use to collect tolls. But I don't think that's what most people care about.
This.
Average speed measuring has been so effective in some tunnels in Norway that the populist Progress party in Norway voted to limit the use for reasons.
You don't drive too fast if you get fined for doing so. You adhere to the speed limits, and that's not something their electorate wanted.
Immediately after the Progress party left government earlier this year, the Christian folk party, who got the transport ministry, said they'd reverse the Progress party stop of more average speed measurements. Because they work.
I guess the other question is, what is the purpose of slowing people down? Are we talking about in neighborhoods where there may be pedestrians? Or are we talking about on the freeway where it's mainly people driving long distances with the occasional on-ramp or off-ramp?
Human drivers tend to make an unacceptable amount of mistakes, and accidents at a higher speed tend to be more fatal.
Have you noticed how anybody who’s been driving for a while can automatically estimate the appropriate speed of a (previously unseen) road, as soon as they enter, without needing to look at the posted limits? Even more, they will dynamically adjust their speed based on that perception.
Using this instinct, I think that people naturally adjust their driving to maintain a constant level of difficulty (set by their emotions and processing ability at that time). Can you making somebody read slower, by posting speed limits (words per minute)? It’s biologically near-impossible.
Therefore, the most important trick to lower speeds is to not make the road “much easier” to drive on (divider, straight long wide lanes, etc), especially in residential zones — don’t make it feel like a free way! Instead of blindly getting carried away with forcing speed limits, it’s important to have a good mental model of human behavior and the mechanisms by which some intervention might (or might not) improve safety.
Unfortunately, this does nothing to uniformize the difficulty level that different people experience on a given road at a given time (eg: young but experienced drivers -vs- elderly drivers -vs- beginners).
Driver speed is largely a function of road design.
What it really boils down to is make drivers think they might cause damage to their cars and they will slow down. I'm not aware of anything else (other than directly seeing law enforcement) that works.
One of the interesting things about electric cars is how quickly they decrease in efficiency with increased speed. This is all more or less due to increased drag, but it causes a noticeable loss in range in speeds above 70 mph, at least in the Model 3.
For example, a Tesla Model 3 (2019 LR 18" w/ Aero caps) traveling at 55 mph will have a range of approximately 417 miles, well above its rated 325 mile EPA and advertised range (a 28% increase!). At 70 mph, this is close to 324 miles. 80 mph, 273 miles (16% decrease from the rated range, and only 65% of the 417 mile range).
I've noticed this has caused me to be more aware of my speed during trips and I've gone from cruising around 80 mph on the interstate (with a gas car) to limiting myself between 70 and 75 mph, speed of traffic dependent.
When I discovered this, it really made me wonder if when electric vehicles become dominant, if this effect would encourage lower speeds for higher efficiency.
This is true in every car in the same way, not just electric cars.
I don't know the exact numbers, but every car has an "optimal" speed that will give it the most range. Cars with more drag, for example, will have a lower optimal speed. For ICE (internal combustion engine) cars, it's usually around 45mph, because a good amount of fuel is needed just to spin the crankshaft and move the pistons. In electric cars, that's somewhere in the ballpark of 15-20mph, because there are no big efficiency losses anywhere in the system.
Doubling speed quadruples drag; this becomes a very big effect at high speed.
While true, I would argue most people don't seem to care about this when driving ICE vehicles and the vehicles themselves aren't as accurate in predicting their range as battery EVs.
This awareness will probably fade as better tech comes along, be it very fast charging times and ubiquitous number of charging stations, and/or greatly increased range of standard vehicles.
I'm hoping this is a problem that will be solved to some degree by self-driving fleets. Once there are enough of them on the road following the speed limit, it will be harder for human-driven cars to maneuver outside of them. Past a certain critical mass, people will almost always be "stuck" behind a computer-driven car that actually follows the rules and doesn't care about their emotions.
While this will possibly limit human drivers who go too fast, it's still at the mercy of human drivers who go too slow, though. There is little that annoys and frightens me on the road more than people who are so terrified of merging that they'll attempt it at half the speed limit, unintentionally endangering themselves and everyone around them. A modest proposal would be asymmetric cattle-pushers with aggressive algorithms to push drivers going too slow into the ditch...