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Comment by alexland | Hacker News Reader

It's a temporary problem though. Speed limits are set to try and keep people safe, by enforcing a maximum speed. Once computers drive the cars, the speed limit can be cranked up because reaction time goes up drastically and distracted drivers are nonexistent. I expect to see lots of changes in driving laws once automation takes over for exactly this reason.

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"Once computers drive the cars, the speed limit can be cranked up because reaction time goes up drastically and distracted drivers are nonexistent."

That doesn't mesh with areas where robots have already taken over. The robots moving freight around shipping terminals don't move any faster than humans driving trucks. The robots I see delivering drugs in hospitals don't move faster than the nurses.

Speed limits aren't just about the cars. Noise and pedestrian safety are big factors. There is no technology yet that can allow a robot to see around blind corners. They may have a 1/4second faster reaction time, but that won't mean they could be trusted move much faster towards a crosswalk that might see a bike cross at any second.

The hospital robots seem like the closest analogue for now, as it's automation being held back by needing to coexist with inferior-performing humans. If it were only robots in the hallway, it'd likely go a lot faster, no? Just like if it were only computers driving the cars, following distances could be greatly reduced because they can react faster.

If it were only robots in the hallways, it wouldn't be a hospital. They did try giving the machines their own pathways. That's what pneumatic tubes were: a fast lane for robotic delivery. Frankly, for a hospital, pneumatic tubes would seem the far more elegant solution.

I guess it boils down to perspective. The hospital robot is in no hurry. His life is no better or worse if he is faster or slower. But a human inside a robot-driven car does care. He doesn't see the overall traffic efficiencies, and even if he did he wouldn't take much notice. All he cares about is getting to the destination asap. So it is a different speed decision than the robot.

The hospital I'm employed at utilizes both pneumatic tubes and robots. Robots roam the basement and employee only areas shuttling around food carts, linen carts, and trash. The pneumatic tube system reaches everywhere in the hospital and sends drugs, lab specimens, and basically anything else small enough to fit in the container.

I knew of a hospital when I was a kid that had raceways mounted just below the ceilings. It was like little toy trains bringing paperwork and drugs to each room. But if you watched them long enough, four-legged critters also used the raceways.

While the robot can't see round blind corners in the manner a person could, visually processing it, we could require aircraft style transponders on all road vehicles, which would then allow your robotic car approaching a blind corner to know of there's anyone on the other side. It would also allow unambiguous communication as to how fast each vehicle is travelling, and their intentions - think in terms of the brake and indicator lights also being part of the transponder signal.

So you want to fit all humans with radio transponders? That's going to be fun to enforce.

It's more likely to be cranked down though, because that's more efficient and people might be less frustrated with slow driving if they can kill time on their phones during the drive.

Kill time? Regardless of who is driving, time spend sitting the car is time spend away from family/pets/work/food/bathrooms and everything else important.

Don't worry, Tesla model S comes with a bathroom, a car office, a mini kitchen and a petting zoo

So Telsa is branching out into RVs? I guess that would be the logical synergy of telsa performance cars and tesla wall-mounted battery packs.

The improvements in traffic flow gained through full automation may even offset the decreased speed limits.

Or full automation might increase the number of vehicles and exacerbate the problem. (On the assumption that the vastly reduced cost of fielding driveless vehicles could result in many more commercial vehicles on the road.)

But automation can also increase vehicle density: "Stop and go" traffic is way more efficient when it's not groggy humans doing the stopping and going.

I'm not sure about that. Keeping the cars closer together would suggest more abrupt acceleration and braking to such to avoid space being created as the car ahead accelerates from a stop. Given these accelerations will not be initiated by the driver, they will come as a surprise and thus be more jarring. I imagine that might result in autodrives that accelerate/brake more slowly, leaving greater distances between cars in stop=and-go environs. And I cannot see autodrives leaving much less room between cars while in steady motion or stopped. Humans are pretty good at tailgating.

I think the key is that computer controlled vehicles could synchronize their stopping and starting. You wouldn't have to wait for the few feet moved by the car in front to bubble down the line as drivers notice the extra space. Instead, all stopped cars could coordinate to advance simultaneously.

You wouldn't even have to explicitly sync them; it'll take just few milliseconds for a self-driving car to notice another car is beginning to accelerate. Machines can keep precise control to the level simply unavailable to and unperceivable by humans.

At least in theory with proper communication channels between vehicles, vehicles could alter their speed just enough to make space for merging traffic or to allow a vehicle to turn. In that way nobody ever actually stops or starts, they just become slightly slower or slightly quicker, which should be much less jarring.

s/kill time/do something useful/, like reading books, working, having fun, sleeping. Time spent driving where a "self-driving" alternative is available is absolutely wasted.

That won't work for all the people who'll suffer car sickness when they spend time focusing on their phone while in a vehicle. Intermittent messaging is OK for most people but have you tried reading a book as a passenger? We might find that most people have to look out the windows so often that they can't get much productive work done.

I used to have car sickness as a kid. I recall some of it being caused by vibrations made by the engine. The smell of gasoline was also vomit-inducing for me. Both of those issues are solved by electric cars.

> Speed limits are set to try and keep people safe, by enforcing a maximum speed.

That's one reason. Then there's the money printing aspect of it and the environmental aspect of it.

Don't forget the occasional "keeping cyclists and pedestrians alive" aspect.

I thought that was covered by 'keep people safe'.

Some problems are less temporary. The required energy over distance goes up as well, thus limiting your action radius. Furthermore, the amount of road noise produced rises as well, which is another important limiting factor in high-density areas.

I doubt if the speed will increase in 25 mph residential areas.

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