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"Going Up" At 45 Mph: Hitachi To Deliver World's Fastest Elevator
Zothecula (1870348) writes "Hitachi has announced that it's installing the world's fastest ultra-high-speed elevators in the Guangzhou CTF Finance Centre skyscraper in Guangzhou, China. Making up two out of a total of 95 elevators in the building, Hitachi says the new lifts use a range of technologies to produce record-breaking speeds of 1,200 m/min while still meeting the necessary standards of safety and comfort."
I think it would be cool to go 45mph from one floor to the next, provided the elevator is well padded.
“He’s not deformed, he’s just drunk!”
High speed elevators are stupidly expensive.
I was looking at apartments a while back and at one of the buildings there was some ongoing construction.
Somehow I ended up getting shown around by one of the head contractors who told me that the building was supposed to have four medium speed elevators, but they got permission to knock it down to 3 high speed elevators, which would move the equivalent # of people per arbitrary unit of time.
The kicker was that those 3 elevators were about 1/4th the total budget of the entire building.
So based on that, I'm guessing that TFA's 95 elevators are a respectable portion of the price for that new tower in China.
[Fuck Beta]
o0t!
For a 3m floor height, I find about 27.5G, at least.
45mph => 20.12 m.s^-1
a t_m = 20.12 m.s^-1
a t_m^2 = (3m / 2) (max acceleration obtained at half the floor height).
=> a = 20.12^2 / (3 / 2) \approx 270 m.s^-2 / or 27.5 earth G (G = 9.8 m.s^-2)
Where the limit of the human body for such vertical acceleration seems to be between 2,3G and 5G, depending if you are going up or down... but I haven't tested that myself).
Ok, back to work now...
45mph doesn't actually sound very fast to me, especially going down.
I RTFA, and all it says is 440 meters in 43 seconds. I'd like to know the acceleration profile for this thing, it sounds like fun!
John
Some of these towers have an upper lobby. So you take the express from 1 to 75, then a 'local' from 76 to 100.
Usually the 'important people' are on the top floors so the elevator ratio is better and there's little waiting in the upper lobby. Unless you stop at the bar.
Once in a blue moon there's an express to the penthouse, but to pay for an entire express elevator entirely in the rent of the penthouse apartment isn't feasible for all but the ultra-ultra rich.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
learned this thanks to SimTower.
No, no. Total travel distance is 440m, so it's 220m to max speed of 20m/sec. Assuming constant acceleration (which in practice you don't do because the startup jerk is awful) V=a*t, and d=0.5a*t^2.
d=220m, V=20m/sec.
V/a=t, so d=0.5*a*(V/a)^2
d=0.5*V^2/a
a=0.5*V^2/d
a=0.5*(20m/sec)^2/220m
a=200/220=0.91m/sec^2
1 g = 9.8m/sec^2
a=0.092 G
So it's about a tenth of a g. Riders are going to notice that, but it's not overwhelming.
This is a simplistic analysis. You have to keep jerk (the third derivative) small. The acceleration has to be applied gradually, and reversed gradually half way up. So the peak acceleration is a bit higher than that.
and you were the only occupant
There's going to be lots of crying babies!
46137
What does the acceleration vs time graph for an elevator look like, before it's reached 'cruising' speed?
If the elevator accelerated at a constant rate, I found that its acceleration would only be ~1.99m/s^2 or 0.2g's. I used the fact that it travels 440 meters in 43 seconds and its cruising speed will be 20m/s (all taken from TFA). According to those numbers, it would accelerate for the first 21 seconds, cruise for 1 second, and then decelerate for the last 21 seconds.
I want my high speed elevator to descend at a rate *just* fast enough to have me hovering six inches off the floor, which should be made of glass.
Some trouble with the 'Reply To This' function, I see...
No, no. They were talking about going from one floor to the next, which would only be about 3 m. I'm pretty sure they were joking, though.
Nope, you're off by a factor of two, I'm afraid. It should have been:
1/2 a t^2 = 3/2
t being the acceleration time (half the trip time), a the acceleration while going up, 3/2 the total distance while accelerating (half the trip), and a*t = 20.12
That works out to: a = 135 m/s^2 = 13.75g.
Which would be 14.75g while accelerating up, and 12.75g while decelerating, since you get 1g from just standing still.
If you want the same experienced g-force for acceleration and deceleration, it would be:
1/2 v^2 / (a+g) + 1/2 v^2 / (a-g) = 3
which works out to a very slightly higher: a = 135,6 m/s^2
Of course this all assumes a very jerky immediate acceleration and deceleration, which might lead to complaints from passengers. What we really ought to do, is figure out how to do it with a third derivative that has a constant absolute value. The maximum acceleration will be a bit higher then.
go your ears!
And when someone hits the emergency stop or the power fails at full speed...
I see you are worried that the real engineers developing those things have to work with so called computer scientists and this can cause accelerating pedal problem like in Toyota? I think that is a fair question but I am sure this gets squeezed in next sprint so all will be well...
OK, with a bit of mathematica:
Accelerate with a "jerk" (derivative of acceleration) of 3620 m/s^3 for 0.07455 s to a top acceleration of 269.9 m/s^2, speed is 10.06 m/s at that time.
Keep accelerating, but with acceleration decreasing back to zero during the next 0.07455 s. Top speed is 20.12 m/s.
During the next 0.07455 s, deceleration increases from zero to 269.9 m/s^2, speed goes down to 10.06 m/s
During the last 0.07455 s, deceleration decreases to zero which is reached exactly as speed reaches zero.
Total time is 0.298 s, top acceleration is 269 m/s^2 which, if you take the 1 g from gravity into account, gives 28.5 g during the acceleration and 26.5 g during the deceleration.
If you want the maximum experienced g-force to be the same during acceleration and deceleration, you either have to reduce the derivative of the acceleration (so that it's not the same as that of the deceleration) or add a short time of constant acceleration between the first two phases. This would make the calculations slightly more complicated but frankly, I don't think the passengers will really notice so maybe it's not worth the bother.
Depends on who the other occupant is and how romantic you are about dying together.
This building is only 530m high. Even at a 30mph you could do that in about 20 seconds and thats assuming you're going all the way from the bottom to the top. For that distance this lift would save around a whole 5-6 seconds (not counting acceleration time). BFD.
Sounds like an expensive technology showcase rather than something that will be a major extra benefit.
I wonder how they avoid the popping. The article says that they use some kind of fancy pressurization system for that, but you still have to change altitude in a short amount of time, so how do you "avoid" that pressure change? You could pressurize the whole building, but then the windows couldn't open, you couldn't have a terrace (except if it had an ear-popping airlock), and there would be a constant strong draft from top to bottom unless you kept the floors sealed airtight (which is kind of hard to do if you have things like elevators)
I imagine the best they can do, is spread out the pressure change over the slightly longer period that includes the slower parts of the journey and the wait for the doors to open, but that won't make such a huge change.
All we need now is to speed up 3D printers, and we can have food synthesizers.
As if standards or regulations ever stopped a real sw developer ...
Each passanger would have to be packed in metal armature, alternatively plasma armature can be used but that can leave some burns on the passanger. There may be some problems with structural integrity of load (liquidification) which can be bypassed by shock freezing (Han Solo).
Clearly you have never experienced an elevator ride in China. In some cases I'm sure that if passengers were to synchronize their breathing the ones in front would be crushed to death.
Put as many Gs as you want on that elevator, people won't move unless you put a coat of K-Y on the walls, in which case they will move as a team.
lucm, indeed.
I'd like a really slow, large elevator containing a restaurant or a bar. Have dinner or get pissed on the way home! Perfect.
Deep freeze the load and all acceleration problems go away.
The problem with ascending or descending that fast is that many people will have issues with sinus pressure that can't keep equilibrium. Comfortable ascent/descent in an unpressurized airplane is between 500 fpm and 1000 fpm. 45mph straight up or down is about 4,000 fpm. It hurts my ears just thinking about riding this elevator without it being pressurized!
As long as it doesn't accelerate faster than ~9m/sec, your feet don't leave the ground.
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No time for love in an elevator.
Have gnu, will travel.
... must come down.
Tell that to the voyager probes.
Will this elevator provide foot locks such that people will not 'leave' the floor when it's descending at ~72kmph?
And how are they getting around the queasy sensation you'll most probably feel?
Also. I think you underestimate just how fast you need to accelerate to lave the ground. Lets just say it's more than 9 meters per second squared.
I'm a good cook. I'm a fantastic eater. - Steven Brust
True!
Still a bad-ass acceleration though...
I visited Taipei 101 a few months back, which has (IIRC) the fastest elevators in the world right now at about 35 MPH.
My ears popped three times. Each way.
So the answer is simple: they don't avoid the popping.
It doesn't hurt to be nice.
...dying *crushed* together.
FTFY
I've been in the elevator business for 30 years. One floor runs are not done at speeds of over about 250 FPM, depending on floor to floor distances.
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
This may be a anecdotal comment, so take it for what you will, but I have noticed that Asian buildings and infrastructure technology are so far ahead of us in the USA that it is really embarrassing if you go there and come back and compare.
If you've ever gone to Taipei 101 for example, the elevators move so quickly, and without any vibration as they go up/down that you almost cannot tell if they're moving. Go to Singapore or Hong Kong, and watch how smoothly, quietly, and punctually their subway systems run.
Or go to China and be surprised that in even small-sized cities, you didn't realize that *all* their motorcycles are now electric and they leap-frogged the smelly gasoline phase of motorbike technology.
You come back to the US, and wonder how we're still (maybe) #1, with our rickety buildings and public transport systems. It's embarrassing. And people will say, well, "Who needs quieter, smoother subways? What we have is fine." Said while yelling because you have to cover your ears to not go deaf on the F train in New York City. And as you have to hold your nose as you walk through the piss-soaked, dark and dingy subway/bus station concourses.
Sometimes I feel like we're witnessing the slow decline of American technology / investment when it comes to public infrastructure.
I'll stick with my Sirius Cybernetics Happy Vertical People Mover, thank you very much. It may be a bit unhinged, but damnit, it gets me where I need to go (well, when it's not sulking in the basement, anyway).
"The Baby Popper"
Wouldn't a falling elevator "box" have its own terminal velocity? Unless the shaft were air-free (e.g. vacuum).
I suppose the descent could be powered... that would work pretty well, at least once.