Engineers Develop 'Ultrarope' For World's Highest Elevator

HughPickens.com writes: Halfway up the Shard, London's tallest skyscraper, you are asked to step out of the elevator at the transfer floor, or "sky lobby," a necessary inconvenience in order to reach the upper half of the building, and a symptom of the limits of elevators today. To ascend a mile-high (1.6km) tower using the same technology could necessitate changing elevators as many as 10 times. Elevators traveling distances of more than 500m [1,640 ft] have not been feasible because the weight of the steel cables themselves becomes so great. Now, after nine years of rigorous testing, Kone has released Ultrarope — a material composed of carbon-fiber covered in a friction-proof coating that weighs a seventh of the steel cables, making elevators of up to 1km (0.6 miles) in height feasible to build.

Kone's creation was chosen to be installed in what's destined to become the world's tallest building, the Kingdom Tower in Jeddah, Saudi Arabia. When completed in 2020, the tower will stand a full kilometer in height, and will boast the world's tallest elevator at 660m (2,165ft). A 1km-tall tower may seem staggering, but is this the build-able limit? Most probably not, according to Dr. Sang Dae Kim. "With Kingdom Tower we now have a design that reaches around 1 km in height. Later on, someone will push for 1 mile, and then 2 km," says Kim. He adds that, technically speaking, 2 km might be possible at the current time. Anything higher would require new materials and building techniques.

Comments

just put a motor on the elevator itself

[Noah Haders]

i would do away with the motor at the top of the shaft, and instead electrify each individual elevator so it has motive power. seems like the best solution to me.

Re: just put a motor on the elevator itself

[Anonymous Coward]

With a magical lightweight power cord, perhaps?

Re:just put a motor on the elevator itself

[Anonymous Coward]

I think the concern there would be safety, since there is no cable to arrest a fall.

Re: just put a motor on the elevator itself

[Anonymous Coward]

Ruby on or off the Rails?

Re: just put a motor on the elevator itself

[Anonymous Coward]

And before you get all "vertical rails?!" indignant:
http://www.cograilway.com/images/Rack_and_pinion_animation.gif

Re:just put a motor on the elevator itself

[BarbaraHudson]

The cable doesn't arrest the fall - brakes do.

Re: just put a motor on the elevator itself

[dabridgham]

Or induction rails up the sides of the elevator shaft.

Re:just put a motor on the elevator itself

[Anonymous Coward]

Cables don't arrest falls today. There are safety rails that the elevator wheels brake onto. They exist to arrest falls cause the cable snapped.

Re:just put a motor on the elevator itself

[Anonymous Coward]

You still need a counterweight or else you are lifting the entire mass of the elevator instead of just passengers. That means a cable.

Re:just put a motor on the elevator itself

[Anonymous Coward]

The tension on the cables inhibits the brake.

Re: just put a motor on the elevator itself

[pavon]

No, you could use a conductive rail, like a subway, and rack and pinion system to move the elevator. The rack and rail would add a fair bit more total weight to the building compared to a cable. But more importantly, the motors would have to be much much more powerful! Modern elevator systems have a counter-weight balanced on the other side of that cable, which means the motor only has to overcome friction and the small difference in weight between the elevator and counterweight (which varies depending on current payload). The motor on an elevator like Noah is suggesting would have to provide enough force to counteract the entire weight of the elevator + payload + motor + friction, which is at least an order of magnitude more than a traditional elevator.

Re: just put a motor on the elevator itself

[Arthur B.]

Add in a battery or a flywheel and recover the energy on the way down.

Re: just put a motor on the elevator itself

[Anonymous Coward]

Calling out a person for behavior you present is not going to change anything.

The main problem with rails is that you need a sliding contact. That means arcing at the contact when the air gaps are eventually going to occur (nothing is 100% flat, and air pockets will eventually get between the contact and the brush). Arcing isn't going to cause immediate failure; but, it will leave a carbon / oxidation residue at the arc site. This means that future electricity will have to flow through a very small scale resistor, generating heat. Eventually the heat will cause pitting, accelerating failure.

This is why most in-wall electrical sockets are designed to scrape the plug slightly on insertion. It is a self-cleaning feature of electrical wall sockets, and any wall socket that doesn't provide some modicum of resistance when inserting a plug should be replaced as soon as possible. A loose wall socket will not clean the prongs on the plug, carbon will build up within the socket, and the heat will eventually lead to arcing that will melt the plug, the socket, or both (possibly starting a fire as a side effect).

The issues of contacts on long electrical rails can be fixed by turning the rails into flexible cables; but, that only recreates the cable problem. Even though an electrical cable could be theoretically lighter than the lift cable, it still has to lift its own weight, and an under-built electrical cable cannot entertain even micro-fractures in electrical conductivity without have an accelerated repair cycle.

Now you know why virtually all elevators use cables for lifting with a fixed motor.

Re: just put a motor on the elevator itself

[turbidostato]

"Add in a battery or a flywheel and recover the energy on the way down."

Batteries and engines weight. A lot. You don't want them atop a high building.

Re: just put a motor on the elevator itself

[jklovanc]

If sliding contacts are such an issue then how do electric trains overcome it?

Re: just put a motor on the elevator itself

[ShanghaiBill]

With a magical lightweight power cord, perhaps?

The British already have a twenty mile long extension cord that they use to power the trains going through the Channel Tunnel. They reel it out as each train goes through, and then wind it up afterwards to prepare for the next train. There is no other way to do it, since it is totally impossible to transfer electricity to a moving object through, say, a power rail.

Re: just put a motor on the elevator itself

[Anonymous Coward]

So don't put them atop the building. Or on the elevator. There's no reason the energy storage medium can't sit at the base of the tower; after all, sending electrons up/down the shaft is comparatively trivial.

Re:just put a motor on the elevator itself

[ihtoit]

you can build as high as you want as long as you can build a cable long enough to service the elevator. Cable length isn't a problem, the weight of the cable is. In systems such as this very simplified model of a counterweighted elevator http://s.hswstatic.com/gif/bt4... it's assumed that the rope weighs nothing, therefore the counterweight only needs to weigh 25lb - even taking into account the rope's weight, all other things being equal it balances itself. That's handy, scaling up you only need a 400lb counterweight for a lift rated at MGW: 1600lb (ten persons (800lb) + 800lb car). This arrangement does of course necessitate four times the length of cable as the height of the shaft, and with another shaft-length you can actually mount the motor at the bottom, negating the requirement for a counterweight - the motor only has to overcome the weight of the car through the system, which practically means it's pulling against a quarter of it. For some reason that's not really practical, so in this arrangement you'd have a counterweight one side, top-anchor the other end of the rope and have the motor roll the cable somewhere in between. FWIW when you see an elevator car with four cables, you're not seeing four cables, it's one cable. It's this arrangement of three (strictly, four, but the car pulley can be and often is a twin) pulleys, a counterweight and a top anchor. Other setups have the anchor point actually on the roof of the car, still others have the car and the counterweight on their own bottom pulleys, both ends top-anchored and the motor in the middle sharing rope between essentially two double systems.

(grew up in a tower where the elevator spent more time stuck between floors than enough, often with me trapped in it. Hearing firefighters clambering around up there to attach car batteries to the brake solenoids so they can lower the car to the ground after eight hours is a terrifying thing for a four year old. Nerd points for spotting the ropes and asking about them when they were fixing the thing, though).

Re:just put a motor on the elevator itself

[Anonymous Coward]

the tension on my bullshit-detector inhibits my belief in your post's veracity

Re:just put a motor on the elevator itself

[ganjadude]

Vertical maglev? Why hasnt anyone done that before? Wouldnt be hard to make safe either, in case of power loss, hace a locking system on each floor or each foot or something.

Re:just put a motor on the elevator itself

[Aardpig]

And how do you handle the counterweight? What's that? You don't actually understand how an elevator works?

Re: just put a motor on the elevator itself

[Anonymous Coward]

Noticed that ozone smell when you run your trainset ?

Re:just put a motor on the elevator itself

[Noah Haders]

you wouldn't need a counter weight cuz of the motors in the elevator itself. got questions? yo I'll solve it.

Re:just put a motor on the elevator itself

[Hadlock]

With today's ultra capacitors it seems like you could recapture 70% of the energy on the way down again. Maybe more.

Re:just put a motor on the elevator itself

[Jeremi]

And how do you handle the counterweight? What's that? You don't actually understand how an elevator works?

If your electric motor is powerful enough, you can dispense with the counterweight. It might not be very efficient, but it's possible.

Re:just put a motor on the elevator itself

[germansausage]

He has it exactly right. The tension on the cable pulls on the elevator brake to release them. If there is no tension on the cable, ie pulley or cable fails, the cable looses tension and the brakes apply.

Re: just put a motor on the elevator itself

[arth1]

The motor on an elevator like Noah is suggesting would have to provide enough force to counteract the entire weight of the elevator + payload + motor + friction, which is at least an order of magnitude more than a traditional elevator.

Not necessarily, no. Put fixed motors on the shaft walls, not in the elevator, and put pinions on the outside walls or corners of the elevator. The only extra weight would be of the elevator itself, less the weight of the hanging cable which elevators today have to move, and less the weight of the braking system, which would now be in the building, not the elevator.
And the much smaller building mounted motors can recuperate some of the energy whenever the elevator is descending.
Because each motor would only have to lift the elevator for a small distance before the next motor takes over, I imagine that higher speeds can also be attained, with less energy expenditure.

Re:just put a motor on the elevator itself

[germansausage]

Why do you suppose they generally never do that?

Re:just put a motor on the elevator itself

[Anonymous Coward]

That's certainly an issue, but there's a bigger issue involved. You can only use 1 elevator car per elevator shaft. So, if you have a relatively short building you can just get away with having 1 elevator. However, for taller buildings a single elevator just doesn't hold enough people or travel fast enough to keep up with demand.

I used to work int one of the local high rises and they had an express elevator that went from the lobby to the 40th floor. And they had a set of local elevators that would handle roughly 20 floors each. Specifically because you could easily wind up with people being effectively stuck where they were if the cars were busy going between different floors.

That building was only a bit over 70 floors high. If you tried to have the elevators servicing the entire building, you'd have to have about 40 elevator shafts and even then it would probably be less efficient.

Re: just put a motor on the elevator itself

[fustakrakich]

Maybe we should apply this great cable technology to subway trains. I do notice the pits on the third rail. They always have to send some poor guy out to sand them out real quick before the next train comes.

Re:just put a motor on the elevator itself

[Anonymous Coward]

Perhaps you should read on how the Original Otis Elevator Break works

I'm not any of the above ACs; but, I assumed this was common knowledge of any ten year old. After all, if there wasn't a safety mechanisim, the car would fall to one's death above two stories. LD 50 for falls on concrete is somewhere between 10 and 15 feet (depending on study). Yes, there are survivors above 20 feet, but the odds are not in one's favor.

I asked my dad why all the elevators had "OTIS" printed on the threshold, and he told me about a famous elevator fall in New York City, which prompted Otis to demonstrate his "safety elevator" which had a tension arrested brake held open by the lifting cable. So apparently it is common knowledge, at least in the people who bother to learn.

Re:just put a motor on the elevator itself

[inasity_rules]

I have been down a 2km mineshaft(the shaft is deeper, but they only go down in +/-2km sections) in a 'cage'. There is no counterweight, but the AC winder that drops (yes, 'drops' is the right word) you and hauls you back out is pretty powerful. They account for cable weight and extension because there are rails in the cages and they need precision to match them up. They get about +/- 1cm. Operator skill is important..

Yes. It is possible even with old style cables, but to get anywhere in a reasonable time, you have to go bloody fast, and it is honestly really scary. It took us about 5 minutes to reach the bottom most of that time was slowing down. I don't recommend it for the the general public. Many shorter elevators are a far better idea. Can you imagine stopping at every floor for 1km?

Re: just put a motor on the elevator itself

[Anonymous Coward]

Why are you talking about wall sockets?

Linear induction motors.

Re:just put a motor on the elevator itself

[Anonymous Coward]

I asked my dad why all the elevators had "OTIS" printed on the threshold, and he told me about a famous elevator fall in New York City, which prompted Otis to demonstrate his "safety elevator" which had a tension arrested brake held open by the lifting cable. So apparently it is common knowledge, at least in the people who bother to learn.

Cool story, your Dad was probably either misinformed or pulling your leg. The reason that many elevators had "OTIS" printed on the threshold is because that is the marque of the company that built that particular elevator.

Re: just put a motor on the elevator itself

[Anonymous Coward]

It is managed by having the train move the solid rail, which contains scrubbers prior to contact to keep the line as clean as can be expected. However pitting still occurs on the rail, which is why they are designed to be easily replaceable. A building length vertical rail where the brushes follow the car would not be easy to replace, repair, or maintain.

Re: just put a motor on the elevator itself

[Anonymous Coward]

Train rails are excessively thick. This coupled with scrubbers around the brushes means that the rail is cleaned prior to contact, and the wear of the (cleaner) rail is minimized. This coupled with the minimal movement of a ground fixed tie and a very large amount of metal to wear through leaves the effective life of the rail in the +10 year range (if not +50 year range).

A building will have few of these advantages. Buildings in the 30+ story range sway. Excessively thick rails get far more expensive to run vertically, so the rail thickness will be minimized. This increases the chance of flex and decreases the amount of rail to wear out by scrubbing or pitting. It isn't that it can't be done, it's just that it can't be done easily, which translates to cheaply.

Re: just put a motor on the elevator itself

[fahrbot-bot]

With a magical lightweight power cord, perhaps?

Power it using lasers - duh.

Re: just put a motor on the elevator itself

[Billly Gates]

The real question.

First how do you get it up there? Stairs perhaps?

Re: just put a motor on the elevator itself

[Anonymous Coward]

Induction incurs a lot of losses. Yes, it can travel a small air gap easily; however, it does so with a lot of compromises. Some of the main challenges is heat generation and low power transmission efficiency. Increasing the power can attempt to address the latter but only at a cost of more heat. Also, induction has extra challenges when considering a moving receiver, and if you decide to address these by moving the transmitter, you then have a lift problem to solve for your transmitter.

I'm not saying that it is impossible, but it is far, far cheaper and more reliable at this time to not attempt to use inductive charging on a self-powered elevator.

And keep in mind that we are blessed with elevator brakes that are actively held open. A self-powered electrical elevator car would have a pretty high constant draw to replicate the braking system, as it would have to pull solenoids against the breaking springs.

Finally, current elevators don't lift the car. It is counter balanced with a set of stacked weights. The elevator motor (a fixed mounted motor pulling the cables) only needs to lift the difference between the two weights of the loaded car and the counterbalance weight stack. A fully self-powered car of the kind we are considering would not have a counter balance (because it would lack the connecting cable) and therefore would need even more power to lift the entire mass of the car.

That's a large increase of needed power coupled with a large decrease in power delivery. It is far from a trivial engineering problem to solve, and is unlikely to be solved favorable within our lifetime.

Re: just put a motor on the elevator itself

[Anonymous Coward]

You can transport energy via air there dies not need to be physical contact. But we don't need the engine to be on elevator. Instead the walls could push the elevator up and down like gut muscles push food. Or we could use fluids to push elevator up (does not scale well). Or we could have cables that attach and detach in the middle. There are many ways to solve this problem.

Re: just put a motor on the elevator itself

[fustakrakich]

Moderators please! I appreciate the props but nothing I said there was true!

Re: just put a motor on the elevator itself

[Anonymous Coward]

The power rail is supported every couple of feet by supports and a gravel bed. It's abrasion resistance is not a driving consideration in the razor thin safety factors preventing an apocalyptic scale game of "crack the whip".

When the 3rd rail's resistance at 600-1000Vdc causes it to get warm: the sky hook doesn't land on anyone's head as a result of thermal expansion and wind induced harmonic oscillation.

You should ask the engineers working on the space elevator what percent of the cable's diameter can be consumed by electro discharge machining before the safety factor is 1.0. Then you can ask those engineers what the allowable wear per round trip can be created by the carbon brushes before the entire rope has to be replaced and the cost of replacement per trip is more expensive than rockets(brushes are the primary consumable only because the weight penalty of a shrinking 3rd rail doesn't matter to anyone when it's supported every few feat by 4x4 wood/concrete supports).

I don't know these answers, but as an engineer: I'm confident the people who are working on this have already done this sort of economic analysis before making decisions. As an engineer, I also don't presume to tell IT professionals to use "Docker" for their server administration, or tell them they should use "Boost" library for their string handling.

I respect IT enough to where: although I am studying for my CCNA and have taken a few C++ and Java classes, I don't pretend to know better than your average professional just because I watched a show on Data Centers on the History Channel.

Re:just put a motor on the elevator itself

[Anonymous Coward]

I asked my dad why all the elevators had "OTIS" printed on the threshold, and he told me about a famous elevator fall in New York City, which prompted Otis to demonstrate his "safety elevator" which had a tension arrested brake held open by the lifting cable. So apparently it is common knowledge, at least in the people who bother to learn.

Cool story, your Dad was probably either misinformed or pulling your leg. The reason that many elevators had "OTIS" printed on the threshold is because that is the marque of the company that built that particular elevator.

Yes, you are right, it is because that is the marque of the company that build that particular elevator, which gained it's reuptation by inventing the first effective elevator breaking system .

My dad was occasionally misinformed, but there were a few famous (at the time) elevator plummets in New York City that nearly doomed the elevator to not gaining acceptance back in the late 1800's. Otis did a lot of advertisement of it's (at the time) revolutionary breaking system, which was deemed fail-proof, as failure meant the elevator would be immobile, the breaks being held open by the (signal) tension on the cable.

Today there are still similar designs at amusement parks and industrial floors. They are called dead man's switches. If an operator should die, he will fall off the switch which must be held closed for the machine to operate. It is a positive feed-forward signal meant to ensure that the machine only works when an operator is correctly operating it. Most have guards over the switch to further prevent disabling them with a heavy brick. Motor boats have similar features. A blade style run switch is kept open by inserting a metal contact attached to a lanyard meant to be attached to the operator's wrist. When the operator inadvertently gets knocked overboard (or at least out of his seat) the boat engine dies.

Otis was certain to exploit their patent by advertising it to absurdity. That's why their marquee is on the elevator threshold, so you would know it was an Otis, and that it had the (at that time) state of the art breaking system.

You did say probably, but next time, do a bit of research and eliminate the probability. Also, don't get too skeptical with other's knowledge about a subject you can't bother yourself to verify / disprove.

Re:just put a motor on the elevator itself

[Dutch Gun]

All the engineers who actually have to build these devices obviously never had the brilliant flash of insight after a few minutes of thought that our intrepid slashdot armchair engineers had, of course!

Re: just put a motor on the elevator itself

[Anonymous Coward]

Here's a hint. See those little metal bars that slide along the rails. They are (typically) pantographs. They are designed to wear out first, so the cables are spared. They are also easily (at least compared to the cables) replaceable, and there's an entire industry for detecting (in various ways) pantograph wear.

Re:just put a motor on the elevator itself

[Anonymous Coward]

Already done by the same compan, "Machine Room-Less Elevator".

Re: just put a motor on the elevator itself

[Neil Boekend]

Induction drives are not safe enough.
This is a design using a worm drive.
If you have exprience with worm drives you know their self breaking properties make this very safe. In addition the designs I saw years back had emergency breaking systems similar to normal elevators.

Re:just put a motor on the elevator itself

[bloodhawk]

yes, but the cable is only used as a triggering mechanism, used as it is obviously there and is simple. There is nothing stopping that triggering mechanism being anything from an acceleration fired mechanism, or pressure held open by the motors when they have power or any number of other methods.

Re: just put a motor on the elevator itself

[unrtst]

And keep in mind that we are blessed with elevator brakes that are actively held open. A self-powered electrical elevator car would have a pretty high constant draw to replicate the braking system, as it would have to pull solenoids against the breaking springs.

Use just a little more creativity. One possibility: Have brakes that are actively held open; hold them open with a quick release mechanism; for the quick release, hold its release via the constant power. If power is cut, it'll trigger the quick release, which will release the stored energy in the springs. It doesn't take much to hold back lots of stored power. Batteries and capacitors could also be employed at various points. Basically, this isn't a problem.

Finally, current elevators don't lift the car. It is counter balanced with a set of stacked weights.

At the proposed scale, 1km, I'm betting all that cable is placing a much higher stress on the system than the minor issue of having to actually lift the car (in addition to its contents).

I'm not claiming it's super easy, or that it'd even be feasible, but it sure seems like having 1km of cable is pretty ridiculous.

Re:just put a motor on the elevator itself

[ihtoit]

I saw a programme that dealt with this a while ago, it was using the WTC Twin Towers as a use case in splitting elevator loads and why the decision was made to stagger the system rather than have shafts that went from the basement to the roof. It wasn't a question of cabling, it was a question of how many full-height shafts can you cram into a building and stil have a habitable space?

Re: just put a motor on the elevator itself

[houghi]

The main problem with rails is that you need a sliding contact.

You could use a wheel. As you will need at least three wheels and most likely more to hold the cage stable, each wheel could be a contact point and each rail could be a slider.
Just look at any roller coaster and imagine the rails carrying the current and the wheels being the contact.

And even the slider has been resolved. Just look at trains.

The reason elevators use cables is because of the counterweight. That means less weight and thus less powerfull motors and thus cheaper.

However if the cable becomes heavier then the counterweight, it could become doable to use an on board electrical motor. The distance of 1 KM is nothing when you compare it to the distances metros, trams and trains travel each day.

Re: just put a motor on the elevator itself

[serviscope_minor]

Nope: there still needs to be a sliding contact between the wheel and a fixed cable somewhere.

Anyway, sliding contacts work just fine. See, e.g. trains with 3rd rail, 4th rail, pantograph and mixed mode trains and trolley busses and even some whacky covered contact trams.

The latter are particularly interesting. Some cities want an electric tram installed but don't want to have overhead cables or exposed foot level contacts. So, there are studs in the ground and they only switch on after the tram has made contact. The old systems were unreliable, but with modern arc-free power semiconductors, they work well and no arcing.

Re: just put a motor on the elevator itself

[Neil Boekend]

The batteries do not have to be on the elevator. They can be on the building side of the high powered rail. For example in the basement.

Re:just put a motor on the elevator itself

[gl4ss]

slower speeds, more noise, more danger, I would imagine.

btw KONE means MACHINE.

Re: just put a motor on the elevator itself

[Anonymous Coward]

Boost is garbage.

Like systemd.

And women's rights.

Re: just put a motor on the elevator itself

[rizole]

This is rediculous...British ingenuity did away with the mile long extension cord years ago. We now have a cordless extension cord to do the job.

Re: just put a motor on the elevator itself

[JonathanR]

If I were in the elevator, I'd rather it didn't break at all.

Re:just put a motor on the elevator itself

[Anonymous Coward]

Another advantage of the cable is that you can have a counterweight.

Re:just put a motor on the elevator itself

[LaLLi]

Queue the turbolift system from Star Trek http://www.theverge.com/2014/1...

Re:just put a motor on the elevator itself

[Anonymous Coward]

i would do away with the motor at the top of the shaft, and instead electrify each individual elevator so it has motive power. seems like the best solution to me.

There are elevators where the motor is attached to the car. Most of them have cables for the simple reason that it is practically impossible to make an elevator that is fast, has a smooth ride and doesn't have a cable. This is because it is lot more difficult to get the car move fast if it has to grab to the walls of the shaft or to some rails going in. If the shaft is a kilometer tall, you want to have lots of speed, and you need a cable for that.

Re: just put a motor on the elevator itself

[David_W]

Helicoper.

Re: just put a motor on the elevator itself

[David_W]

Er, helicopter. I just woke up. :P

Re:just put a motor on the elevator itself

[Anonymous Coward]

Actually an acceleration fired mechanism has an issue, it is a positive signal leads to braking system. An ideal system is a loss of a continuous signal leads to breaking.

It could be easily handled by having breaks held open by an electromagnet, with a spring attempting to close them constantly. However, that would require more power in the car, which would already be at a premium as now the car must be self-lifting instead of counterbalanced.

You want the braking system to fail closed, because there is a chance that the braking system itself will fail unrelated to car acceleration. If it fails when the car is not dropping, it is an inconvenience with a hold-open design. If it fails with a hold-closed design, you don't discover the failure until the brakes are needed.

An accelerometer also will be much harder to handle as a clean signal; because, the elevator is supposed to accelerate and deaccelerate. So with a system like you described, you need to calibrate the accelerometer and subtract from the output signal the portion being mixed in by the motor action. It might not be so easy to immediately identify controlled descent from uncontrolled descent without a sufficient drop. If that drop is higher than four feet, most passengers will be injured, as we don't pre-brace for impact in elevators due to their excellent safety track records.

Re: just put a motor on the elevator itself

[Anonymous Coward]

Just do it with a straight line lock and pawl system and have stationary bicycles inside the elevator that people must get on and pedal (with appropriate gearing; elevators are heavy) to cause the elevator to rise. Serves them right for taking the elevator the lazy asses; they should have used the stairs...

Re: just put a motor on the elevator itself

[mrchaotica]

Induction incurs a lot of losses. Yes, it can travel a small air gap easily; however, it does so with a lot of compromises. Some of the main challenges is heat generation and low power transmission efficiency. Increasing the power can attempt to address the latter but only at a cost of more heat.

With a km-high vertical shaft, I've got to think some use can be found for that heat (e.g. by putting an electric turbine at the top).

Finally, current elevators don't lift the car. It is counter balanced with a set of stacked weights. The elevator motor (a fixed mounted motor pulling the cables) only needs to lift the difference between the two weights of the loaded car and the counterbalance weight stack. A fully self-powered car of the kind we are considering would not have a counter balance (because it would lack the connecting cable) and therefore would need even more power to lift the entire mass of the car.

As somebody mentioned upthread, this is only true when the weight of the cable is negligible. If the cable weighs as much as the car, as it would in a sufficiently-high tower, then there are situations where the motor has to lift that much weight.

Re: just put a motor on the elevator itself

[Half-pint HAL]

Use just a little more creativity. One possibility: Have brakes that are actively held open; hold them open with a quick release mechanism; for the quick release, hold its release via the constant power. If power is cut, it'll trigger the quick release, which will release the stored energy in the springs. It doesn't take much to hold back lots of stored power. Batteries and capacitors could also be employed at various points. Basically, this isn't a problem.

The current system is very simple, and very reliable. The car is suspended from the cable via the brake. The tension generated by the weight of the car disengages the brake (because even when going down, the car still accelerates at less than the rate of gravitational acceleration. If the cable fails, the tension vanishes instantly, and the brake is engaged. This mechanism works instantly, even if the car is at rest when the cable breaks. Your suggestion works when the mode of failure is power loss, but in a self-powered electric lift, the loss of power would be less of an issue than loss of traction. The safety mechanism would only be able to detect loss of traction when the car is in motion, which means losing vital seconds as the elevator gains momentum, and therefore will result in needing a more powerful brake. And that means adding in more powerful, heavier systems to hold the break open, as opposed to the current system which just uses the weight the elevator already has. So now you're shifting more bulk again.

And all that for what? To create a lift that is far, far less efficient than the current model, because as the GP AC said, elevators use counterbalancing weights so that the only work they're doing is in moving the contents of the elevator -- the lift car and the counterweights practically move themselves.

Re: just put a motor on the elevator itself

[cornjones]

why would you make it building length? Have a series of them...

Re: just put a motor on the elevator itself

[Half-pint HAL]

Elevator brakes are one of the most elegant solutions known to man, and perhaps more crucial to the continued popularity of the cabled elevator. The brake is held open by spring tension generated by the interaction of the elevator and the cable. If the cable gets cut, the brake engages. That's it. Any other type of elevator would need a more complicated break system. Detection of fault conditions would be a separate action that triggers the brakes. That means delays, and the possibility of errors. It is practically impossible for a properly built cable elevator to plummet. You cannot say the same for any cableless concept design. One of the simplest ideas in legal liability is that if you opt to do something the more dangerous way, you're liable. You must have very good grounds to justify the risk.

Re:just put a motor on the elevator itself

[Half-pint HAL]

yes, but the cable is only used as a triggering mechanism, used as it is obviously there and is simple. There is nothing stopping that triggering mechanism being anything from an acceleration fired mechanism, or pressure held open by the motors when they have power or any number of other methods.

The beauty of the current brake is that it engages immediately on failure, regardless of what the elevator is doing at the time. If the cable breaks, the car stops. If you rely on an acceleration fired mechanism, the car will have to start falling before the system knows to shut down, and that could lead to serious injury. Power failure is also only one failure mode -- the next issue is loss of traction. The current system has one mode of failure and a brake that is physically bound to it. There is no safety mechanism comparable.

Re: just put a motor on the elevator itself

[Anonymous Coward]

Just use a fixed laser at the top of the well and a photon to electron converter on the elevator roof.

Re: just put a motor on the elevator itself

[bluefoxlucid]

Elevators already have phone and electricity to their control panels.

Re: just put a motor on the elevator itself

[bluefoxlucid]

Yeah that's not going to be 100%.

Re:just put a motor on the elevator itself

[Anonymous Coward]

I suggest we combine the two ideas. A tension cable that _helps_ with lifting, but by no means the primary lifter. Electric moters/rail gun power for the lifting. If there's a failure of ANY kind, the car drops, cable stretches/breaks immediately and *voila* brakes.

Re:just put a motor on the elevator itself

[Causemos]

Was a story about that last month.

Maglev Elevators Will Take You Up, Down, and Sideways by 2016
http://spectrum.ieee.org/tech-...

Re:just put a motor on the elevator itself

[dj245]

i would do away with the motor at the top of the shaft, and instead electrify each individual elevator so it has motive power. seems like the best solution to me.

The only benefit to doing this is to eliminate the cable. That leaves you with rack and pinion drive as basically the only realistic* option for moving the car up and down. Rack and pinion elevator cars are slower, noisier, and have substantially more vibration than hydraulic or cable elevator cars.

*Another option is a pneumatic elevator, but those are even slower and less suited for tall buildings.

Re: just put a motor on the elevator itself

[dj245]

No, you could use a conductive rail, like a subway, and rack and pinion system to move the elevator. The rack and rail would add a fair bit more total weight to the building compared to a cable. But more importantly, the motors would have to be much much more powerful! Modern elevator systems have a counter-weight balanced on the other side of that cable, which means the motor only has to overcome friction and the small difference in weight between the elevator and counterweight (which varies depending on current payload). The motor on an elevator like Noah is suggesting would have to provide enough force to counteract the entire weight of the elevator + payload + motor + friction, which is at least an order of magnitude more than a traditional elevator.

Let's not forget that rack and pinion elevator cars are significantly noisier, slower, and have much more vibration compared to traditional cable or hydraulic elevators. Rack and pinion is great for portable elevators but a poor choice for a short building, and an awful choice for a tall building.

Re:just put a motor on the elevator itself

[Anonymous Coward]

That still wouldn't fix the problem, not even close. The weight of the cable makes the cable in the middle break, or break at the connection points. The cable itself is no longer strong enough to hold itself, let alone that of the car or passengers when it gets to a certain length. Not to mention the safety factors that have to be built into the entire system. I don't know elevators for sure, but on permanently installed, powered scaffolding system which still put human lives at risk, have a safety factor of 10:1. Meaning if the system is designed to be able to lift 1000 pounds, it must be capable of holding 10,000 pounds. I don't know if that same safety factor is used for elevators or if it's lower, but since it's a permanent installation and uses essentially the same technology, I'm assuming it would need to have a safety factor similar to powered scaffolding systems. So when you have an elevator capable of having 3000 pounds of people in it, the cable and the rest of the system must be capable of holding 30,000 pounds. So what happens when your cable gets close to that weight alone?

Now, what about maglev elevators?

Here is an experiment you can do yourself. Take a plain garden hose, cut a 2" piece off, how easy is that to bend? Now take a 10' piece, it bends easily, now take a 3,000' piece (ok you can't do that yourself) and hang it from a building, watch it stretch and probably break under it's own weight.

Re:just put a motor on the elevator itself

[Anonymous Coward]

The mechanical losses are too high, even if we had perfect regenerative braking.

Re: just put a motor on the elevator itself

[nuckfuts]

An electric motor could act as a generator on the way down, reclaiming enegry that was spent going up. Not with 100% efficiency, obviously, but the existing technique is not 100% efficient either.

Re: just put a motor on the elevator itself

[arth1]

Elevator brakes are one of the most elegant solutions known to man, and perhaps more crucial to the continued popularity of the cabled elevator. The brake is held open by spring tension generated by the interaction of the elevator and the cable. If the cable gets cut, the brake engages. That's it. Any other type of elevator would need a more complicated break system. Detection of fault conditions would be a separate action that triggers the brakes. That means delays, and the possibility of errors. It is practically impossible for a properly built cable elevator to plummet. You cannot say the same for any cableless concept design. One of the simplest ideas in legal liability is that if you opt to do something the more dangerous way, you're liable. You must have very good grounds to justify the risk.

You miss that in a pinion or cog driven elevator with the motors in the building, there is no need for emergency brakes - being stationary is the default state. Only if a motor moves the cart along will it actually move - up or down.
To me, that seems like far less risks than having a system where you need emergency brakes for safety, no matter how elegant.

And this system is in use in many assembly lines. The motors are stationary, and the carts won't move unless driven. And while most are horizontal systems, there are vertical ones too. Boxes with holes or pinions on the side are lifted or lowered by cogwheels, and there is no possibility of them falling. They can reach quite high speeds too, unlike the typical self-driven pinion-and-rack lifts that you see on boatyards and libraries.

Re: just put a motor on the elevator itself

[LynnwoodRooster]

You don't need sliding rails if you use magnetic coupling, like a maglev train...

Re: just put a motor on the elevator itself

[guruevi]

Huge capacitors for one. You can take most electric trains (with overhead electric wiring) off the power for quite some time. Arcing is not a huge problem, the problem is lifting the weight of the larger motors, capacitors thus requiring larger brakes and safety features etc. and not to talk about the noise thus requiring insulation.

Re:just put a motor on the elevator itself

[gzuckier]

Bussard ramjet engines.

Re:just put a motor on the elevator itself

[aurizon]

This will work, but will use more power because current elevators are counterweighted so power is used to raise the live load(cargo or passengers).
In effect a vertical cog railway. They could also make it move laterally, as the moving lights on Star Trek anticipated this idea.
A few companies are working on this old concept, which has not gained much traction due to the larger needed numbers of empty passages for cars to traverse. The nature of the idea allows multiple cars on the same track and the laterals would allow passing via temporary use as a car siding.
Taller structure are going to require longer shafts as well as sky lobbys, and stronger cable will mitigate this need in part - the number of people in taller structures will still require sky lobbys in most cases.
Regenerative descent and battery packs beside the rails are also worthwhile. Moving batteries up and down might be too costly in power? but regeneration will help in this

Re:just put a motor on the elevator itself

[Noah Haders]

regenerative descent is interesting. This way even though the elevator will still require big motors and may accelerate slower, the power required will be less.

the self propelled elevator starts to make sense at a certain elevator shaft height. eventually with really long shafts the weight of the cable dwarfs the weight of the passengers and becomes an off-balance load, requiring bigger motors to handle. Also see my comment below about the coolest idea ever for "spider" elevators that climb along the outside of the building.

Re:just put a motor on the elevator itself

[metaforest]

The current approach uses a counterweight that balances out the empty mass of the elevator cabin. This drastically reduces the load the motor must carry, and thus the size of the motor. If you want to put the prime mover on the cabin you are going to have to solve a lot of scaling problems that the current approach avoids.

Re:just put a motor on the elevator itself

[Noah Haders]

actually I disagree with you about scaling problems. The central issue in this discussion is that the counterweight system doesn't scale well because above a certain height the cables become too heavy. The self propelled system works at any height with no scaling issues.

Re: LOLOLOL

[ihtoit]

In tribute to the late, great Robin Williams:

Ask Dr. Ruth. No, not the short Jewish woman, the big black mama called Doctor ROOF!

"Ya can't make butter wid' a toothpick!"

What?/ Just 2 Km? That's it?!

[140Mandak262Jamuna]

So I guess the space elevator is not coming any time soon.

Re:What?/ Just 2 Km? That's it?!

[w_dragon]

2km for a building full of usable space like offices and hotels. A space elevator only requires a cable. That said, no, no space elevator any time soon.

Re:What?/ Just 2 Km? That's it?!

[Kevin Fishburne]

Instead of a two kilometer tall office building they should build a two kilometer tall railgun. Then design a super aerodynamic, heat-shielded carrier with a late-firing chemical rocket for satellites and spacecraft payloads that can be launched from the rail gun. If there were stability issues (could be tied down with cables, I suppose, like a radio tower) they could build half of it underground, though I don't know how much momentum they'd lose from having to travel the extra distance.

Re:What?/ Just 2 Km? That's it?!

[Anonymous Coward]

How about "never"? Does that work for you?

Re:What?/ Just 2 Km? That's it?!

[Anonymous Coward]

I don't think many people would fancy the idea of working inside a railgun, though.

Re:What?/ Just 2 Km? That's it?!

[Kevin Fishburne]

Eh, they could just have a red light that turns on when it's about to fire and some crap to sign when they hire you. And paperweights, of course.

Re:What?/ Just 2 Km? That's it?!

[Anonymous Coward]

No, it doesn't. I'm sick and tired of having to take the stairs.

Re:What?/ Just 2 Km? That's it?!

[jrumney]

2km? I'm pretty sure I heard somewhere about an ancient construction technique that can support structures up to 8,848 m.

Re:What?/ Just 2 Km? That's it?!

[Anonymous Coward]

Well, there were mines that are 8000 meters deep in eastern Canada and they had lifts - ditto for 3000 meter mines in South Africa. So this a typical bullshit story.

Re:What?/ Just 2 Km? That's it?!

[coofercat]

We'll have the space elevator, just as soon as we find someone who's a bit too rich with a dick that's a bit too small that wants to build a monument to themselves.

Re:What?/ Just 2 Km? That's it?!

[Bob the Super Hamste]

But that isn't vertical construction. Anyone can make a big pile of stuff and I am pretty sure my kids have made a bigger pile of their things.

Yes I get the reference, and yes I am sarcastic.

Re:What?/ Just 2 Km? That's it?!

[andydouble07]

This would only help with the first 10% of getting into orbit. The hard part is getting moving sideways so damn fast.

Re:What?/ Just 2 Km? That's it?!

[Kevin Fishburne]

Good point, although it would be useful for launching probes and such.

The rate at which oil prices are dropping ...

[140Mandak262Jamuna]

... we may have use the 2km long ultra strong ultra light cable to dredge the Saudi economy from the bottom of the Persian Gulf.

Re:The rate at which oil prices are dropping ...

[Anonymous Coward]

where you been? prices at the pump already going back up.

Re:The rate at which oil prices are dropping ...

[ihtoit]

alternatively we could just invent another pretext to invade Syria so we can grab up the land and finish the Qatar gas pipeline.Then oil can do what it wants and Russia can go fuck itself since Eastern Europe will then have another source of natural gas.

Colour me cynical.

Re:The rate at which oil prices are dropping ...

[Lunix Nutcase]

Sucks for you. Still going down every day where I live.

Re:The rate at which oil prices are dropping ...

[ShanghaiBill]

... we may have use the 2km long ultra strong ultra light cable to dredge the Saudi economy from the bottom of the Persian Gulf.

Nope. The Persian Gulf is very shallow, with an average depth of only 50 meters, and a deepest point of only 90 meters. Citation: Persian Gulf Geography

Re:The rate at which oil prices are dropping ...

[Fjandr]

Most of the Arab nations actually have massive diversified investment schemes that will allow them to continue being rich even without oil. Of course, it's easier for the smaller ones like Dubai and the UAE, but Saudi Arabia has been unhitching as many of their economy's horses from oil as they can for a long time.

Re:The rate at which oil prices are dropping ...

[RockDoctor]

Errr, you do realise that it's the Saudis who are primarily behind the current drop in oil prices?

trains don't need rope...

[Anonymous Coward]

trains don't need rope to pull them the full distance of the track. the elevator engineers just need to stop putting the electric motor on the building, and put it on hte elevator. simple.

Re:trains don't need rope...

[luvirini]

Trains also do not need to pull straight up.

The real reason for the cables is to allow counterweights to balance much of the load. Thus with counterweight you are lifting only the carried weight, without you are lifting also the elevator chassis and any engine and such, a much larger load.

Re:trains don't need rope...

[ihtoit]

that's the ticket - you want the car + load to be as light as possible. Basically all you want on the car is the anchor point for hte rope, some way to get power inside the car and power for the emergency system. That's enough weight, the big building that isn't going anywhere can take the several-hundred-pound motor and gearbox and keep it sequestered in the roof.

Elevator scheduling

[Anonymous Coward]

I can only see one purpose for ultratall elevators: skipping the intervening hundreds of floors.

Re:Elevator scheduling

[Half-pint HAL]

You have failed me for the last time, Admiral.[Chokes Admiral Ozzel using the force.] You are in control now, Admiral Obvious.

Worthless

[Sir_Substance]

We still won't see elevators 1km in hight, there's a queuing problem involved.

Basically, if you have 100 floors, and 8 elevators that service all 100, the chances that there will be one a) free to pick you up and b) close to the floor you are on are very low. Even with efficient lift allocation systems, you can end up waiting 15 minutes for a lift.

It is much faster to have 40 elevators, each servicing 20 floors, and change lifts every 20 floors. Yes, if you're going from floor 1 to floor 100, you have to make 4 changes. However, if you're going from floor 1 to floor 18, it'll be a fraction of the wait, and even if you *are* going to floor 100, it will still be much faster on average, even though you have to repeatedly change lifts.

Re:Worthless

[Baron_Yam]

With electric elevators riding vertical rails, you can do switching. Essentially, with three or four sets of rails (one up, one down, a couple for parking) you can put as many cars in the same set of shafts as you want - and even have a supply of extras waiting in a subbasement to be added when required.

Re:Worthless

[Anonymous Coward]

they solve this by having express elevators, that go from floor 1 to 90-100, etc.

Re:Worthless

[Anonymous Coward]

In theory yes.

In practice, it is far more difficult to have independently movable cars meet the same safety standards as cars that are fixed within a track. That's why there are so many vehicle accidents on the road compared to the number of escalator stairs running into each other.

Re:Worthless

[quenda]

Another way is to have long, fast express elevators stopping every 20 floors of the top half, and ground.

Re:Worthless

[Anonymous Coward]

If you created periodic bypass junctions you could even allow cars to pass each other and eliminate switching all together.

Re:Worthless

[TechyImmigrant]

Or build the building horizontally and put in moving walkways.

Just as much space, at a fraction of the cost and it doesn't have to exist to massage the ego of an oil rich prince who murders atheists for fun.

Re:Worthless

[Anonymous Coward]

I hate escalator stair pileups...they are such a pain to clean up and fix. It forces all floor travel to manual stairs of elevators and really backs up traffic flow for hours.

Re:Worthless

[ShanghaiBill]

If you use cables, you are limited to one elevator per shaft. But if you eliminate the cables, and put motors on the cars, then you can have many elevators per shaft. You can even move the elevators between shafts, going up in one shaft, and coming down in another, in a loop. One pair of shafts could run an express loop, that stops only on floor 1, 20, 40, 60, etc. Another pair of shafts could run a slower loop that stops on every floor.

Re:Worthless

[Anonymous Coward]

You are assuming that there is no need for an elevator for executives/kings who skip floors and are not subject to queuing with the proletarians.

Re:Worthless

[Anonymous Coward]

This solution has loads of problems, but yes, these exist. At least on paper. I haven't heard of anyone actually buying the solution yet. If you want to order one contact ThyssenKrupp.

Re:Worthless

[Anonymous Coward]

I like your thinking.

We've been doing it wrong all this time.
Wasting time and energy building upwards when we could easily be building flat buildings and have escalators everywhere.

Re:Worthless

[Anonymous Coward]

We still won't see elevators 1km in hight, there's a queuing problem involved.

Basically, if you have 100 floors, and 8 elevators that service all 100, the chances that there will be one a) free to pick you up and b) close to the floor you are on are very low. Even with efficient lift allocation systems, you can end up waiting 15 minutes for a lift.

It is much faster to have 40 elevators, each servicing 20 floors, and change lifts every 20 floors. Yes, if you're going from floor 1 to floor 100, you have to make 4 changes. However, if you're going from floor 1 to floor 18, it'll be a fraction of the wait, and even if you *are* going to floor 100, it will still be much faster on average, even though you have to repeatedly change lifts.

The solution to this is to have different elevators with different service lengths. So you have an "express" elevator that does the full height, but only services every tenth floor alongside the short-range elevators that service all floors within their range.

People who need to go up a large number of floors will use the express elevator to get to the nearest tenth floor to their destination, and then switch to the short-range elevator for the last few floors (or they might even use the stairs at that point if they feel like it). So even those going a long distance will only need to change once.

In addition, the floors serviced by the express elevator will also be the floors most likely to be a final destination -- eg the restaurant floor or the viewing gallery -- so that as many people as possible can get to their destination without having to change at all, even in a very very tall building.

Re:Worthless

[IamTheRealMike]

Indeed. I once read that the limiting factor on how high we can build skyscrapers is not structural engineering but the explosion in space occupied by elevator shafts as you try and go higher and higher whilst preserving reasonable wait times.

Re:Worthless

[PrimaryConsult]

The skylobby design works well enough - to get from the ground to any floor requires a maximum of one transfer, and elevator shafts can be stacked. The (original) NYC WTC towers for example had an elevator pattern which was:
Express elevators to floor 44.
Express elevators to floor 76.
Shuttle express elevator between 44 and 76 that didn't go to the ground level.
Local elevator banks served groups of 7-8 floors and would only take people to the nearest skylobby (or the ground for the lower third of the building).
Tourist / freight elevators which could stop at 2, 44, 76, and 107 (possibly also 106, I forgot).

The only drawback of this design was, if you wanted to go from, say, floor 77 to floor 73, you would have to take 3 elevators (with transfers on 76 and 44). But the overwhelming number of elevator trips in any building involve the ground floor anyway, so this isn't really a big deal.

Re:Worthless

[Half-pint HAL]

In addition, the floors serviced by the express elevator will also be the floors most likely to be a final destination -- eg the restaurant floor or the viewing gallery

...or in the case of a building over the height of 1.6 km, the "Mile High Club".

Re:Worthless

[Anonymous Coward]

Or build the building horizontally . . .

They did. The problem is that the building was just so fucking wide.

Re:Worthless

[Baron_Yam]

The reason for vehicle accidents on the road would be human operators, not the ability to switch lanes.

Why use a cable?

[fuzzyfuzzyfungus]

Does anyone know why they wouldn't sidestep the infeasibility of particularly long cable runs by having the elevator climb the walls of the shaft directly, rather than being raised and lowered on a cable? I imagine that a cable and counterweight arrangement is more energy efficient for shorter runs; but if that isn't an option wouldn't a cog railway style mechanism, with 'track' on one or more walls of the elevator shaft, result in a system where the weight that has to be moved doesn't change at all with the height of the building? There would be some additional weight per unit height from the track structure; but that would be static and connected to the building's frame rather than being forced to support its own weight.

Too energy intensive? Wears too quickly? Safety breaks infeasible leading to risk of sickening plummet to doom?

Re:Why use a cable?

[Baron_Yam]

It's mostly the counterweight issue, which you can resolve by using electric motors in the cars and large battery banks.

Draw power on the way up, generate power on the way down. There are losses, of course, but it's doable and not terribly inefficient.

The regulations for battery maintenance make it prohibitively expensive. I think there's only one or two such installations in existence.

Re:Why use a cable?

[Anonymous Coward]

http://spectrum.ieee.org/tech-talk/transportation/mass-transit/maglev-elevators-will-take-you-up-down-and-sideways-by-2016

Re:Why use a cable?

[ArsonSmith]

that was my first thought as well, until someone pointed out that it's not the cable to the motor that's the problem it's the up and over then attached to the counter balance that is the problem.

Re:Why use a cable?

[turbidostato]

"It's mostly the counterweight issue, which you can resolve by using electric motors in the cars and large battery banks."

Cuonterweight is there to avoid the need of hugh power-hungry engines, since they only need to lift the load. Take out the counterweight and you will need to lift the whole load requiring a much bigger engine. Put the engine on the car and then you'll need an even biigger engine (much bigger) to lift its own weight too.

Re:Why use a cable?

[quenda]

Such lifts certainly exist, and are used on construction and industrial sites.
I expect noise, speed, power use and maintenance cost might be areas where cable wins out.

http://www.gedausa.com/rack-an...

Re:Why use a cable?

[ihtoit]

car weight. Bear in mind you're lifting a deadweight vertically potentially through several hundred feet. That is a LOT of gravity well to overcome. The lighter your car, the better. If your combined car+rope is lighter than car+cable+attached motor for the same shaft, it makes sense to go with the cable and offload the motor to the building that isn't moving.

Re:Why use a cable?

[aaarrrgggh]

Agree, but a hybrid approach is likely the most efficient. Get 50% of the power/braking from the rope and 50% from a cab-mounted motor. Batteries aren't needed; just regenerate into the rails.

The other interesting challenge is water. Every 200m you need a pressure break because the welds in the pipe reach pressure limits. An extremely tall building needs to deal with these issues cost effectively, and efficiently-- think water treatment every 40 stories to recover grey water, treat potable water, recover condensate, etc.

Hell, from an IT perspective you reach the limits of multimode fiber risers pretty quickly.

Re:Why use a cable?

[bluegutang]

Cog railways are way too slow...

Re:Why use a cable?

[Anonymous Coward]

"more energy efficient for shorter runs". We're talking about elevators, you know, those things that stop every 3 vertical meters.

Re:Why use a cable?

[Anonymous Coward]

That's one of the limits to building a bigger and bigger skyscrapers is that at some point the first floor would be nothing but utilities for the floors above it. And the second floor wouldn't have any usable space, anyway... So it't more like when does adding an extra floor start to take away more space then it adds to building's floors below it.

Re:Why use a cable?

[prisoner-of-enigma]

Hell, from an IT perspective you reach the limits of multimode fiber risers pretty quickly.

That's why God invented single mode fiber.

Re:Why use a cable?

[stephenpeters]

I think one of the reasons is that it is possible for fire fighters to manually move the winding drum in the event of a power failure to move the lift car to the nearest floor. Without a drum and cable any rescue attempt during a power loss would require lifting equipment and would involve climbing into the lift shaft to reach the car with all the related falling from height issues.

Re:Why use a cable?

[Half-pint HAL]

Hell, from an IT perspective you reach the limits of multimode fiber risers pretty quickly.

Yeah, but the lag on the satellite broadband suddenly drops away...

Actually, if you're building a tower that high anyway, you'd be just as well using it as a pseudo-satellite broadband provider -- the horizon is over 100 km away when you're a kilometre up. You can serve wireless internet to a small country from up there....

Re:Why use a cable?

[Half-pint HAL]

"more energy efficient for shorter runs". We're talking about elevators, you know, those things that stop every 3 vertical meters.

No we're not. We're talking long-distance elevators. Or do you think someone will ever get to the top floor of a 1km high building if the car stops at every floor. Every time you're almost there, you'll have to stop for a pee break then wait for the car to come back.

Various skyscrapers have extremely high capacity lifts -- the Petronas Towers have double-decker lifts with a capacity of 52 passengers.

Re:Why use a cable?

[aaarrrgggh]

You can make a group of 10-15 40,000 square foot floor plates operate with a substantial amount of recirculated utilities-- bring up just natural gas and you have a source of electricity, heat, and water; just send down black water or even sludge from sewage. It starts to get cost effective today at about 1MM square feet, but when you factor in the cost of risers and pumping it might start to scale down. The linear motor elevator concept, with multiple independent cabs in directional hoistways (up/down) reduces that impact, and currently ultra tall buildings do not plan on evacuating everyone to the ground via stairs, so that isn't an impediment.

Structurally, much over 800 floors would be quite difficult as the concrete to support the gravity load of the building would start to take up half the floor area at the base, but stepped buildings can assist with that-- 10x floor area at base might give you a reasonable useable area. Wind or seismic loads would need to be dealt with by active systems... Not sure how well that would go over though.

Re:Why use a cable?

[Baron_Yam]

Yes, but we have big elevator cars because of the 'one car per shaft' limit. Remove that limit and you can have smaller cars, and smaller weights.

And whatever weight you add (drawing more power to go up) results in generating more power on the way down.

You use batteries and capacitors (or even just other elevators descending at the same time as another is ascending) as your 'counterweight'.

Re:Why use a cable?

[turbidostato]

"You use batteries and capacitors (or even just other elevators descending at the same time as another is ascending) as your 'counterweight'."

For that to work you need to link them... with a cable. So back to square one.

Maglev elevators

[Anonymous Coward]

Maglev elevators are coming and they can go sideways also, but apparently they aren't ready yet for some reason.
http://spectrum.ieee.org/tech-talk/transportation/mass-transit/maglev-elevators-will-take-you-up-down-and-sideways-by-2016

I'm remded of the Tower of Babel

[Anonymous Coward]

On the other hand, if it was a cube, a kilometer on a side, it would make Niven and Pournelle happy.

Re:I'm remded of the Tower of Babel

[Anonymous Coward]

As long as you swore an oath of fealty.

LSM

[jklovanc]

Linear Synchronous Motor Elevators Become a Reality

Re:LSM

[Anonymous Coward]

Well this is the best thing I've seen! Why haven't these been pushed out into the commercial area? And why is your post stuck down here and not at the very top?

Re:LSM

[Anonymous Coward]

Permanent magnets and copper are expensive. Most people would rather pay the higher total cost of ownership to defer the initial capital expense of burning through the world's limited supply of rare earth metals on people movers because "stairs are hard". It's economics meets engineering. Physics is about what is possible, engineering is about how to get there, and business economics is about allocating the limited resources available to the most promising efficiency improvements made possible by better engineering.

Any engineering which can't justify itself as a business investment probably isn't worth doing. To claim otherwise is adorable, but ignores the opportunity costs in the zero sum game. Every long term ROI engineering project which gets subsidized by the government comes at the expense of inflation eating the profit margins of other ventures which ROI fast enough to exist without government subsidy.

I say this as an engineer who has seen millions of tax dollars thrown at feel good pipe dreams that aren't economically competitive without government assistance for good reason. The purity of the argument becomes corrupted by the realities of anti-competitive practices in the global marketplace like the "dumping" that Saudi Arabia is doing right now to kill off petroleum startups.

Suggested response: increase market volumes so that these schemes can be busted the same way as the Hunt Brothers and the Swiss Franc.

Re:LSM

[Warbothong]

Well this is the best thing I've seen! Why haven't these been pushed out into the commercial area?

For the same reason that maglev trains and HyperLoop-style vacuum tubes aren't ubiquitous: sending a dumb carriage along a smart track is far more expensive than sending a smart carriage along a dumb track, since there's much more track than there is carriage.

Narrowboats used to be the best way of moving materials around in-land, but "laying the track" (digging the canals, building the locks, etc.) took a lot of work.

Dumb boats were overshadowed by smarter locomotives: more difficult and expensive to build, but ran on much cheaper tracks.

Locomotives were overshadowed by smarter automobiles: more difficult to invent and require a smarter fuel network, but in some cases don't need *any* track laying.

The same argument applies to lifts: it's much cheaper to have a smart motor at the top and/or a smart carriage, with 660m of dumb shaft and cable, than having 660m of smart shaft.

Re:LSM

[jklovanc]

On a one for one basis I can see your point. The calculations get different when you can replace banks of elevators with a couple of shafts. It also reduce the floors pace on each floor taken up by shafts. A LSM elevator can cost many times the cost of a rope elevator but still come out less expensive in the long run. Then there is the issue of vary tall building that even the new rope can not handle. Neither of us have the numbers so we have no idea where the break even point is.

World's highest dick-waving contest

[localroger]

Highest skyscraper is a hell of an expensive way to show your ability to get an erection. How much of the Burj Dubai is even occupied? Or for that matter even the *cough* whatever they're calling it now in NYC which gets a third of its patriotic 1776 feet from a totally nonfuctional dick-waving spire.

Re:World's highest dick-waving contest

[Anonymous Coward]

Consider this: the people who complain the loudest about dick waving contests have the smallest dicks...

Re:World's highest dick-waving contest

[Anonymous Coward]

How much of the Burj Dubai is even occupied?

Dude, Dubai is so primitive that the Burj Dubai (and many other big towers) isn't even connected to the sewer system:

http://inhabitat.com/the-incre...
http://gizmodo.com/5857475/wit...

Re:World's highest dick-waving contest

[Anonymous Coward]

Well that's the solution then. Burn the poop to generate power for the elevators.

Re:World's highest dick-waving contest

[LongearedBat]

I went to the top of Burj Dubai* in May last year, and I couldn't see anything that made it look useful for anything other than a tourist platform. If such buildings eventually bring in more tourist dollars than they cost to build, then I suppose they serve their purpose.

* Does that mean that I mounted Dubai's... oh, let's not go there.

Re:World's highest dick-waving contest

[Anonymous Coward]

The name of the building is Burj Khalifa.

Re:World's highest dick-waving contest

[coofercat]

It's okay, I'm sure tourists from all over the world will literally flock to Jeddah to have a look at the world from that high up. Oh wait... it's Saudi which doesn't do tourist visas... maybe not then.

Nice technology, wrong description

[Anonymous Coward]

Strength limit of the cable is not the reason for elevator lobbies on tall buildings. The elevator lobbies are there because it would take an unreasonable number of elevators to provide acceptable latency if every trip could require traversing 300 floors with an arbitrary number of stops. [Edit: I got "herrings" for a captcha on the first try. There must be a parrot in here somewhere.]

Electrically-coupled counterweight

[Aardpig]

Many posts suggest doing away with the cable by putting the motor on the elevator car; but this overlooks the fact that the elevator needs to be connected to a counterweight for efficiency reasons.

However, here's a thought: you put motors on the elevator *and* the counterweight. As the elevator goes up, the counterweight goes down and uses its motors as generators to partly power the elevator's motors. And vice versa.

Sure, you're not going to break even due to electrical losses; but it'll be a damn sight better than no counterweight.

Re:Electrically-coupled counterweight

[Anonymous Coward]

That's not really a counter weight, since you wouldn't mechanically link them via a cable and pulley. The weight or opposing car would be a battery. You might be able to use other energy recover systems like fly wheels or pressurized fluids too. Compared to hybrid cars, the elevator has a much more restrictive operating regime and the power budget can be carefully considered...

Re:Electrically-coupled counterweight

[Dereck1701]

While such an elevator system would use more power one of the inherent abilities of any electric motor system is the ability to use regenerative braking. You'd probably have a bank of super-capacitors in a utility room, when the elevator was going up it would use the capacitor bank and some power from the mains, when it was going down it would refill the capacitors. Even if you had to put the motors on the elevator car itself this shouldn't be an issue as we have centuries of technology (subways, trains, trolly cars, bumper cars, etc) proving that you can provide power to a moving transportation system and electric motors are quite small (the ones powering electric cars are about the size of a watermelon).

Friction proof?

[Anonymous Coward]

TFA says "high friction".... Geez, guys...

Re:Friction proof?

[Le Marteau]

TFA article says nothing of the sort, actually. It's TF submitter. Slashdot, of course, simply copy-pastes anything Hugh says.

Armchair engineering at its finest

[mcrbids]

I'm probably going to lose some karma for this...

I, too, could come with a half-dozen answers that would be "far superior" to what 100+ years of the finest minds in the industry could come up with. But in reality, I really, seriously doubt that my designs would hold up because there's a *reason* that things are done the way they are.

Mechanical engineering is a *very old* industry, and any radical, new design would have significant hurdles to pass before it could be accepted and used in a real scenario. The cost of failure is very high and there are real lives on the line.

My first thought was to use something like a caterpillar drive along the sides of the shaft, each of which would operate like a mini elevator for perhaps 10 floors. But, very quickly, I can see that this type of system would have many, many more moving parts and consequently many more points of failure.

So, I think it *might* be best to trust that 100+ years of experience are, in fact, at work, and that we should first understand that there is *real knowledge* at work before assuming that our half-baked and thoroughly unproven ideas hold any merit in reality.... ?

Re:Armchair engineering at its finest

[NoNonAlphaCharsHere]

That has GOT to be the most trollish post I've ever ever ever read here. You have NO IDEA how Slashdot works, do you?

Re:Armchair engineering at its finest

[Anonymous Coward]

I'm not a mechanical engineer but I did stay at a holiday inn express last night...

I'm assuming the goal here is to build a space elevator cause it's the only reason anyone cares about these super exotic high tensile strength/weight ratio ropes. When you're interested in fibers for composites: it's not about the rope/cable but about the individual fibers.

If you have 2x ropes/cables to flow electricity you will have to deal with tangling on some sort of trapeze basis. Since we're already dealing with unobtanium materials: doubling the price for unknown reasons is asinine.

Ok: so fuck confounding variables like confusing tensile strength with conductivity in some sort of dual purpose two birds with one stone safety disaster... What then?

That leaves a "pulley" type arrangement which uses the same amount of material as the trapeze, or a single strand of cable/rope which necessitates the "car" can absorb ground transmitted energy or self propel itself up the rope. Called "jugging" by climbers IIRC.

Ground transmitted energy using tuned antennas and the cable itself as an inductively coupled antenna seems like the easy answer to me, but supposing we're only concerned with the conservation of energy here: you can do the math and find the derivative of weight to geosynchronous orbit(payload fraction) with respect to weight of stored energy(assuming diesel/methane as the energy storage vehicle). Assume electric motor efficiency of 99% you can get a pretty good idea of how that solution scales compared to rockets and see if it requires a nuclear reactor to make hay.

So if this space elevator has a 98% efficiency: what is the potential energy of a 1kg brick in geosynchronous orbit and how many of kg worth of gasoline is required to put it there? Divide by .98 and you have your "cable car" dead weight fuel tax per kg(ignoring the weight of the engine which is negligible compared to the fuel expense when scaled up).

Self propelled is the "rocket problem" and is best avoided by putting your energy source on the ground and transmitting the energy through some other means, even if that "means" is a solar powered fishing reel in space which reels in Droopy Dog every time it's time for "elevator up".

Re:Armchair engineering at its finest

[Anonymous Coward]

Coran is around 1400 years of experience and new testament 2000 years... Still they are full of bullshit.

Re:Armchair engineering at its finest

[serviscope_minor]

Indeed, and I think it's reasonable to call out the posters who say "oh they're idiots, why don't they just..." and so on and so forth.

However, it IS fun to speculate with a bunch of reasonably knowledgable people on mechanisms for going beyond what is currently technically feasible.

The powered lift with a rack and pinion is an interesting idea. I'm struggling to work out how much additional power it would take. With a short lift, you can discount the weight of the cable, and so you can have the lift counterbalanced easily and the motor must lift the ddifference between the two sides plus the friction.

With a long cable, the weight to be lifted changes with height: the further down the lift goes, the higher the weight. If you counterbalance with the same mechanism, then the balance will only be equal in the middle. At the bottom, you need to lift the entire weight of the cable, which in a high lift can be more than the lift.

At that point, having a motor which can lift the entire lift minus the cable isn't infeasible. Of course, you have to lift the motor too. And then there's the problem of power delivery. Maybe something like a train pickup could be adapted to work.

The power will be enormous, but one could offset it at a building scale using energy recovery, either have lifts run in oppsition where the descending one powers the rising one, or have the lifts all connected into a busbar which has some large piece of rotating flywheel storage to absorb or emit energy as required.

Apparently there are a few companies working on cableless elevators for exactly these reasons. Some have linear motors instead of a rack and pinion.

Re:Armchair engineering at its finest

[megahurts.gr]

dude, your signature is one of the best quotes I have ever seen.

Re:Armchair engineering at its finest

[Stuarticus]

You're on the wrong site, everyone on here knows better than everyone else who ever lived. I wonder if these "professional" mechanical engineers have considered using teams of highly trained monkeys, probably not because of all their book learning preconceptions.

Re:Armchair engineering at its finest

[megahurts.gr]

I can tell by the way you write that you are drunk. You should seek help.

Re:Armchair engineering at its finest

[Anonymous Coward]

The koran wasn't compiled over 1400 years.
Nor was the new testament written and compiled over 2000 years.
More like 40 years max for both.

Re:Armchair engineering at its finest

[CarbonShell]

Very true, but we also know companies and how they 'think'. Anything new would have to be proven by someone else because no one will take the risk.
And when we run out of options do do things, well then we have to think outside the box.

Though this is slashdot, so let's get creative. ;)

I also instantly thought about how roller-coaster cars are pushed up the rails. Also like how scaffolding is assembled and you have guys vertically in a row, passing on the pieces to the next guy above. Same could be done with the cabin. Kinda like how a mag-train is moved along the line, but with sprocket-flywheel kind of things. It would naturally mean more hardware employed, but unless all the sprocket-flywheels fail, it could be safer.
You could also theoretically employ more cabins in the same shaft.

Re:Armchair engineering at its finest

[Anonymous Coward]

> I, too, could come with a half-dozen answers that would be "far superior" to what 100+ years of the finest minds in the industry
> could come up with. But in reality, I really, seriously doubt that my designs would hold up because there's a *reason* that things are done the way they are.

Uh, no. Not always.

Too many times things stay the way they are because they are 'good enough' and not worthwhile to change. Then tech comes along, and it becomes worthwhile.

Consider the 'elevator close' button for instance , and how people always end up jabbing the wrong button. There was an HCI book that gave this topic very good treatment (book 'HCI Remixed', chapter "1+1=3. The impact of Edward Tufte on Interaction Design")

Re:Armchair engineering at its finest

[Anonymous Coward]

You just had to confirm the stereotype, didn't you?

Some days, when I am feeling particularly naive, I like to think that today might possibly be the day when people begin moving towards not being complete pricks when online.

Thanks for putting me straight.

Re:Armchair engineering at its finest

[Anonymous Coward]

No, brain tumor but thanks...

Re:Armchair engineering at its finest

[Hodr]

I wouldn't presume to know more than a mechanical engineer at an elevator company. But I might still be able to figure out why someone who has spent their entire career building one style of system, with the only variance being the size of the motor and the length of the cable, with investments into the supply chain for those specific components and technicians familiar with working and installing those components, might tell you that the old way is the best way without seriously considering an alternative.

Hey, I mean If I was staring at the choice of selling 10 of my most expensive systems to a client, or telling him to hire an engineering firm and materials scientist to reinvent the wheel (or elevator), I know which one is better for my bottom line.

Re:Armchair engineering at its finest

[Half-pint HAL]

Ah, rampant speculation -- I'm game. I'm wondering about the possibility of a three part lift -- a car with two independent cradles. The first cradle is cabled for a third of the height of the building, and is left behind when the lift goes above that point. The second cradle is cabled for two-thirds of the building, and disengages once the car ascends above two-thirds of the building. On descent, the car reaches the cradles again and continues down. Each of the cradles is counterweighted to provide a displacement load for the shifting weight of the cable. Each cradle would have its own independent brake (as would the car), which would add extra safety mechanisms to the lift

Now I'm also wondering if there's some way of using waste water from the upper floors as additional ballast, carried partway down the building alongside the counterweights before being released into the sewage system on a lower floor. Or maybe a partially-passive aircon using a liquid medium that is cooled by high-altitude winds before being shuttled to the centre of the building for circulation.

Re:Armchair engineering at its finest

[sumdumass]

Well, not only is it entrenched in that way, there are a lot of laws and regulations that detail the mechanics of an elevator. This is even before liability issues and indurance consideration even come into play. So it isn't that just anything else could be used either. Of course there is no telling how much of those regulations are because of what you mentioned and what is pure safety.

Re:Armchair engineering at its finest

[bluefoxlucid]

Often, the reason something's been done the same way for 100+ years is because we know it works, and experimentation is dangerous. Sometimes, it doesn't even really work.

Re:Armchair engineering at its finest

[cellocgw]

Yeah, I have to agree (sadly) with that conclusion. I wanted to come up with a semi-magical coupling system that would "hand off" one counterweight&pulley system to another every 100 floors or so, and do so without requiring the car itself to stop, but I rather suspect the cost and safety requirements would make this well-nigh impossible.

Heck, we might just as well go for a vertical version of the Hyperloop .

Re:Armchair engineering at its finest

[Noah Haders]

haven't scientists shown that when you shine a laser at something it imparts a bit of momentum to the object? maybe the elevator has a big shield on the bottom and there's a big laser at the bottom of the shaft? that seems like a pretty good way to do it...

Re:Armchair engineering at its finest

[Noah Haders]

that's actually a cool idea. I would call it the "Russian nesting doll elevator". but wouldn't this require that the inner cradle have a cable for the full length of the building?

Re:Armchair engineering at its finest

[cyberchondriac]

Such humble acumen shall not be tolerated here; This is SLASHDOT!! **kicks you down an elevator shaft

Re:Armchair engineering at its finest

[Trailer Trash]

I'm probably going to lose some karma for this...

I, too, could come with a half-dozen answers that would be "far superior" to what 100+ years of the finest minds in the industry could come up with. But in reality, I really, seriously doubt that my designs would hold up because there's a *reason* that things are done the way they are.

And, yet, some guy named Elon Musk - who never worked at Ford, GM, Honda, the guy's a nobody - is the one who's making all the money in electric cars right now. Why?

Now and then industries that have been around for 100 years get so stuck in doing things the same way and simply scaling it can't get over the hump where you have to say "we can't scale this way of doing it, we have to start from scratch". They also have a huge patent catalog related to their current way of doing things, a huge number of engineers who know this method inside out, etc. There's considerable inertia to overcome, and few companies overcome it.

That's why when things change it's often the newcomers who do it.

Here's another one - Vizio. Ever heard of them 15 years ago? They never made a CRT-based television. The founders came from a monitor manufacturer and decided to start making TVs based on LCD technology. They went straight to Sam's and Costco to sell them. They pretty much own that market now.

Meanwhile, where's Westinghouse? Or RCA? They turned out a ton of tubes back in the day, but they're gone. Nobody wants a freaking X-ray generator in their house now.

Honestly, I think a shakeup like this is long overdue in the elevator business. You say there are so many moving parts to your caterpillar drive - do you have any idea of how many moving parts are in a standard elevator. Your idea cuts the moving parts down to perhaps 1/10th of what there is now. Getting rid of counterweights is a huge deal. You can even keep the counterweight and change the traction to your idea and there are still far fewer moving parts.

Elevators were first made when a tall building was 10 stories. The idea that a radical overhaul in design isn't needed for buildings that are 20 times that tall is laughable.

So, yes, I think you're absolutely wrong. An outsider is almost certainly what is needed to scale elevators up like this.

Re:Armchair engineering at its finest

[Anonymous Coward]

Well, the AC was talking about Coran, not Koran.. :)

Re:Armchair engineering at its finest

[Lab Rat Jason]

there are real lives on the line

<slow clap>I see what you did there... </slow clap>

Re:Armchair engineering at its finest

[Lab Rat Jason]

Here's an idea: You can cut your cable requirements in half by lifting twice the weight, using a bogy:

So you have a cable fixed at the midpoint of the building. It rises up to a pulley on a bogy, then descends to the car at ground level. When the bogey is located at the middle of the building, the length of the cable need only reach to the floor. The bogy has a cable anchored to it that travels to the top of the building, connected to the motor, and of course another cable that passes over a pulley and then is attached to a counter weight, that is double the weight of the cab assembly.

As the motor draws the bogey up, the counterweight assists with the pull. The distance from the bogey to the centerpoint increases, which draws the cab upwards at twice the speed of the bogey, and when the bogey reaches the top, the cab has reached the top. It's technically more cable, but shorter lengths each, which solves the weight/strength problem.

Re:Armchair engineering at its finest

[Lab Rat Jason]

Last time I checked, Elon Musk wasn't pitching his ideas in Slashdot comments sections... a critical difference it would seem.

Re:Armchair engineering at its finest

[Half-pint HAL]

The main car would need a cable for the full length of the building. The problem with cables (if I understand the article correctly) is not the infeasibility of the length, it's the weight that comes with it. The point of counterweights is to have roughly similar weights either side of the fulcrum (ie the winch), but when there's a lot of cable, the long end is going to be heavier than the short end. My point isn't to reduce the cable length of the main car, but just to compensate for the change of weight as the cable moves from one side of the winch to the other.

Re:Armchair engineering at its finest

[LordWabbit2]

So what you are saying is that we should all STFU and not speculate and toss ideas around about a better mouse trap because we already have a working mouse trap. I have another idea, you STFU and we will toss ideas around about a better mouse trap. You do realise this is /. and there are actually mechanical engineers taking part in the discussion, sure most of the commenters are armchair engineers, but sometimes a bit of "outside of the box" thinking can open new avenues of thought. Either that or make a lot of mechanical engineers shake their heads and grimace.

Or shorter buildings

[Anonymous Coward]

Or, you know, we could stop creating buildings that tall like it's an architectural dick size contest.

Worlds Highest Rope...

[DrunkenTerror]

Made of Hemp

Re:Worlds Highest Rope...

[Anonymous Coward]

Wow dude. My hands look weeiiirddd.

"friction-proof" != "high-friction"

[l2718]

A frictionless cable (as described by the summary) would be practically useless. TFA says the cable has high-friction coating, which makes a lot more sense.

Elevators are no fun

[Anonymous Coward]

Just have Godzilla or King Kong pick you up and put you on the roof.

World's highest dick-waving contest

[Anonymous Coward]

Living in Saudi Arabia at the moment I can state the following:

1) Highly unlikely this thing is actually finished.
2) If it is finished, no way in hell I would ever visit, nevermind actually work/live there.

Better Way

[JimSadler]

The RCA building in NYC uses compressed air and the elevator is effectively a dart flying up the shaft. With an accelerometer installed to trip the brake if too rapid a descent occurs there is no need at all for cables.

Dyneema

[CBravo]

There are examples of cable that are strong enough in long stretches (2.5km), light (~10kg) and have a high break strength. Such as used in a glider winch. I guess there are extra demands to an elevator.

Re:Dyneema

[Anonymous Coward]

There are examples of cable that are strong enough in long stretches (2.5km), light (~10kg) and have a high break strength. Such as used in a glider winch. I guess there are extra demands to an elevator.

high breaking strength is relative, that cable would not be strong enough for even the smallest elevators. you need a strength an order of magnitude greater than that cable.

Re:Dyneema

[Snuggles]

The elevator rope has to be flexed around the top wheel quite a few times during its lifetime. Dyneema can't take that much repeated bending.

hello turbolift? Re:LSM

[Fubari]

That was a cool article, thanks for the link, this part made me think StarTrek style turbolift:
from the linked article (emphasis added):

Flexible configuration: LSM elevators can propel a vehicle in any direction, and cabs can be switched from hoistway to hoistway, enabling the creation of “one-way” hoistways with multiple cabs in each. Modular stators allow the height of the elevator to be customized at installation and extended in the future with minimal disruption. LSM elevators can also accommodate inclined layouts, providing an alternative to stairways or escalators.

Linear Synchronous Motor Elevators Become a Reality

Re:hello turbolift? Re:LSM

[painandgreed]

Flexible configuration: LSM elevators can propel a vehicle in any direction, and cabs can be switched from hoistway to hoistway, enabling the creation of “one-way” hoistways with multiple cabs in each. Modular stators allow the height of the elevator to be customized at installation and extended in the future with minimal disruption. LSM elevators can also accommodate inclined layouts, providing an alternative to stairways or escalators.

Sounds like a Wonkavator.

Forget elevators!

[Anonymous Coward]

Use a ring platform.

https://www.youtube.com/watch?v=ay7FwOKNp6M

Re:"friction-proof" != "high-friction"

[Anonymous Coward]

I disagree. A frictionless cable would be unimaginably useful, just not for this application.
But yeah, surprise, the TFS got it wrong again.

"friction-proof" != "frictionless"

[Anonymous Coward]

Friction-proof means it can withstand high friction. Of course it has to also be grippy, i.e. have a high friction coefficient.

just put a motor on the elevator itself

[Anonymous Coward]

There are this kind of solutions, they are not really useable for other reasons. Maintence for one, safety for another, lack of counterweight, big noise. After you engineer around all of those the end result is more expensive than the version with motors on top.

Some elevator maker just published a solution where the elevator cabins can even move sideways. Maybe it's financially feasible, maybe not, remains to be seen. Kone has done research into that direction also, but so far the old style of doing this has proven itself better.

One lift per lift well is not efficient either

[aberglas]

A big building will have a lot of people and require a lot of lifts. If there is only one lift per well then there will need to be a lot of wells. Most of the building, in fact, would end up as lift well.

The solution is "simple". Allow multiple lifts per well, and allow the lifts to overtake each other. All while dangling on this new tech rope. Hmm.

Re:One lift per lift well is not efficient either

[aberglas]

Or, just have stops along the way.

There only needs to be one lift that goes all the way to the top, and that is only for the King.

Another issue is that it takes more time for even a fast lift to get all the way to the top of a large building. So the number of transactions per hour goes way down.

Re:One lift per lift well is not efficient either

[Anonymous Coward]

Since transfers between elevators are probably essential (regardless of cable design/strength) there are some interesting ways to improve the transfer process:

1) Open doors directly between two shafts so that the occupants simply step over to the next elevator.

2) Install a transferable "box" inside the elevator that can be linearly shunted over to another shaft without the occupants noticing. Slight delay, but easy to use.

3) Or, do what they do now and have transfer lobbies.

Seriously, I can see why (3) is the way it's done now. Nice and cheap.

Vertical Maglev feasible?

[Qbertino]

Would a vertical maglev be feasible? ... It would be worth a try. ... However, I guess a handful of buildings becoming to high for our current tried and trusted elevator technology is a luxury problem.

Have you noticed that all of these tall buildings

[Chrisq]

Have you noticed that most of these tall buildings are in Muslim countries *? You know the reason? Its because contrary to the popular press it really isn't an equal chance that the next 9/11 will be committed by Christians, Buddhists or Atheists. Build something taller than the Muzzies and you would be inviting them to destroy it.

* China is a bit of an exception as it is much better at handling the Muzzie threat

Rope?

[Dereck1701]

Rope and cable for elevators is a century old technology, I'm surprised they aren't using linear motors, standard electric motors or something else for record breaking skyscrapers. I can understand continuing to use cable for normal skyscrapers as it is a tested, widely available and is cheaper due to current production. But when dealing with such immense heights (1km) you would think someone would have the sense to develop something better suited rather then putting a small metal box on the end of a giant spool of rope/cable.

Re:Rope?

[Anonymous Coward]

Can you imagine having such powerful magnets a few feet from thousands of office spaces? Pacemakers, ear implants, credit cards, maybe CRTs, etc... might all react badly to the fields. Factor in the hundreds, if not thousands of uses per day, and you've got lawsuits and dead people on your hands.

Anyways, it would cost a fortune to put in so many magnets and that much copper wire and that many Mumetal magnetic shields...

Why have top to bottom elevators?

[Anonymous Coward]

Each shaft then only serves a one of ~285 floors at any given time. How much floor space are you willing to give over to elevator shafts (non-revenue space) in order to keep the wait time down to something reasonable. At 4m/s (allowing for human comfort) an express to the top would return to the ground floor every 8 minutes. Add stops and it gets longer. Factor in the potential population of the building and load limits on the cars and you'll need an enormous bank of shafts to keep the tenants (revenue) happy. One solution: devise an enormously complex system to allow multiple cars in a single shaft. Or add sky lobbies and change elevators allowing 2 or 3 cars per shaft and eliminating the need for exotic cables.

Tallest building for now.

[Anonymous Coward]

But will it be resistant to planes being flown into it. (I know, I know, the building isn't in the West, it's in "their" territory. But if the fundies decide the people who built this thing are trying to out-build the West, who knows.

So let 'em try. We'll see if it's still standing 10 years after completion.

captcha = grenade

As others said, pointless project ....

[King_TJ]

The fact is, we have no need for building this tall. If the Arab world didn't have more money from oil than they know what to do with, they'd never spend the money on such a project in the first place.

Many of our current skyscrapers have problems with unoccupied rooms/floors, as it is. You can try to recoup money on tourism - but that only makes so much sense. The higher the building, the more you've got invested in heating and cooling, electricity, maintenance, etc. etc. -- just to get the same tourist dollars the "other guy" used to get with his tall building that USED to be the "tallest one" before you beat him.

Carbon fiber technology is worth pursuing, so sure - this has some engineering and scientific interest. But realistically, no ... We've got plenty of space on this planet for people without resorting to these measures.

Forget the cable

[Anonymous Coward]

That building has 200 floors. How many times will the car have to stop to pickup or drop off other people on the way up?

ThyssenKrupp MULTI

[wasteoid]

Problem solved. http://www.thyssenkrupp.com/en...

Re:Have you noticed that all of these tall buildin

[dave420]

There you go again - any opportunity for you to throw in some casual xenophobia in a completely unrelated article, and you jump at the chance, showing us just how scared and little you are.

Your intelligence is about as high as your morals.

Up, up and away

[fyngyrz]

Hang a lighter-than-air balloon off the top of the elevator. If the balloon pops, the force is released from the balloon cable (which can be very short) and the brake engages. No counterweight or long cable required. Now you have the same energy requirements for lift (because the balloon is countering the weight of the unloaded elevator) and you can go back to considering how to create rack and pinion out of short rail sections (to allow for flex) plus power pickup of some kind (induction is an excellent candidate, because you can ensure that the energy pickups are very close to the sources during all operations. Fractions of an inch should be entirely practical.)

The only real problem is all of our bloody balloons leak. :)

Re:Up, up and away

[Noah Haders]

why do we keep trying to do induction as a power source, instead of using it as the prime driver? that way the elevator is just a big electromagnet, and doesn't need to house the motors.

relatedly, when are we going to break away from this notion of elevator "shafts"? I say give elevators the power to move up/down, sideways, and rotate. Imagine if an elevator was a big crawling robot that scaled the outside of the building, and every floor had exterior elevator doors. then everybody would get into a crawling robot and the robot would go to the right floor! That would be pretty sweet. I would call it "spidervators"

Tried and True

[Anonymous Coward]

Yeah, people. Rely on the tried-and-true. Don't bother thinking outside the box. Then you can avoid all of that testing and development of your ideas.

Let me guess - you're not a billionaire, are you?

40 years? No.

[fyngyrz]

Nor was the new testament written and compiled over 2000 years.
More like 40 years max for both.

The NT has appeared in many distinctly different versions. Bishop's bible, King James, and so on. Because of the nature of the source material (Greek, Latin, Aramaic) the act of translation is prone to producing differences. The "modern" versions often read quite differently.

For instance, Matthew 5:18:

King James: For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.

God's Word: I can guarantee this truth: Until the earth and the heavens disappear, neither a period nor a comma will disappear from Moses' Teachings before everything has come true.

New Living Translation: I tell you the truth, until heaven and earth disappear, not even the smallest detail of God's law will disappear until its purpose is achieved.

...and so on. And that's without the various doctrinal interpretations that vary over the years and the various people who further interpret the text to others.

Those differences can be huge. The context of the above is with regard to the continued relevance of the laws of the old testament. Jesus (the speaker) says that until heaven and earth pass away (which I think we can go with "hasn't happened yet"), the law remains in place. But that doesn't stop entire Christian sects from trying to claim that the OT has been superseded in its entirety by the NT.

Why use a cable?

[Anonymous Coward]

Yes it is as follows. If you use direct methods of transferring the energy to the walls such as a lead screw. You get about 50 more power for acceleration. However you get to use energy to keep the speed up because your constantly working against the force. The lead screw is almost otherwise identical to the track except you dont need to carry the engine which is just dead weight.

The counterbalance system needs more energy accelerating. BUT here's the big deal, keeping constant speed is nearly free of charge. So wile you can not wind the inertia accelerating the counter balance makes the elevator really really energy efficient. Furthermore the system has less friction to overcome than the track or lead screw system.. The system is also pretty balanced in power both ways.

So technically a linear magnetic rail MIGHT be better IF and only If the elevator constantly accelerates and your only moving in one direction up/down. But its ghard to say im still in the middle of crunching the details here as its much harder to get hold of the exact pieces of data. The others are easy enough to calculate and their difference is manly in the gear size and max acceleration/ constant speed energy consumption.

Lunar Elevator?

[WindBourne]

It would be interesting to see if this could work for a lunar elevator.

Re:Have you noticed that all of these tall buildin

[Chrisq]

There you go again - any opportunity for you to throw in some casual xenophobia in a completely unrelated article, and you jump at the chance,

On the contrary people are staring to realise that Islam is not the religion of peace, and is a real threat. There were probably people like you saying "Nazis are not all bad, they just want to get on with their lives" before WW2. The thing is that both Islam and Nazism are ideologies that drive their followers to dominate and destroy others. When the Muslims in the West rise up they will try to do exactly what they say the will. Remove free speech, freedom of religion, equality in the law - in short implement Sharia.

showing us just how scared and little you are.

Have you noticed how often I get upvoted now? a er back I only got thumbs down. People are starting to realise the truth, and those who love freedom and equality are not scared but angry.

Your intelligence is about as high as your morals.

Well thank you.