A thought experiment:
You’re now the owner of the world’s largest cable gondola transit manufacturer on the planet. This could be a fictional company or a real company; it doesn’t matter.
You’re told by your CEO that three (and only three) innovations must be developed to ensure the technology’s viability into the future. One innovation needs to be relatively simple; the second innovation needs to be difficult but manageable in the near future and; the third innovation needs to be a pipe dream – something that’s likely never to happen within the next decade, but that would nevertheless improve the product drastically.
Your CEO asks you what those three innovations should be.
Here’s mine:
- Reduce dwell times to under 30 seconds – should be relatively simple.
- Develop gondolas that can operate at the maximum speed of aerial trams – with time it shouldn’t be a problem.
- Allow for off-line stations such as those found in faux-prt systems – unlikely to occur anytime soon.
What’s your answer?
36 Comments
“Allow for off-line stations such as those found in faux-prt systems – unlikely to occur anytime soon.”
Could you explain that a little bit?
That’s my question too. Today, gondolas can be taken offline and put into storage. Why can’t that be done in a station?
I don’t see a problem there either. I’ve seen some of those offline storage units and how they disconnect from the main cable. The “disconnect from main cable” appears to be simple and mature with gondolas, yet is currently one of the “big hurdles” for PRT (switches in the mainline vs. safe stopping distances). Once a gondola is off the mainline it’s typically moved by overhead drive wheels (ignoring manual systems for this case) which can move them among any low-speed switches safely. A gondola system like that could even have full-stop boarding bays with their own platform doors, as seems to be the trend for unattended APMs.
By “off-line stations”, do you mean stations where some carriers slow to load and unload passengers and others go through at or near line speed?
If so, I can think of two potential ways to do that. One is to detach all the carriers, but route the express ones to a track that goes through at line speed, and the locals to one that slows the carrier to station speed. This would require either the local or express carriers (or both) to take an S-curve at line speed, which probably isn’t much of an issue: I used to regularly ride the old Sugarloaf, ME gondola which went through some S-curves in its midstation to get around the drive machinery and bullwheels, and did so at nearly line speed, which was slower than modern gondolas but not by much. (It was an old manual system with no drive wheels; the midstation was only used when it was too windy to run the summit stage.) This would also work with an angle stations if it’s not that sharp an angle.
In theory you could also simply not detach the express carriers, by moving the decel/accel wheels and detach rails out of the way , and having the local carriers take an S-curve. In either case you have to move some big parts in between carriers, requiring appropriate interlocks so the lift can be stopped if something jams.
This is almost exactly the list I thought of while reading the question. For #2 I’d specifically request a top speed of 40 mph (64 kph). There are just a lot more scenarios where it becomes practical if you can have gondolas move between 20, 30, and 40 mph lines depending on the distance to the next station.
For #3, I think it would be enough to have some cars stop and have a queuing area for cars behind them. Passengers would press a button when they want to get off at the next stop, people waiting at the station would also have a call button, but when they press it, rather than stop the next car it stops the third car unless a sooner car was stopping anyway. This would prevent bunching. The busiest stations and terminals would be designed to stop every car.
So do these modifications flip the order of 2 and 3?
I agree with the top speed being crucial. There are a several situations I can think here in the Philippines where a long distance Gondola system would be ideal to link a proposed high speed rail line along the coast to a city +- 30 km away and up to 5,000 vertical higher. It would be faster than a bus or car and eliminate the nausea inducing switch backs. Unfortunately the current speeds would not make this practical. Of course by the time something like high speed rail happens in the Philippines the cable technology will probably be ready.
Remember, however, that station size becomes a factor in top speed (for detachable systems). That could impact things.
Here’s mine:
*1 Give gondolas a proper face.
*2 Make stopovers (‘stations’ with extremely small footprint)
*2 Stop making connections, start building lines
*3 Gondola on demand (no waiting lines, no empty gondolas “hanging/flying” around)
You might say: we already got point 1 and the second point 2 – I am assure of that but I wrote it for a reason.
“One is to detach all the carriers, but route the express ones to a track that goes through at line speed”
Exactly, like there is no stopover it would just have to go straight and for those cabins stopping, maybe they would need a system to detach at line speed but not doing the S turn.
Can you imagine a grip on top, which is not just connected to the tracking cable but also has a connector to the other side? And the other side has some preparation for something like rails and it just takes that cabin away that all the others can pass?
Of course the software has to be more complex than it is today, because those cabins need to get integrated into a line again, but that should be manageable.
First innovation. Fire any CEO that thinks he can limit innovation (to just three).
Second innovation: get Maggie Thatcher to run it. She will sell it to highest bidder and require a $100 million performance bond. New system then becomes innovation-driven. New CEO makes base pay of $1/yr and. For every rider system looses, he/she pays $10. For every rider gained, he/she makes $10. Each route is individually-privatized. Read Forbes two years from now: “Transit’s New Billionaires”.
Make it personal. Meaning small cabins. With heat/AC, wifi, TV, coffee makers.
Make it on-demand. Easily done. Google patent database and you will find several cable/rail examples of existing ‘art’ that could work.
The pipedream? Make it dual mode. Meaning something you can drive to/from your suburban home to a guideway station located on outskirts of city. Since the drive train (wheels, motor, battery pack, etc.) is the heavy part, the pax pod will separate from the drive train, which will self-park. Your pre-programmed pod will now take you to work (which means probably ‘slipping’ two or more intersecting cables), you step out of pod (station integrated with your workplace) and pod is integrated into the system (or if you can afford it, parked at a convenient location outside the urban core). Returning home is the reverse: you hop a pod and seven minutes later are at your destination. Pod re-mates with another drivetrain and off you whir home. If you want, it even drives you. At your home, since it is inductively charged, you don’t even have to plug it in. This is not a pipe dream: it WILL happen. Coming to a guideway near you.
My take on it is (pretty much the party line here?) that presently there is nothing missing from the technology. It’s only understanding of the technology that is missing. Like the Medellin and Caracas ones they need to be integrated into an existing metro or metro like system in a European or English speaking part of the world. If it happens in Japan or South America it is almost invisible. Integration happens physically with the metro station or bus station platform or whatever, is co-located with the gondola station. And integration happens with ticketing. i.e Tag on – tag off type contact-less smartcards. (If Paris’s Montmarte Funiculaire was closer to a metro station then it would be more obvious to more people, so that’s a shame.)
Contrarily to Dave above, they’re not going to make billionaires out of gondola travelling. The business models will be old school and with fare recovery and subsidies like other transport modes there’ll be modest and safe returns on investment, and much investment will be by municipalitites or transit companies rather than gee-whiz venture capitalists gambling pension funds on ponzi schemes. And as for the thought of the ghost of Maggie Thatcher, urrrgh I better go listen to Elvis Costello’s Tramp the Dirt Down on Spike to redeem myself.
My take on why aerial gondolas aren’t more widely used in terms of urban transport are that they are the icing on the cake. A backbone of heavy rail or light rail may have been built, and it may be reasonably useful in itself carrying 15% of all commuters, with another 20% on slow buses, and the rest are by car. The rail system is the cake. A dozen aerial gondolas reaching out from the rail stations to other places within the city widen the footprint immensely and would change the figures to 25% rail, 15% bus, rest car, but that is a hard sell. First you’ve got to get over the unfortunate bone-headed conservatism of those in power (who may have an ideological problem with funding PT at all, definitely the present case in NZ at the moment) and the rail system only begrudgingly gets funding because its inherited from history, or it’s begrudgingly supported because there’d be an outcry from some parts of the population if it was to shut, or for practical reasons in that the gridlock is already bad, and would only get worse. Then to come along and say we want the icing on the cake and we want to make the train system more useful by building aerial gondolas. They don’t understand, or would think “but we already have a working system.” Gondolas are small scale, and they work for foot and (at a pinch) cyclists. They don’t work for motorists. No one is ever going to demand a 1,000 space park and ride outside a gondola station. Gondolas encourage people to walk on their legs and to leave the car at home. A lot of people have forgotten that that is what their legs are actually for, and for decision makers who drive their Mercs to their subsidised parking spot and sit in their office in the office tower, they have definitely forgotten.
So my take on it is that perhaps aerial gondolas should be marketed as things that train stations need. A train station needs passenger shelters, clear signage, real time electronic signs, ticket gates, ticket machines, park and ride, secure bicycle storage, bike share scheme bikes, and aerial gondolas to integrate it into it’s neighbourhood.
And perhaps one thing the Gondola Project could do is have a stock of real world examples of where it makes sense to build such gondolas.
Interesting and true, Matt. But those weren’t innovations, those were things that are missing – and don’t get me wrong: you are abolutely right and this is exactly what needs to be done first.
Any ideas where those real world examples should be build?
My answer: „All details are simple to solve !“
It is no problem to reduce dwell times under 30 seconds, it depends on size and capacity of the gondolas and how many passengers have to enter and get off at this time, the next gondola you can enter arrives in 12 seconds, isn’t it?
Aerial trams accelerate and brake outside the station, detachable ropeways inside the station. According to braking distance and distance of acceleration the station must be long and longer, and THIS is the most limiting factor.
Cable propelled gondola Systems just have only to be faster than traffic beneath. Faster velocities make sense, if the distances between the destination stops are wide and you have enough time to use these faster velocities (to save time). But at urban systems with smaller distances you don’t need a fast velocity ! Time you save at a fast subway, you waste at the footpath to reach this subway, so you can travel with a slower transportation and in sum it’s the same time.
If gondolas have to be stored at each destination stop, you can start from any station. What is the problem?
Hi (CEO-)guy, read better my guidance at:
http://www.abcde-institute.org/urban_ropeways_destination_stops.html
“Faster velocities make sense, if the distances between the destination stops are wide and you have enough time to use these faster velocities (to save time).”
Even if distances between stations or stopovers are short faster velocities and faster speeds still make sence. Only stations must be able to handle them. If you are fast at 10 stations you’ll probably reach your destination about 3 minutes or 5 minutes earlier.
But you are right, that will influence the station and its length.
“Cable propelled gondola Systems just have only to be faster than traffic beneath.”
Yes, at its best. But if they will show the common advantages of travelling with this kind it’s driverless, jam-free, more sustainable and so on -> cheaper and still pretty good.
A possibility to make gondolas faster would be to operate it on the ride between the stations like a Reversible Ropeway = Aerial tram AND make it detachable in the stations to move it to the next rope (with separated drive). But at this theoretical system you need larger gondolas, because there are only one gondola on the way in one direction between destination stops. And you need more time at the stations for entering and get off from larger gondolas and the gondolas must leave exactly on time and the distances of destination stops have to be the same. Too much complicated.
I think, a velocity more than 4 m/s is not practical (legth of the stations, etc.).
Guenther,
I believe 4 m/s is 14.4 km/h or less than 10 mph, I’m pretty sure they’re faster than that.
I think your detachable aerial tram idea is close to right, but the switch from the acceleration rope to the constant speed rope will not happen at a station, it will need to be built into some tower near the station, so there is an acceleration zone where there can only be one gondola at a time, and then you switch to the main high speed rope which can hold lots of gondolas, then they reach the deceleration rope which can only hold one gondola at a time.
LX, merging stopped gondolas and high speed gondolas would be tricky, but I could see having a high speed limited stop line above a normal speed local line.
#eric :
No ! You need for braking to the destination stop and then accelerating to the rope a riding length of the road way.
With -1 m/s² (stop and then) 1 m/s²:
to 7,5 m/s you need 66.3 m (braking distance and accelerating distance)
to 6,0 m/s 46 m ( – ” – )
to 4,0 m/s 26 m ( – ” – )
At start or stop stations You need only half the length.
But at stations to “ride through” you need full length.
You think, you can build a destination stop with a length of 66 m in town ??? Or several stations…
You need shortened stations, I described here:
http://www.abcde-institute.org/urban_ropeways_destination_stops.html
(Scroll to the third schematic image there ! )
To mix a Reversible Ropeway accelerating system and detaching the gondolas at the stations is too complicated for handling. Forget it.
… if yo brake and accelerate INSIDE the station !
Number 3 for me: change planning rules to reflect the fact that the world is now more urban than rural and we need to curb rampant burbs-loving nimby individualism in favour of wider societal benefits. This should drive down the cost of building out public transport.
@ Original David,
Agreed, but with two caveats:
1. This doesn’t really have to do with cable does it? 🙂
2. While agree with the need for an emphasis on the greater good rather than oftentimes selfish individualism, I also recognize that we’re talking about humans here. And humans are oftentimes selfishly individualistic. And that’s unlikely to change in the future. One thing I’m pretty passionate about is recognizing this fact, and finding ways to work around that issue to affect change rather than try to change those people’s worldview.
Guenther,
I think you misunderstand what I am suggesting. Say we have a line, and the line has two stations which are separated by 1 km or more, likely much more. We want to go 15 m/s just on that one link — elsewhere we’ll be slower, and if the stations on either end of that link are pass-through stations working by your design or mine, gondolas passing through those stations will not be travelling at 15 m/s, they’ll be travelling at 2 or 4 m/s.
Using your suggested 1m/s^2 accelleration, gondolas take 15s and 112.5 m to accelerate/decelerate. The stations won’t be that long. What I am suggesting is, when a gondola leaves a station, it is attached to an acceleration rope. Only one gondola at a time can be attached to this rope, meaning gondolas are more than 15 seconds apart; the station will make sure of this. Once on the rope, it is working like an aerial tram, accelerating outside of the station because the line it is on is accelerating.
112.5 m away from the station, probably built into a support tower, there is a mechanism to switch each passing gondola from the acceleration rope to another rope that moves at a consistent 15 m/s. There is no limit to the number of gondolas on this rope, other than they will be spaced at least 15s or 225m apart. The gondola will travel a kilometer or more at this speed, then it will at some other tower be switched to a deceleration rope which will slow it down to enter the next station.
A fascinating idea !
If a gondola brakes, the brake-rope decelerate from 15 m/s to 1 m/s.
The gondola is at the station.
The brake-rope accelerate to 15 m/s to brake the next gondola.
The same on the other side to accelerate the gondolas.
The same accelerating/decelerating rope for both could be a little difficult.
Why not?
A problem is, you need a tower to return the accelerating/decelerating rope.
I don’t believe, that a ropeway can pass a tower at 7,5 m/s or faster. Because this speed is, I believe, the maximum speed between 2 stations without tower. We must ask the manufacturers.
To hang the acceleration rope to the next station is not a solution, because you have:
2 track ropes carrying the gondolas and the traction ropes by cable carriers,
one tension rope to drive the gondola at 15 ? m/s,
the empty tension rope back (you need different drives for every direction at urban ropeways,
one accelerating rope to accelerate the gondola,
and the same rope empty back,
one decelating rope for the next station,
and the same rope empty back.
So the 2 track ropes have to carry the gondolas and 6 ropes at one direction. Very expensive.
@David:
Yes, the “world” may be more urban than rural, but the city-central traffic I’d mark as a completed issue. Meaning most cities got their infrastructure working, maybe some have needs to make them more efficient, but all in all that thing is solved.
Now on the other hand connect urban area with suburban and rural, that’s the important factor.
In a central zone the catchment area for a bus/tram is about 300m and for metro 600.
In an urban area for bus/tram 400m and for metro 600m.
In a suburban area it is for bus/tram 600m and for metro 1000m.
So besides suburban area… what is there? Rural. In order to prepare our cities as well working cities I think it is more important to look a little deeper into the rural aspects of this topic than the urban.
Trains can be doubled, pulsing can be increased, but rural stays rural and those areas should get connected.
Just one example I know about: Frankfurt in central Germany doubles the size of its population every morning and halfs it in the evening. From around 600.000 to 1.200.000!
@Guenther:
7,5 m/s over towers is absolutely possible. A few 3S-systems are doing it right now, aerial trams can even go much faster than this, but as you said: just between the towers.
I was looking at the sketches on your page and read what Eric L and you supposed.
As much as I like that idea you have to provide the mechanics to make that switching possible. I went through a couple of ideas during research, but having a schematical plan is nothing without the sectional drawing and what is more important is the technology, that allows the grabbing from an acceleration rope towards a hauling rope – and even switching tracks.
I really would like taking a look into the sections and switching technology/mechanics you were thinking of.
#LX
“but having a schematical plan is nothing without the sectional drawing and what is more important is the technology, that allows the grabbing from an acceleration rope towards a hauling rope – and even switching tracks.”
??? I have no schematical plan on my website about a system, “that allows the grabbing from an acceleration rope towards a hauling rope – and even switching tracks” ???
Do you confuse the issue?
@ Guenther,
There are no “acceleration ropes” in current systems – at least not the ones I’m familiar with. Vehicles are accelerated and decelerated by a system of wheels.
Guenther,
Assuming the line speed rope needs to run all the way to each station, then for stations 1 km apart you need the same hauling ropeline you’d need for a regular gondala, plus 112.5 m for each acceleration and deceleration zone, and the two directions there have to be separate loops, means you have the same amount of hauling rope as in a 1550 m gondola (and the same amount of suspension rope as a 1 km gondola). Ropes are unlikely to be the primary expense in an urban setting, and the situations I’m looking at where I’d want 15 m/s speeds involve distances of 3 km or more. I’d be surprised if the additional 550 m of hauling rope added even 10% to the cost.
However, I suspect the issue of top speeds over the towers is a very real one. But 7.5 m/s exists now, and if you could spend 6 times as much on towers on one segment to double that speed there are places where that would be worth it. Now if that requires the sort of redesigns that would make towers more expensive everywhere on the line whether or not gondolas were going fast at that particular tower, then that’s an issue.
When you’re designing for ski resorts, people aren’t in a hurry and couldn’t get around faster anyway. I don’t know how much manufacturers dream about ways to make their product more expensive to make, but if you can confine the costs to the segments where you get a lot of benefit from that cost, then that improves the flexibility of the technology and means it’s useful in more urban settings.
@ Eric L,
“the situations I’m looking at where I’d want 15 m/s speeds involve distances of 3 km or more”
I think that’s an excellent point. High speeds are only important in situations where the distances between stations are great. There is absolutely no reason to push the technology’s upper speed limit except in these exceptional situations.
Furthermore, as you point out, stations along high speed lines will necessarily be longer to the point where they would be inappropriate in a dense urban area.
Are high speed gondola systems something we need? Probably. But only in very specific situations.
You can save a lot of money, if you reduce the number of towers and the optimum is, that a gondola rides from station to station (destination stop to destination stop) without any tower, about max. 600 m (so you have a footpath of max. 300 m to the next station).
You need 2 VERY expensive towers to return the acceleration / deceleration rope, you need more energy,..
Fast gondolas can drive with 7,5 m/s but it is not often in use, only you have to transport large crowds (of winter sportsmen and -women). The same ropeway moves most of the time with about 4-5 m/s, it saves energy and money.
The ropeway only must be faster than the speed of the car jam beneath.
I have asked a manufacturer:
7.5 m/s or faster is no problem at towers.
But legal provisions of different states prohibit speed faster than 7.5 m/s.
(and some legal provisions prohibit stations without observing personal).
We must modify some legal provisions too to endorce urban gondola transit…
@ Guenther,
In the United States, the manufacturer can set the upper limits on speed.
Also, from a riders perspective, unmanned stations would be a bad idea.
sorry, to enforce urban gondola transit…
Great discussion. My #2 (or maybe #3) would be: develop operator-less stations. Elevators were added to most buildings only when you didn’t need to pay an operator to stand there all day. They also became safer when automated. This would give gondolas a very strong benefit over most other transit systems, in that you’d dramatically reduce your operating costs.
I’d like to add one thing : take angles at pylons with normal speed.
Here’s mine:
1) The manufacturers have to design a “primitive” low-cost standardized intermediate destination stop, lowering the gondolas to pedestrian level, with a garage/emergency siding for 2 gondolas, that can built/sold/used hundred times in the same manner. And all traffic changing stations (gondola to subway to railway) are optimized to reduce long walking paths. With deposit boxes at every station (for purchases, heavy suitcases, bicycle helmets)
2.) The manufacturers build a fully automated system to move and operate gondolas inside a station or garage without wearing parts.
3.) Somebody develops a software system, where I enter my reservation with my data (start location, start time, final destination) so I order all my traffic vehicles (one hour) in advance and, changing from gondola to subway and from subway to the next gondola, I have a reserved warm seat at every time. So I don’t need a car any longer.