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Tram Team (Pferdebahn)

Started by jameskuyper, February 09, 2013, 03:15:08 PM

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jameskuyper

I'm running version 111.0. In pak64, between 1865 and 1960, a tram depot will show only one Locomotive: a Tram Team (Pferdebahn) with a max speed of 25 km/hr, that cannot, itself, carry anything. It seems to me like the retire_year should be earlier. Until 1932, it can be connected to a Tram Wagon (Pferdebahnwagon). But for three years, there's nothing for the Tram Team to pull. After 1935, if the Depot is electrified, it can also be connected to a Bennhardt T-26 electric (Lowa), but that car has power sufficient to go 50 km/hr and can carry passengers – so what point would there be in connecting them? It turns out there is one:  The electric engine alone can pull no more than 11 fully-loaded Bennhardt T-26 cars (Lowa_Anhaenger), at 6 km/hr  (31 km/hr empty). Adding a Tram Team raises the fully loaded speed to 15 km/hr, but drops the empty speed to 25 km/hr. This works because the Lowa has no Constraints.

asaphxiix

The horse tram staying too late is probably a mistake, but it shouldn't matter to you - no reason to use horses trams after 1900 anyway. If electrified trams only appear in 1935, then the trams require more work to introduce steam trams or early electric trams before the turn of the 19th century. I actually started doing this for pak 64 experimental. Also I think it would make much more sense for a tram convoy to be limited to one car (or two at max) , as in pak128 uk.

Ters

Lots of trams have more than two cars. I don't know how often two-car units ran coupled together. Technically, they probably could, but perhaps more for salvage and transport.

asaphxiix

#3
well, I'm guessing this is a terminology dispute that's probably as old as the game itself... Personally I like the distinction between tram (streetcar/trolley) - short convoy whose rails are mostly on the road; and a light rail - longer convoy, rails off road (parallel to, or distant from the road, or partially underground). but I realize this isn't a very clear distinction, and also that light rails are often on the roads as well. In Lisbon for instance there are two kinds of trams - the older tram going on the hills, with just one (very old and slow) wooden car, and the newer light trains which are actually articular long single cars (also runs on the roads mostly). So these more modern cars could be sold as single cars of greater length, perhaps 2 tiles.

And also, it's quite hard in game-play terms and not very realistic, I think, to make an urban line using the road system with more than 2 tiles stop length. Also, it should be less modular, since such longer trams are usually articular, and they are more recent. Classic trams, especially of the early 20th century were and still are short cars.

I'd love to discuss more on this subject with examples.

http://en.wikipedia.org/wiki/File:Flexity-Outlook_Alicante.jpg (light rail, aside the road but not on it).

yoshi

Under the German law, tram length is limited to 75 meter.
http://www.gesetze-im-internet.de/strabbo_1987/__55.html
Considering the number of German contributers and players,
it's not a good idea to limit the tram length shorter than this 75 meter (i.e. 4 x 18 m car) limit.

asaphxiix

The question is, have there been in fact trams of 75 m length? It seems the world record for the longest tram belongs to the Combino in Budapest, of 54 meters.

But I think this isn't really about restricting the length, but more about planning the cars, considering economics and physics, and according to the features of each model. For instance, it makes no sense for two horses to be able to carry more than one car of reasonable size and weight (for 19th century trams). As to electric units, those also are usually not modular as trains are. The Combino is an exception, and indeed its length (and width) may vary greatly. But most modern trams come as units of a long articular car, not as separate cars you can assemble as you please. So perhaps it would make sense to unite some of these models (I'm not very familiar with the real life basis of the existing models in the pak T13 T24 etc.) into complete units, which may be of different lengths, 5, 10, 20, 30 meters etc. and have different speeds weights and capacities.

Another issue is how is length defined? How many meters is one tile? At least in simutrans experimental, this usually varies between 100-250 meters, so a tram should never be more than one tile. But then, scaling is far from perfect in simutrans. Still we need some sort of basis.

yoshi

I know more than 10 examples of trams longer than 54 meters.

The longest tram I know is the 100 meter long tram in Hannover,
which consists of 4 units of TW 2000 or TW 2500 articulated tram vehicles,
although such long trams are used only during major exhibition periods.
Usually, their maximum length is 75 metres, consisting of 3 units of TW2000 or TW2500.
http://img360.imageshack.us/img360/2901/1150087dl.jpg

In Stuttgart, two DT8 2-section-non-articulated tram vehicles are coupled on some routes, which length is 77m.
http://img354.imageshack.us/img354/6781/dsc00272bh.jpg

In Mannheim/Ludwigshafen, two 5-section-articulated trams are sometimes coupled, which total length is about 58 m.
http://www.bkcw-bahnbilder.de/PictureGallery/pix/de/tram/mannheim/601-650/621-630/621/mvg621_bk0805040020.htm

According to a Hajo's old post, one tile is 50 meters,
but tram vehicles in pak64 are larger than the scale.
Hence, you can assume that one tile length is around 30-40 meters.
Considering that, I think at least two tile long trams should be allowed.

Ters

I don't think Simutrans should enforce a length limit in terms of meters or tiles. The existing constraints should be used, but might need to be improved to disallow infinite repeats of vehicles. This is not only useful for trams, but also normal trains and road trains. Yoshi's picture shows that two DT8 units can and is coupled together, so attaching a second "driving" unit behind the first "trailer" must be allowed, but the current rules can't make a distinction between what is allowed behind the first trailer and the second trailer, third and so on. A hack would be to make the second "driving" unit a distinct type of vehicle, but this becomes less and less practical with increasing number of legal repeats. Multiple-unit train control seems to be limited to two or three vehicles or sets on those vehicles/sets I've heard details about.

greenling

Hello
The new Siemens Avenio can get a Length from 72 meters.
here a Photolink:
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Ters

I find it hard to call the longer versions trams, but it shows how gradual the transition from tram to light rail is. It is also a gradual transition from light rail through metro to normal rail. Therefore, it won't reflect reality if Simutrans makes a clear distinction.

wlindley

Perhaps such trams could be coded in Simutrans as follows.  There are four types of sections in common to all the designs shown:

       
  • A powered driving (leading/trailing) end unit with cab -- let's call this type A;
  • an unpowered end unit with cab -- B;
  • a powered center unit -- C;
  • an unpowered center unit -- D.
The Siemens Avenio trams shown are thus, from top down: AB, BCA, BCDB, BCDDB, BCDDCB, BCDDDCB, BCDDDDCB.

The Hannover trams shown are BCDDCB; the Stuttgart trams are simple but rather long AB pairs; and the Mannheim trams are BDCDB.
Thus, you can start building a tram either with an A or B section; after either of these you may add C or D sections, but you must end with an A or B section.  Without at least one A or C section, the unit is not powered and cannot drive.  An insufficient number of powered sections can be built, but results in a unit with poor performance.
Those restrictions can all be easily coded into Simutrans's constraint system. 

Users might make some non-prototypical designs, but you could probably actually order real ones from the manufacturer in almost any combination.  And oddball configurations are what give our individual cities flavor.

Ters

How does that allow ABAB, but disallow ABABABABABAB?

wlindley

Quote from: Ters on February 10, 2013, 08:59:21 PM
How does that allow ABAB, but disallow ABABABABABAB?
Is there any technical reason, beyond the capacity of catenary electrical distribution systems, why a city could not build a railway capable of hosting twelve-unit trams?

Ters

As a wrote earlier, the multiple-unit control systems seems to often have a limit at three sets, regardless of the number of cars, at least for trains. One can get around that by only linking the sets mechanically and putting a driver in each, but then you get the difficulty of coordinating the drivers. This is probably only worth it as a desperate attempt to increase capacity on a heavily congested line.

ӔO

Probably, the easiest method would be to increase purchase and running costs of an ABABAB combination, over a BCDDCB combination. Driving units always cost more than equivalent trailer or motor units and CD units ought to give more capacity, compared to their length, over AB units.

Then players would be less likely to run AB*n combinations. It's a game, so if the player wants to run such a combination, let them do so. I'm quite sure most players would rather choose a purpose built combination that is cheaper and holds more over a somewhat comical AB*n combination.


IRL, the only reason why you see some 'strange' usage instances, is because the company that operates it is short on money to buy a proper, dedicated unit.
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wlindley

#15
Quote from: Ters on February 11, 2013, 05:45:56 AM
As a wrote earlier, the multiple-unit control systems seems to often have a limit at three sets

With today's computer controls, that is surely no consideration.  And this seems to have been more an operational rule than an electro-mechanical one.

Boston MBTA did operate three-car trains of 1940s-era PCC streetcars from the 1950s through 1986, and I did ask George Sanborn, MBTA librarian, how many cars could operate together; he said they often operated much longer trains when pulling "dead-heads" to the barn.

Certainly the New York Subway, for one, has operated twelve-car trains, admittedly of a heavier design, but consisting of six two-car married-pair sets, for at least seven decades now.  MU technology of the 1940s was clearly capable of six-car operation.

I suggest the three-car MU limit was due to considerations like station length, the length of city blocks in which trains might have to stop, and the practicality of ensuring safe door closure. 

For the game, AEO's comments about higher costs for A units, and the performance trade-off of the powered/trailer ratio, seem to make an arbitrary limit on tram length unnecessary. Let the user decide to put all powered units on a hilly line (like San Francisco), or many trailers on a long flat interurban line (Chicago Terminal Railroad ran both express trams and steam trains on the same line, blurring the distinctions between "streetcar, light rail, and heavy rail" in today's terms)

Ters

Quote from: wlindley on February 11, 2013, 01:03:50 PM
With today's computer controls, that is surely no consideration.

Why do people always think things get easier with more modern computer systems? To me it seems to be exactly the opposite. Apparently the new FLIRT trains in Norway support up to three sets. Double sets are working fine, but last I heard, they were having trouble getting three sets to talk together. The number of cars isn't the problem, but the number of sets of cars in a "super-set".

Quote from: ӔO on February 11, 2013, 08:23:33 AM
Probably, the easiest method would be to increase purchase and running costs of an ABABAB combination, over a BCDDCB combination. Driving units always cost more than equivalent trailer or motor units and CD units ought to give more capacity, compared to their length, over AB units.

What if there are no C or D? Such flexibility is relatively new, isn't it? Considering we started out with horse pulled trams here, we should also take older models into consideration. My impression is that during most of the 20th century, you got fixed sets of A, AA, AB, BCB, ADA or ACA, that in some cases could be coupled together into bigger consists. Some law limiting the length of vehicles driving in the streets might have prevented consists from growing infinitely long in real life, but imposing a maximum length for the tram waytype in Simutrans might be to harsh, as the waytype is also used for light rail. A pak set can also contain vehicles from different regions with very differing limits. Then there's any technical limitations, which also affects trains.

ӔO

yes, such flexibility is relatively new. Most trams were either AA or AB up until 1990 or so.

It's best to look at it as a problem vs. solution scenario.

From 1900 to around 1960, there shouldn't be as many pax moving around, and there should also be good competition or support for tube/subway lines. Buses may also be inadequate in early 1900's.

From 1960 onward, you should have more pax to move, but an increase in construction costs of tube/subway lines. Since it can be expected that the tube trains have grown in length, an extension to the line may be over built for its purpose, so as a cheaper alternative, you get longer trams and LRT.
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greenling

AEO
No, From 1900 until 1960 have Trams many pax.
After 1960 break the pax transport per tram in.
And in the year 1990 have then beginn to grow the pax transport at tram again.
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Working on a big Problem!

wlindley

There were always oddballs.  In the terminology from the above post, here's a Boston tram of type ADA circa 1913



A very early articulated A-B prototype was built for Cleveland, Ohio in 1893:



but at least in the USA, 1913 is about the earliest any system seems to have operated anything articulated.

In the game, I would imagine that until 1910, only single units and single-units-with-trailers would be available; then A-A / A-B articulateds would start to appear, but not able to be M.U.'d together; followed by increasingly complex possible  combinations.

As an example, In the dat files this means for circa 1913, defining "A-front, A-back, B-back" units where A-front must be followed by either A-back or B-back, and nothing else could be built.  Circa 1920, "A-front, A-back, B-back, C-center, D-center" where A-front must lead, and be followed by any non-front unit; and any center unit must be followed by any center-or-back unit.  Circa 1930s, a back unit can also optionally be followed by a front unit (simulating M.U.)  Adjust the decades depending on your city.

greenling

Woh Wlindley
That are very old trams.
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