I Designed a Better Low-Floor Tram

[@Sp4mMe]

Talks about why fantasy transit maps can be a problem. Designs a fantasy train. Well played. Well played indeed.

[@RMTransit]

I don't really think it's fantasy to have a high capacity train to serve these various lines to be honest!

[@RMTransit]

@Tigger Official I actually need to get my rolling stock company started

[@ARod4374]

@@RMTransit If you actually do hit me up; I'm an electrical engineer with experience doing the sort of big power systems you'd use for train propulsion, an inveterate trainfan, and an avid 3D modeler. Also, as far as motors are concerned, there are tricks you can use (you can sling the axles low enough that getting them under the floor isn't too terrible, and if you use axial-flux PMAC motors on each axle you can get the motors small enough that you can package them in the walls easily; furthermore, you could probably use a structural design where you package the suspension elements in the corner posts of the individual units.

[@dzed468]

Came here for this exact comment

[@lovedfriend2020]

@@RMTransit I think Fort Myers, FL and Cape Coral, FL could use a light rail!

[@tomasbarbosa8654]

Your names for trains are good, but you still have a long way to go if you want to become like Stadler, the creators of the Kiss, Flirt, Wink and Smile! Great video!

[@RMTransit]

Stadler better watch out!!

[@dda40x]

Stadler were cowards with the "Smile", although it's definitely for the best. After Tango, FLIRT and KISS, the obvious name for their next big thing, their Swiss EXpress train, would have been… different.

[@georgobergfell]

@@dda40x 😁😁

[@offichannelnurnberg5894]

@@dda40x This is the reason why express S-Bahns don't officially exist in Schedules

[@phillyzfynest7]

@@dda40x lemme guess... the Orgy?

[@cityjetproductions]

The T1s on Vienna U6 already have this arrangement with the wheels at the edges, as do many 1990s German low floor trams, though only for the centre section. This is also a somewhat popular solution for retrofitting high floor trams with low floor sections (Tatra KTNF6, Gothenburg M31, etc). It does have some dynamic and maintenance problems though, especially if the wheels are steered.

[@RMTransit]

Oh yes the German speaking world always a step ahead lol

[@pixoontube2912]

Well, I think that Reece's design is good, but one has to consider possible noise. On MGT6D, the center wheels often start to squeal and its really annoying.

[@openlink9958]

@@RMTransit "German engineering is the best of the world!"

[@TramChris]

@@RMTransit You could even say the Germans are two steps ahead: In the 1990s, many german cities bought "MGT6D" trams, which have single wheels in the midsection. While the midsection of these trams is spacious and entirely low-floor, the technology turned out to be quite problematic to handle. A famous example is the city of Bochum, which got rid of all of its MGT6D trams because of massive technical issues. Also, riding in the midsection of an MGT6D is way less comfortable than in the front and back sections, which use classic bogies. So while being very popular in the 1990s, this technology basically disappeared in the early 2000s. Since then, most operators prefer classic bogies or multi-articulated trams with four wheels under every second car.

[@laurencefraser]

@@pixoontube2912 wheels squealing is general a function of the interaction between gauge, turn radius, and wheel-base, to my understanding. basically, if your corners aren't too tight for your gauge, and you wheels aren't too far apart for how long the corners are, you don't get squealing. Well, not if you actually maintain your trains properly, anyway. Of interest, every video I've ever seen of American trains on switches and curves is just constant squeal... but I've never heard a New Zealand train make any such noise, on video or in person. NZ noticeably has a narrower track gauge than the USA, among other things, and this held up even when, post privatisation, the company running NZ's railways was Intentionally running the thing into the ground (the aftermath of That mess is ... interesting... )

[@matthijspw]

Single wheels spaced far apart will have a larger angular deflection in a curve of a given radius, giving more noise and vibration. If you start putting single wheels on multiple consecutive sections you start running into trouble with degrees of freedom. the whole system becomes too constrained. More noise, more vibration. You also lose the self aligning properties of standard train wheels. There is a reason bogies are normally used.

[@gobyrail]

Spot on. For the non engineers in the room, larger angular deflection means more wear on the wheels and the track, more noise, and a much higher risk of derailment on tight curves (which effectively means the tram won't be allowed to run if there's tight curves on the system). The self aligning properties smooth out the ride quality for the passengers, so by moving to four fixed wheels instead of bogies you need to compensate with a much more complicated suspension system, which will add even more maintenance intensity and will take up space in the vehicle.

[@williamhuang8309]

What about articulated bogies where they are located underneath the gangways? Pretty sure the Stadler FLIRT uses that design?

[@matthijspw]

@@williamhuang8309 You will not get those low enough to get the gangway near ground level. The flirt has floors on 70cm height 9r so

[@lzh4950]

@@gobyrail Doesn't this sound like the design that Talgo has been using all this while too?

[@martinkominek6712]

@@matthijspw This already exists as low floor tram - Skoda 15T in Prague.

[@Steff2929again]

Škoda 15 T might almost do the trick. It's quirky and different, but also quite clever. It's the only 100% low-floor solution that isn't ridiculously over-engineered. It was introduced in 2009, so it's definitely time for an updated version. It would need wider gangways, and better suspension, but a lot of your wish list is fulfilled. It's somewhat expensive, but it's still a mystery why it hasn't been sold to more cities. Each section is quite long, giving large open floor areas. The Prague version is cramped with seats, but any layout is possible. There are two large doors per section. The Prague three section version is 31 m long, the Riga four section version is 41 m, a five section vehicle would be 50.6 m and so on. It uses Jacobs bogies between the sections. The motors are placed outside of each individual wheel, no internal space is wasted. 46.6 kW per motor gives ample power. The Prague version is geared for a maximum speed of 60 km/h, but higher speeds are possible. They can handle steep gradients. Individual wheel drive reduces wear on the tracks. The first and last sections have their bogies at the extreme end. There is no sweeping overhang, making the vehicles very agile, in spite of their size. They can handle very tight curves. It also improves the drivers' working conditions. Long-nosed trams are not kind to the drivers.

[@tommik1283]

I agree that 15T is a functional design but I would definitely change its rear section to high floor and populate with more seats (2+2 + full back) as trams nowadays also serve longer distances and "seated" back section would make sence. Definitely reduce the seats in the middle to just 1+1, the trams get crowded inside city and 2+1 causes jams. Driver's cab is way too large. Reduce that in favour of passengers. Outside design should be rework for more attractive appeal IMO. Also the idea of having just single cars eliminating the joints might be useful for some cities or night service. Or even designing motorized trailer cars that could be chained according to needs.... All based on this 15T design...

[@Steff2929again]

@@tommik1283 Anything is possible with this kind of unobstructed interior. The layout can be rearranged to suit almost any need. It's an open slate. Quite different from the usual low floor solutions where the interior can be somewhat of a labyrinth. I'm sure that a future update would include the exterior. Clients placing large orders can request their own exclusive design features. Most manufacturers will offer that service, albeit at an additional cost.

[@arnehurnik]

I'm actually wondering now why Jacobs bogies are not more common for trams.

[@Steff2929again]

@@arnehurnik Probably to keep the cost down. Many cities have opted for cheaper ways to get those highly sought after low floors. Increased maintenance costs caused by excessive wear on the tracks are often left out of the calculation. Procurement rules and offset agreement can make large public purchases seem quite confusing.

[@wsgthebg]

I think you have too many small segments, I would merge two of your small segments into one larger and put wheels between the segments. Having larger segments would create more capacity and allow more variations for seat placement between the doors. Trams have small segments for tight turns in narrow streets but lines that are built like a metro would in my opinion benefit from longer segments.

[@laurencefraser]

Remember, though, these things have to be able to (in some instances) corner within a road intersection (and similar situations), as I understand it. That puts a cap on segment length.

[@joriss5]

@@laurencefraser Some trams have segments up to 10 m long even on old networks (look at Melbourne's E and G classes). On more LRT-like systems (new networks in France for example, or the O-Train) there can be segments 12 meters long.

[@evocationist0420]

long segments with only four wheels each? sounds like the pacers...

[@JaneDoe-dg1gv]

How about jumping up to three-axle jacobs bogies between the segments?

[@Myrtone]

@@joriss5 Yes, about the same (it seems) as pretty much any high floor tram.

[@ZLDSmogless]

The London underground's Bakerloo line has pocket doors that slide in to the coach BERWEEN THE DOUBLE GLAZING OF THE WINDOWS

[@PeteS_1994]

The class 378 as well.

[@C.I...]

That completely defeats the point of double glazing. It needs a vacuum between the panes to act as insulation.

[@acceleratedsloth]

And it is always dirty

[@clawrence034]

@@C.I... I think in this case its so that you aren't catching people's fingers.

[@AMPProf]

Gosh all that for a door

[@alexandrutonita736]

The Frankfurt U5 rolling stock might be worth looking up. It is considered a Stadtbahn, akin to LRTs. Vehicles have two segments but some have no permanent cabs, meaning you can create a 8 car fully walkthrough trainset while still being able to service it in pieces.

[@noteworthy5911]

That looks neat! I'm wondering though how do you swap out the cabs + couple the articulated sections up to each other? Are there mechanical/magnetic linkers inside the edges and are they tedious to work with?

[@TorTheStone]

this looks exactly like Bergen(Norway)'s LRT, Bybanen!

[@RMTransit]

I know a good looking tram when I see one!

[@sjokomelk]

Which of course is a "Swiss" (German) Stadler. They know whats up.

[@Dinoteddi]

arent bergen's trams similar to the variobahns in London too?

[@sjokomelk]

@@Dinoteddi Yes. They were actually built for Bergen, since Stadler had some spare capacity in their production, and built them many months earlier than planned. And then TFL ordered the exact same model. So they just repainted them green instead of orange and sent them to London. And then built new ones for Bergen instead. That way they could deliver to TFL much quicker, and get paid quicker too.

[@TorTheStone]

@@Dinoteddi it is a variobahn made by stadler.

[@CopenhagenRailProductions]

Fun fact: The S-trains' bogies, was an experiement, done by Alstom and Linke Hofmann busch. This was done on an older S-train car of the "2nd generation", where one 4-wheel bogie was taken out from under the cab, and a single axle was installed, "driven around the curve", by a bar attached to the 4-wheel bogie at the other end of the same car. That led to the single axle design, that makes (AFAIK, after the UK Pacers have been withdrawn) the S-trains the only Multiple Unit in the world, to have single axles only. I simply can't think of other (currently in service) trains.

[@RMTransit]

Yeah which is super unique and cool! Because they are actually a really successful and good train model!

[@wasmic5z]

Talgo trains also use lots of single axles, but the powerheads on their trains still have traditional bogies for the driving wheels. The ULF trams from Vienna also only use 1+1 paired wheels, but those aren't connected by axles. I think you're right that the 4th generation S-trains are the only EMU's with all single-axle wheelsets.

[@kytkosaurus]

Unfortunately, there are still many Regionova (814) trains in operation in Czech Republic. And they are just that, DMU with single axes only. Created by permanent connection (and lowfloor section addition) of 810 motor railcars and the 010 trailers.

[@seatsea0]

I'd say that the trend is more towards Jacobs bogies, letting you keep the benefit of bogies but allowing lower floor trains and also making them more rigid in case of a derailment.

[@lzh4950]

Side note: Copenhagen's S-Tog's 4th gen rolling stock (the one pictured in this video @ 7:53) make similar sounds to Singapore's MRT (subway/metro) C651 rolling stock (the 2nd gen; which use conventional bogies though), probably as both models were made in the mid-90s & likely used similar propulsion systems (though the latter model is now being replaced by Bombardier/Alstom R151 stock)

[@tsguy-h3q]

Your RHCLFMT is quite amazing. Solving most problems that passengers have on such trams. That said, I think using smaller wheels with induvidual motors would greatly. help

[@RMTransit]

Yes I think it would need to use quite small wheels in order to fit everything in it would be complicated...

[@yrr0r244]

@@RMTransit I was thinking about small wheels too. And maybe even use different sized wheels. For the non-powered wheels, instead of one big wheel, we maybe can have 2 tiny wheels sharing the same load while taking less height.

[@laju]

@@yrr0r244 Wheels can't be too small. Small wheels tend to have problems in turnouts and crossings.

[@chrismckellar9350]

You will fine most newer Light rail vehicles (trams/streetcars) have a motor driving each wheel to increase passenger capacity.

[@tsguy-h3q]

@@laju Price of having a low floor system. If you're willing to spend more money, you can sink the trackbed at stations and run high floor trams, given you have a sufficiently large structural gauge.

[@RobinRense]

I was quite sceptical on your 'inproved' tram, and I still am. The main issue I have is your wheels: Wheels on all of your segments cause troubles while managing curves. You can read about that on Wikipedia about the Gelenk-Triebwagen from, for example, Berlin. Single axle bogies are a possibility, but I don't think they can manage high speeds. What you might end up with is a Talgo-style tram, that could work. Also, the Rotterdam metro network has used two-car metro trains for a long time, and they work fine. Those are, however, high-floor trains, so they've got much more space. And doors.

[@lzh4950]

@Kichiro Rode the Borbardier Flexity 5000 (which is high-floor & has a more conventional bogie design) on Manchester's MetroLink (light rail) also & I remember it has the similar NVH issue as the Cobras. So I guess the problem might not be due to the Cobra's wheel design

[@JKK_85]

UK Pacer trains were single axel and handled 75mph. They were notoriously rough riding though.

[@petrfedor1851]

Or Jakobi conection with low floor boogies similiar to Škoda 15 T

[@Mr_Stone1]

Now partner up with Talgo, they don't have a tram yet and are using single axle wheels below the links for 'low speed' trains. Time for low floor innovation lol

[@Ghfvhvfg]

I like the idea

[@A_Canadian_In_Poland]

I think many Canadian agecies are wary about high-maintenance issues after the colossal flop that was the Turbo Train (using axles in the articulation joints and pendular technology licensed from Talgo) from 45 years ago. Not to mention two engine fires in its brief 12 year history.

[@simondoes]

basically all new metro trains in germany use plug-style doors that have, imo, a lot of good aspects for what you're looking for, despite being mechanically complex. As they can protrude out of the hull they don't affect the loading gauge of the vehicle or the resulting interior width as it is with sliding doors, pocket or outside; and as you mentioned, they look clean and don't cost window space or interior space.

[@federicomarintuc]

check the floor plans of Skoda 15T. they can accommodate most of what you're asking for. and in the end you can fill with half a meter of concrete each platform and use very low high floor vehicles

[@Myrtone]

Except that the articulation gangways of the 15T are really narrow. As it happens, the ForCity Alfa did not go well.

[@jan-lukas]

It's always a bit confusing to watch these videos as someone used to Stadtbahn from Germany. For most cities a Stadtbahn system is enough and the best, most flexible option, it's easy to put parts underground like a metro because capacity is high enough, but in the night you can only use one half of the train because not that much capacity is needed. Expanding the system to a full metro is also not to difficult, colognes Stadtbahn for example feels not that different from other real metro systems I know while technically being Stadtbahn and even high floor on some and low floor on other lines

[@longiusaescius2537]

Stadtbahn is high floor no?

[@correctionguy7632]

@@longiusaescius2537 yeah hes comparing apples and oranges

[@DasFuechschen]

Do you know the Frankfurt U5 trains? Some of them have only one cab with a coupling and a weather-sealed to another train on the other side. They even built units without any cabs to form trains up to 100m. This allows them to have the high capacity you advocate for while also preserving the operational flexibility smaller units have. Now while those trains are not low-floor, the fact that these trains are part of the Flexity-Family means it could be possible to build these in low-floor versions (maybe not 100% low-floor at the couplings) .

[@RMTransit]

Hilariously I was indeed discussing just those specific trains with someone when I was working on this video!

[@simondoes]

The TW2500 Series in Hannover's Stadtbahn works much the same way; two TW2000 series trains with only one cab and and bellows on the other end connected together.

[@JohnFallot]

Instead of RMHCLMT, I prefer calling these FULL-CHARM Trains: Floor Undercarriages Lowered Luxuriantly Capacity Heightened Articulated Rapid Metro”

[@RMTransit]

Are you looking for a job? I think we may have found our first marketer

[@JohnFallot]

@@RMTransit Unironically yes 😂

[@flare2000x]

Honeslty the CHARM part makes a lot of sense for this vehicle!

[@JohnFallot]

@@flare2000x The Stadler-RMTransit CHARM?

[@JustBen81]

As someone who lives I city with different trams that have 2 doors per intermediate segment and other trams with just one door: 2 doors is definitely better. You don't get much efficiency for the intermediate segment but the bogey segments can disembark much faster if the door is right next to them - since these segments are tight mots standing passengers cluster around the doors when you have just one per intermediate and don't use the full length of the train.

[@nuvaboy]

Honestly though, I think Siemens Avenio trams, specifically with the interior Bremen chose, already solve many of your problems, except for maybe the door type. What they bring to the table: 1 bogie per segment, up to 2 wide double-doors per segment and the traction motors are fitted to the bogies themselves, so no awkward high-floor section. Interior-wise, Bremen went for 1 bay of 4, 1 bay of 2 and a bench per side per bogie, 1 L-shaped group of seats in the rear and longitudinal fold-up seats everywhere else. The interior leaves plenty of space for standing, pushchairs, bicycles, mobility aids, and wheelchairs.

[@satiric_]

Siemens Avenio only has a top speed of 80 kph, or 50 mph. Whereas the Seattle Link light rail goes to 89 kph, or 55 mph. Haven't checked the other networks, but at least Seattle would be sacrificing a little bit of top speed in the grade-separated areas by going with Avenio. Otherwise it looks like a good solution, though

[@dav_8356]

A lot of German cities (Stuttgart, Hannover, Karlsruhe,etc…) have done exactly what you describe hasn‘t been done before. Take a tram put it in a tunnel, and then later turn it into a small scale metro system.

[@RMTransit]

Not exactly I've talked about these cities and their stadtbahn systems in the past and they are distinct

[@pixoontube2912]

Stadtbahn systems remain distinct from American LRT systems, because in Germany, these systems usually serve towns with populations around 300k to 500k, maybe 1M, but that's fine: Medium capacity transit for a city of medium size. Additionally, the tunnels are usually for trunk sections or difficult terrain, and thus, many branches in the outskirts of the cities still retain a tram-like feeling. However, in North America, LRV is not a suitable solution, as it seems that they are trying to build "low-budget metros" in large cities that actually need proper metro systems.

[@dav_8356]

@@RMTransit yes and no. While I agree (like Pixon) that the Stadtbahn systems are very distinct and more suited for smaller scale operation than the places where the US is building it's LRT. Today's Stadtbahn systems however are a vastly modified version of the trams that initially got put in a tunnel. I'd imagine the development path in the US would not be all that different. The issue of scale remains but is to my understanding not necessarily part of this video. If you need to build trams the size of Reece's explanation, you will need to think about a proper Metro/S-Bahn system. The systems in the US are built, yes. But not set in stone. I'm interested to see if and how there will be development to them in 10 or maybe 20 years.

[@szurketaltos2693]

I was gonna say, the Brussels premetro is exactly trams in tunnels for highish passenger capacity.

[@pixoontube2912]

@@szurketaltos2693 Yeah, but it was meant as a temporary solution.

[@placeholdername0000]

I like the Lint 41 solution to low platforms. Having low floor sections between each bogie works quite well. Not problematic due to the large sections. Not light rail but still.

[@RMTransit]

The issue ends up being turning radii as well as accessibility it all really depends on how things are designed and how they are operated

[@offichannelnurnberg5894]

A blind kid fell over the stairs the day before yesterday on such a train. Not LINT but Desiro. So not ideal.

[@augu2464fromdk]

As a person who frequently uses the S-tog, I like your danish inspiration, but I thought of the Ic3 because of there front, then the cab isn’t dead space and if something goes wrong you can just get it away. But it’s was definitely an interesting idea and video😀

[@Clenched.Cheeks]

DOUBLE DECKER TRAMS BABYYYYY WHEEEEEEW!!!

[@henryyu1018]

well, your tram has a small bug: it cannot(at least it will be difficult) go through s-curves. each carriages’ facing is fixed depending on the shape of the rail, so you need more complex connecting points or a floating carriage. (i can’t express in english very well, try to draw the tram going through a tight s-curve looking from above you’ll see why)

[@or2kr]

Motors under longitudinal seating in a low floor segment just doesn't work. The biggest thing that is stopping LRVs from having higher capacity is the smaller turning radii required to be operated on the street. The Stadtbahn in Cologne for example has per vehicle only two joints, both placed closely to the center unpowered bogie, while the motors are on the outside rotating bogies at the end of the train. This already improves capacity a lot, but also means that the train doesn't fit through the smallest streets. It does a good job though at being a metro imo

[@oskarsyren]

@rmtransit I love this attempt to improve the tram :D Keep em coming

[@matthewkirk6905]

i started watching this channel because i like trains and trams and it has been so far the best channel for quality content that i watch on the regular and the fact that you have now proposed a new designed for a tram/high capacity low floor I'm glad i stayed and subscribed :)

[@mxv456]

After spending a night in a sleeper wagon, I tried to come up with a better and more efficient system (my whole compartment was snoring). It ended up looking a bit like a cattle train with lots of little boxes. I suspect that most people wouldn't appreciate it but I would love it :)

[@nace888]

While this design is very very clever, here's my concerns. Having worked in public (or private) transportation (in more ways than one) you have to find that quite a lot of people prefer seating as well... By doing your design, you're only guaranteeing a 1 to 3 ratio of seaters to standees... Unfortunately, adding more doors also adds MANY MORE complex parts that are liable to go wrong. WDW Monorail comes to mind, 12 sets of doors on one side of a 6 car train, the doors act up from time to time. Despite the angle you were going for, I'd suggest that every other car has a door. With your shortened sections on your "FULL CHARM" trainsets (I saw the comment, I like it) it still allows easy access into the cabin AND the doorless cabins can be full wall seating. Just a thought. We (unfortunately) live in a society where you have people that will automatically take seats (even when they don't need them) leaving no seats for the elderly or special assistance passengers. With that being said, I quite like the thought process behind this! I've sketched up my own designs over the years myself, so I like what you're going for!

[@lzh4950]

7:04 Having 2 smaller instead of 1 large door means each door takes less time to finish opening & closing though (as each door leaf needs to travel a shorter distance), allowing for shorter dwell times at stops/stations. If you're worried about higher energy consumption due to more motors needed if you want to open more doors, perhaps every 2 neighbouring doors could be mechanically connected to a single motor (unless you want to allow selective door opening)

[@nace888]

@@lzh4950 it was meant to say every other car has "a set of doors". Half the amount of doors with the same concept.

[@Blaze6108]

Proposal: use Talgo-style wheels, without bogeys and one wheel on each side on each segment interconnection. It's not like you're gonna put anything else in that space anyways. This basically frees up ALL internal space, and while it does reduce the amount of wheels-per-kilogram, trams already have enough small segments to probably compensate for this. Not sure if you could fit them INSIDE the interconnection, but it's worth a shot.

[@ShadowOfAntioch]

This looks EXACTLY like the Bybanen in Bergen! (Which, by the way, you should absolutely cover in a video. A beast of a tram with amazing frequency, connects the airport to the city centre, and has really cute custom jingles for every stop)

[@benkonto9499]

Im from bergen and totally agree

[@mariachrzski18]

I've always wanted to see a new tram design! Thanks for making a dream come true!

[@anteeklund4159]

Single wheelsets (not boogies) severely increase noise and vibrations, severely decreasing the ride quality. I'm much more fond of the idea of putting boogies under the articulations

[@ARod4374]

@@stephenspackman5573 You could design a bogie where the bottom of the crossmembers are dropped to

[@ARod4374]

@@stephenspackman5573 Possibly; I could see things being better these days with modern microcontrollers and electronic suspension systems. The big question with that is how much space you wind up saving with that system over a modified bogie setup, and what the complexity and reliability penalties are for taking that approach (especially when you're trying to maximize interior low-floor space without compromising serviceability).

[@fredblonder7850]

“boogies under the articulations”??? You want a boogie-woogie train?

[@Ghfvhvfg]

Jacobs boagies exist so there is a way

[@its-eric]

I really like this! I’ve always thought that low floor trams could be much more space efficient and this is so satisfying to see visualised. The only thing I might add would be two/three slightly longer segments (like on Citadis trams) distributed evenly to allow space for either wheelchairs or bicycles since these smaller segments from the Flexity Freedoms don’t appear long enough to have space internally on either sides of the doors.

[@HenryLoenwind]

You're missing something about human psychology: No matter how wide the doors are, their capacity is at most 2 people side-by-side unless you add additional dividers. People don't split doors into 3s and 4s by themselves.

[@ilyapetoushkoff8362]

Skoda 15t is probably one of the best low-floor light rail designs currently available in the market, and the amount of low-floor space there is quite enough to even offer longitudinal seating layout if necessary. Other than that, I would be probably looking into the heavy rail domain, sourcing thoughts from either something like Stadler Kiss or probably something like Talgo high-speed train in terms of what kind of car typology is achievable.

[@ilyapetoushkoff8362]

(sorry - meant Stadler Flirt)

[@Rahshu]

That was cool! I've really come to enjoy hearing you talk about rolling stock design. It really is underappreciated, and I'm glad I'm being cured of my prior indifference to it. I can see also why you seem generally to prefer more deliberate selection of mode rather than trying to mix various things together into one package that doesn't do any job well. If you need a metro, build one; if you need a tram, build that. Seattle is, by US standards, building an impressive system. Considering the money being sunk into it, it would probably have been just as cost effective to build a traditional metro to serve the city. Unlike the first built segment, they've gone really gung-ho on building grade separations at great expense and long ass platforms for equally long train consists. The frequencies ain't bad either. I guess the lesson is to regard our infrastructure as an investment in the future so don't mind the costs so much. Building the cheapest option isn't necessarily the best idea, and if you're a rich country, being a little extravagant shouldn't really be a problem either. Put in the effort to not only make the system high quality but attractive, something people can point to and be proud of. Utilitarian designs don't usually inspire such feelings.

[@andrewclarkson3401]

This is exactly what we needed. It shows how future trains on these lines can have higher capacity. Some skeptics will probably need to see it, though, to believe it. I suggest you just go ahead and build some trainsets, sneak them onto the Eglinton Crosstown line, and I'm sure Metrolinx will want to pay for them once they see the benefits! 😁

[@AlvaroALorite]

Why are there sudden cuts in the video? Was it because of copyrighted material?

[@greendude96]

The design reminded me a lot of the ULF trams in Vienna :D but there the wheels are somehow in the articulation bit :D

[@1.125-u6i]

9:00 I'm sorry, but Prague isn't in Eastern Europe. It's Central Europe.

[@redheads604]

although these are nice suggestions, ultimately I think the best solution is to avoid low floor vehicles unless really necessary. Even if parts of the system runs at-grade, using high floor trains is just better for capacity. It doesn't need to be super high floor, just high enough so that bogeys and internal components don't obstruct the interior cabin. With proper planning, the platforms can be high floor without sacrificing accessibility. In the long run, it's properly cheaper than ordering potentially complicated rolling stock.

[@smurftums]

It's going to attract the "Reece's Pieces" nickname... :) Spacing of the wheels would have to be carefully considered as derailment could be a risk with a greater distance between the wheel centrelines. The ride on substandard track could also be an issue. Free rotating bogies (Jacobs or otherwise) allow for bogie movement independent of the car body, giving a smoother ride for passengers. One possible extra capacity hack, any transverse seating should also be flip up seating for use when the vehicles get really crowded.

[@ricktownend9144]

One of the great aspects of your channel is that it can be a forum for good ideas and best practice in the transit world. Now you've done trams, any chance you could tackle tram stops - and bus stops for that matter. Travellers can actually spend as much time at these as they do on the vehicle...

[@eonflare14]

Perth, WA actually has some of these same things on the "metro"/suburban trains, being narrow gauge they dont have a lot of standing room and the plug-style doors

[@jarjarbinks6018]

I figured that in order to accommodate higher capacity in the future Seattle would possibly just have to grade separate rainier valley and SODO with everything else being grade separated but it appears that I was sadly mistaken as even on the east link segment there are grade crossings along the disused track that Sound Transit bought from BNSF. I find some of the decisions they’ve made to be pretty shortsighted given how little savings the capacity compromising aspects of link are compared to its absolute price tag which will be high either way. It would require modification to multiple platforms but I honestly wouldn’t mind the link vehicles being replaced with vehicles possibly using similar dimensions to those found on Septa Regional Rail trains. Build new ramps at the at grade stations in the suburbs and raise the floors of the underground and above ground stations in Seattle. Much easier said than done though

[@unconventionalideas5683]

This is actually something that could really reduce construction costs when building new stations on new metro systems because tall platforms can be expensive, and if you combine low floor with low interior height more comparable to that of say, the Glasgow Subway (which is a little extreme, but illustrates the point), then you could drastically reduce overall construction costs by reducing tunnel size and platform height, if that makes sense, and would do so without sacrificing capacity. Does that make sense? Edit: typo, oh, and the Siemens ULF trams in Vienna had most of these features.

[@stroll-and-roll]

Cologne (a city with slightly over one million inhabitants) also just uses light rail trains for their metro-style system. The still have an S-Bahn system tho.

[@TheMexxodus]

It's an interesting proposition, but it looks too much like a translohr on steel wheels instead of rubber tires. I still like the ULF tram design of Vienna and the trams with bogies under the connections like Prague. But I feel as these solutions aren't industry-wide adopted, they must have some serious drawbacks that hinder technical adoption.

[@JaapFilius]

Nice video. Some tramcompanies in Europe are at the moment in doubt how to handle the lowfloor concept: existing trams are having their issues resulting in more trams in the workshop as planned. Not to mention extra maintenance costs on the infrastructure. So some companies has decided to do a stap backwarts in favour of traditional bogies. One exemple: RNV (Rhein Neckar Verkehr) in Germany has ordered new trams from Škoda to replace the first generation of lowfloor trams, the first of which will be delivered this year or next year. The bidirectional trams will have 3, 4, or 6 units, each 10 metres long. Every segment will rest on two bogies. The 4 and 6 unit-trams can be split in half in case of maintenance or repairs. That way they do not have the need to rebuild the workshop. RNV is expecting much better comfort AND a reduction of 25-30% in costs for tram- and trackmaintenance.... The consession RNV has choses for is a tram with "only" 75% lowfloor because the seats above the bogies are placed on so called podests. In my view they have made a good choise: most people have not a single problem to climbe a small stap and trams on fixed trucks are not running very well in curves.

[@gamingbandit42]

The approach by Manchester is good where trams AND PLATFORMS are high floor. And yes the system is accessible because the platform height is still the same as the height of the door and tram. This means that the bogeys and electrical equipment can be shoved under the seats without requiring steps above

[@gregderise9969]

I like it. I like it! So much salt put into it and so many interesting knowledgeable comments by people who obviously have many different experiences and interesting knowledge to add. I like this kind of content and I hope you do more of it, perhaps investigating some of the systems mentioned by your commenters.

[@SiqueScarface]

Running multiple-unit trams as subway trains is for instance done by Verkehrsgesellschaft Frankfurt am Main, Germany. At first, Metro and Tram in Frankfurt am Main were not separated, and the Metro used the Tram lines for instance to access the depot. Only with time, tram and metro got more and more separated, but because of the hybrid state, special rail cars, the Class Ptb, were used in some parts of the network. Ptb can serve both level tram-like stations and high floor stations.

[@JacobOhlssonBudinger]

i always thought that with some more considerations for strengthening, it’d be cool if we could use the Vienna Tram strange-bogie things in-between slightly longer cars of say 14m, packing on 3 doors per car side. the bogies at the very front and back would be normal bogies with these cars sacrificing a door. idk if it’s feasible given this weight but i think if it is, you’d pretty much have a normal metro train, at least from the inside, where you have the freedom to design it as any other metro train.

[@muthisamwernergruber]

The ULF "Ultra low floor" wheel assemblies are extremely expensive to maintain. There's a reason newer trams aren't build that way

[@JacobOhlssonBudinger]

@@muthisamwernergruber i’m aware, but this whole video is about an expensive solution to an expensive mistake in transit planning. price isn’t really the point

[@ft4709]

A lot of people in the comments mentioned Frankfurt‘s U5 but I‘m kind of surprised nobody’s talking about the Typ T trains of Vienna. I‘m pretty sure those are basically the very first low-floor trains ever used on a proper metro line and they seem to perform quite well. Sure, the number, or at least width, of doors could be improved, just like there really should be an open gangway at the rear end. But I much prefer their layout to the more common flexity swift versions in, say, Cologne or Croydon.

[@gobyrail]

Fixed wheels instead of bogies will create a lot of noise and a lot of wear and tear on the wheels and the rails. They will also result in a very uncomfortable ride for the passengers unless you do something clever with the suspension, which will take up a lot of the space you've saved. Bigger doors mean you lose a lot of structural rigidity, which means you need to compensate by adding strengthening beams somewhere else in the vehicle, and that space can't have windows or doors. If you want to run a metro service on lines with low level platforms, the only way is to run partial low floor vehicles instead of 100% low floor. The doors can be at platform level but the floor can slope upwards inside the vehicle to create more space for the mechanical engineers to do their magic. All that said, I agree with you that we need longer vehicles rather than coupling two or more short vehicles together.

[@erdemkurucu9092]

High floor trams are king. B2 class tram gang.

[@GustavSvard]

Given that the aim is specifically for a high capacity LRV to be used in metro style services, you did good. Real good. This is exactly that. Not the right fit for most systems or most lines, no, but that wasn't the aim. And stepping away from a one-type-for-all for LRVs is the right thing to do. It is already done, of course, but this fills a niche that currently is NOT filled. 5/7 best ever.

[@uncinarynin]

I think that adding more wheels also means adding more weight, cost, complexity and takes up more inside space. Also getting rid of bogies means that the track must be a lot smoother because single wheels aren't as forgiving on bumpy tracks. As I understand the ULFs have their issues, which is why the Flexity chosen for the next series has wheels under the first, third and fifth segment. Your idea also reminds me of the Cobra in Zürich, which however doesn't seem to be that much of an advantage: It's not been ordered by any other system and they too went for a Flexity similar to the one in Vienna where sections with doors and wheels are alternating. (As a side note I don't like the plastic seats of Vienna or the wood seats of Zürich ... leather seats as on the newer Cityrunners in Linz are nice.) Now sliding doors on the outside are rare on trams. I assume they limit the width of the body which means less inside space for a given total external width. The plugging-sliding doors only take up extra width when open, allowing for more inside space which adds to comfort and capacity. I know that London Tube uses outside sliding doors, class 485 on S-Bahn Berlin would be another example, but otherwise they don't seem to be all that widespread ...

[@RMTransit]

To be fair part of the issue with track quality in Vienna probably has to do with the fact that you're operating with embedded tracks which is something we don't have to worry about on these routes for the most part

[@RTSRafnex2]

​@@RMTransit This should not make any difference, as streetcar tracks are usually laid the same as ballastless tracks. The only difference is that streetcar tracks are filled afterwards.

[@WizenedVariations1]

Most of the modern low floor designs with segmented cars are designed for very tight radius curves (the wider the turning radius the longer cars can be). This is combined with street running and the expense of high floor stations (need to reduce cross track pedestrian traffic) created the entire low floor concept. IMO, conventional train bogey set ups can be made smaller and wheel wear reduced through good design- work on torsion bar systems (and more attention paid to track maintenance). Flat floor trains can be made with more equipment on the roof of cars, motive systems can be linear induction or linear induction hybrids and used in conjunction with dual sided station platforms.

[@Michael-he7xn]

RHCLFMT Innovation at its finest! Ya never know where grand ideas come from. 😁👍

[@Michael-he7xn]

By the way. There’s a great screen shot of you peeking through the ‘C’ the last time you mentioned RHCLFMT. (Is the concept patentable?)

[@RMTransit]

I thought so myself I had to give it a catchy name

[@bruteforce_programmer4942]

Is it possible to use highfloor tram and then sink the rail near stations, to make it accessible from low platforms ?

[@georgobergfell]

I was thinking about that too. Maybe low floor stations and platforms should be built in a way so this option is possible

[@lzh4950]

6:36 Japan has trains & buses with windows at the door pocket areas though e.g. Tokyo Metro's 15000 series, Hino Blue Ribbon, Isuzu Erga

[@chrissexton4129]

Seattle has low floor trams partly because a portion of the Light Rail system travels on the street with traffic. Because of the stations on street level, turnstiles are not used on the entire system to prevent people from walking on the tracks to get around the turnstiles on the street level stations. Furthermore, New York Post reported recently that upwards of 70% of Seattle Link passengers don't pay the fare because there is no fare enforcement. Poor planning from the start.

[@rossbleakney3575]

There is also the transit tunnel. Originally built for buses, it was shared with buses and trains for several years. The buses that used the tunnels had many stops outside the tunnel, which means that even if they used high platform buses, the city would have had to commit to lots of higher curbs throughout the city, making the idea impractical. The time to change things is when they decided to kick the buses out. At that point, they could have raised all of the existing station platforms and switched rolling stock. I believe there were 17 stations then, with about 40,000 riders a day, so while it would have been very disruptive, it seems quite possible. It is up to 25 stations now, and that will quickly grow over the next several years. None of this has anything to do with the lack of turnstiles. The original bus tunnel was designed so that turnstiles could have easily been added. They simply decided against it, preferring to follow the German model.

[@mobilinsan]

Fun fact: Multiple units of Marmaray (İstanbul), Başkentray (Ankara) and İZBAN (İzmir) suburban lines have plug doors on them which haven't occur a problem in terms of operation.

[@JoseRodriguez-tb1js]

Actually, I like your design. It has very good ideas in it and solves many endemic problems of maintenance. A good modular design will permit replacing the entire engines at once making maintenance more efficient and ultimately low cost. Eventually, some manufacture is going to reach out to you.

[@Jytami]

having a flexible fleet of light rail-based train sets with interconnection between segments is actually possible. Frankfurt recently ordered new "middle segment" sets consisting of two wagons which don´t have a full driver cabin but a "half" cabin to rearrange train sets. Which means it is open on both ends and can be coupled to train sets which do have a full cabin. Since Frankfurt´s U-Bahn operates with two-wagon trains either consisting of two full driver cabin at each end or (that´s the part you´ve been waiting for) one full driver cabin and an opened end to couple with another. You see where this "two open end" wagons fit in, amr?

[@oscardaone]

I actually like the door idea. 🤔 Extra sliding doors.

[@haweater1555]

9:00. Toronto's ALRV had wheel bogies in the articulation joint.

[@youtube79z]

would having 70% low-floor instead of 100% resolve these bogie problems?

[@cityjetproductions]

It depends on the specific vehicle. If there's just one small step up at each end of the vehicle it would be well worth having a partially low floor vehicle for better running characteristics. If there are multiple steps up to the high floor areas and they are spread out throughout the vehicle a fully low floor design might be a better choice.

[@quoniam426]

The old way,

[@Zenit_Bourg]

Yeah i favour sacrificing the 100% status instead of design mental gymnastics

[@jonathanj8303]

Mix it with articulation, maybe with the train split into subunits, like the Norwegian class 74 and 75 flirts (but without 200km/h capacity), and I think it's a better compromise. And you can make the platforms match the trains, because the high/low floor bits are always in predictable places.

[@RMTransit]

It would solve them to some extent but the stairs hurt circulation and accessibility which I don't like

[@TheCreepy31]

Basically an ULF from Vienna, I don't think with this design the structure would be capable for high speed ( ~100 km/h ) but for tram operation why not. One design I like for high capacity is the Skoda 15t, clever design and has a lot of space. Something with a similar design but way more larger would be better imo.

[@matejlieskovsky9625]

Have you *seen* the specs for the maximal Škoda 15T? 100% low floor, up to 72 meters and 540 passengers, can be double-ended if needed.

[@matejlieskovsky9625]

I don't know why, but this video is irritating me. Bogies are needed for a good ride and we know how to make them fit into low floor trams (see the 15T). I believe there was also some research about wide doors *not* being as good as having more doors (assuming everyone can fit through a door). I don't know who maintains doors in the Americas, but you shouldn't need sliding doors unless you're squishing in people like the japanese do. And good luck having completely independent wheels that turn into the corners as your animation suggests! Gah!

[@1.125-u6i]

@@matejlieskovsky9625 Not mentioning Prague being considered a part of Eastern Europe instead of calling it properly *Central* Europe. It's even more to the west than Vienna, which isn't considered eastern be anyone.

[@ixofxiii]

i like this one. Brings me back to when i worked on a new Philadelphia streetcar for fun. BTW, Id call your design "Reese's Pieces" with all those sections!

[@KU8676]

Actually this train is quite high capacity, but people just hate standing, whether it's a short journey or not. Therefore, I suggest to merge two "cars" into one and keeping only one door for each. Except from the extra seats, also, this can help make larger doors, and a few seats with space underneath. The space underneath can be quite useful, like putting luggages under the seats, which would also increase the spaces for standing. I think more seats is for both higher quality travel and more passengers. Imagine the tram as a bus, people can easily get a seat and this is one of the main reason people taking buses. More seats can provide a better journey, so actually if the capacity lowered by a bit, they can just buy one or two more tram!

[@angusbergman2355]

Melbourne announcing their brand new tram models today. Some impeccable timing this video seems to be ;)

[@seatsea0]

The ULF is a very complex design which only really makes sense for vienna, a very large network with platforms at basically curb height, and a very small loading guage making every square meter of interior space count. But it comes with it's shortcomings like a fairly low top speed, complicated electronics to steer the wheels, which can fail somewhat dramatically at times and despite this they are still quite cramped feeling trams. The Skodas proper bogies, while having some technical shortcomings of their own are probably the better option and solves the issue that trams like the Citadis have, their fixed/limited motion axles end up being very noisy and riding quite rough.

[@lovedfriend2020]

I love this type of video!

[@Lucius_Chiaraviglio]

I have a different idea for a high-capacity low-floor train: Look back to the Boston Elevated Railway's Center Entrance Cars of the early 20th Century. They weren't 100% low floor, because they had ends riding on normal bogies, but they did have large low floor center sections with 1 BIG sliding door on each side, and lots of standing room; they gained the nickname "crowd-eaters". They were mechanically very simple (no articulation junctions, weird suspension, or strange lateral sequences of axles to make otherwise isolated wheels track properly). This would make maintenance easy and infrequently needed assuming good quality of parts and assembly, as well as greatly reducing initial capital investment. What killed them was the lack of a proof of payment fare system, so that you had to have a conductor in each car as well as a driver at the front, but having a proof of payment fare collection system would get rid of that problem. If you additionally made the control stands fold up into the sides/ends of the car when not in use (and have each control cab have a big interior sliding door that you leave open when not in use), they wouldn't even take up much horizontal space. (Naturally, you would need to have the control stand fold into a locked cabinet when not in use, but I understand that this has also alredy been done on both streetcars and metro cars.) Of course, you would want to modernize the Center Entrance car design to have pantographs (instead of trolley poles) and AC propulsion, as well as add air conditioning (although consider running fans to draw in outside air instead of running the air conditioning when the outside temperature is right for it, to save energy). In systems that have less sharp maximum curvature than Boston, you could also make them longer for more capacity (after a certain point, you would need to go to 2 or more doors on each side); but even in Boston's system, a 6 car train of these would have almost the same capacity and be about the same length as a 6 car Blue Line train (metro that uses short cars due to being originally made by conversion of the East Boston Tunnel from a tunneled streetcar line into a rapid transit line, which had the unfortunate effect of breaking the one seat rid people were getting before). No fantasy design needed -- everything has been done on some successful transit vehicle or other. It just needs to be combined into one package.

[@xymaryai8283]

that vehicle would have unmatched curved platform performance too, dynamic loading gauge because of end and center throw on the middle segments is basically eliminated but yeah, the drivetrain was very quickly handwaved, thats a very complex system with a lot of active components. i'd sacrifice a little bit and have undulating floors to allow for axles of some description, even if they aren't axles at all, more like steering racks

[@UserUCKANAOD8SlYguEhbCkUdlMQ]

Have you taken a look at Sheffield Supertram for example though. A good mix of high and low floor. It's a low floor tram in terms of it enables the lower 'kerbside' boarding and whatever but some areas are higher floor such as the centre part and both cab ends. Higher cab of course make it easier for drivers to see what is going on on the roads and the higher centre car could be used for more mechanical things. Or depending on how many bogies need to be motorised, you could keep the centre car low floor with unpowered bogies.

[@philiplokodi6754]

The U6 Service in Vienna uses such Trains you mentioned in this Case the Trains used in Vienna are 3 Car Low Floor trains with all Bogies are Driven

[@JohnDoe12515]

Love it! I used to operate TTC streetcars. Legacy CLRVs were the best

[@resender329]

One solution to get long trams could be a modular design where a control cab could easely be switched for a bay window or connector piece.

[@carpanatomytony]

i love your design!!

[@glx1987]

60 Meter low Floor Trams are in some Citys planned oder in Use. Often you can split them up in the middle. And if you build a Frankfurt U5-MW, only as low floor, you can make your Tram as long as you like.

[@andreferreira6357]

Go check Porto, Portugal LRT Tram mix system. let us know what do you think about it.

[@RMTransit]

Stay tuned

[@SterbenCyrodill]

This is the comment I wanted to make. Honestly, as a frequent rider of the Metro do Porto, I think it leaves a lot to be desired, and I really want to know what would Reece make of it lol.

[@WilliamChan]

Suboptimal Optimization has a nice ring to it :)

[@RMTransit]

I agree :D

[@neolithictransitrevolution427]

I'll be sad when you eventually get hired on as a consultant full time and stop making videos, but not disappointed.

[@RMTransit]

Making videos is a lot of fun I don't know!

[@angelgames9351]

Something that could be added to make more short trains instead of a large one is to put a British sprinter like gangway in the back of each tram, allowing you to double the capacity of a single tram, and perhaps adding more standing space compared to a regular tram. You could even do middle sections of a tram with gangways in both sides, that would raise some operational challenges though, since there will be some units without any cabs.

[@malarconxx7341]

pivoting wheels make complex motor instalation. narrows the corridor or you have to put the motors between the wheels conected with a shaft.

[@KenyonKarl]

Port Authority Transit in Pittsburgh uses an interesting high-floor design that features an extra door for low-floor loading. Of course the routes that use these vehicles evolved from PCC car operation so that even high platform stations included a low-platform section (now unused) where PCC cars could handle entering/exiting patrons. Another point is that low-platform only stations are NOT handicap accessible. Of course the old PCC cars weren't ADA compliant either! One complaint I have against super long tram cars is that it is impossible to run short trains during late night and weekend trips when patronage is small. Thus running long trains at such times requires unnecessary energy consumption. What about having enough short units for an effective low patronage service, with those short units combined into a longer train for peak hour service? Another thought is with a mix of tram sizes, long trams might be electrically two trams so that the electrical wiring is close to identical between the short and long trams. This measure of 'redundancy' means that the electrical failure of half of a long tram means that the other half can 'self-rescue' the train (at sharply reduced performance)) so that it can reach a siding until the end of peak frequency service, when there is more time to run the train to the shops. The great virtue of Frank Sprague's invention of multiple unit controls in 1898 was the ability to dramatically change the length of the train to suit the volume of anticipated travelers with no sacrifice of either performance or economy of operation (per car basis). Super-long articulated trams sacrifice that highly variable train length economy!

[@stickynorth]

Great video. May I suggest a spin off version? Design an ideal metro? Personally I see it as a cross between the Deep Tube of London with Vancouver's Skytrain.. Fully automated trains using LIM technology that arrive every 90 seconds but svelte enough to used in the tightest of tunnels... I.e. a Boring Company 12' standard tunnel which is a full 6" fatter than the current OG Deep Tube tunnels in London... If you contracted out the tunnel boring operations to them I am sure you could standardize and simplify a lot of things that make tunnelling so expensive savings costs while using automated rolling stock that again don't need or aren't nearly as vulnerable to work stoppages/strikes as traditional train systems are...

[@randomscb-40charger78]

I'd be interested to see you cover gas turbines, their history and whether or not they should be brought back.

[@RMTransit]

I don't think they should be brought back but I definitely would like to make a video

[@TheWoblinGoblin]

A gas turbine tram just sounds awesome

[@williamhuang8309]

Articulated Bogies like you see on Stadler FLIRT! And yeah, we need the sliding doors. I'm not sure why that design hasn't been used on trams, maybe they look less nice? Also have you considered adding gangways to the cabs like you see on Electrostars? Edit: Also try DLR-style cabs. Controls can be locked away in like a cabinet when the cab is not in use and maybe also have a glass sliding door separating the cab from the passenger space that can be opened when the cab is not in use so passengers can access the extra space in the cab (that's now got its controls locked off and stored away). Add this with the gangways and you'll have: - Better accessibility (can move between carriages) - Higher capacity (extra space) - Cabs on both ends unlike E G L I N G T O N C R O S S T O W N So yeah, combine these features and you'll have a high capacity beast of an LRT vehicle.

[@mtgibbs]

A few thoughts here... First, wider doors aren't necessarily better. In Chicago, we used to have cars with two smaller doors next to each other. That encouraged people to use both doors. The newer cars with one wider door means that only one person enters or leaves the train at the same time, instead of two. Second, the fairly recent 5000 series cars dispensed with the transverse seating in the middle of the car and it's caused a lot of complaints. Many people hate the arrangement, both because it's tight, with several people sitting in a row versus two next to each other in a row so each can overhang, and people say that they don't like staring at other people's mid-sections. The new 7000 series has gone back to a modified transverse seating arrangement. Next, wheels that aren't connected to a fixed axle are problematic as they don't steer very well around curves. Boston, for example, had a lot of problems with this. It can work, but it's temperamental and it's really a lot better to have wheels connected by fixed axles. It may be possible, with modern electronics and a motor on each wheel to compensate for this, but if the system breaks then the train may not be able to be towed out of the way very easily (and it will break at some point). Also, where the wheels/axles/truck centers are located on the car directly affects end and middle overhang in curves and the curve radius that can be negotiated. It's better to have longer cars with fewer axles, if possible, when curves are not as tight. Lastly, the weight on each wheel isn't really that big of a deal. The rail and track can be adjusted to accommodate the axle loads. Even heavier trains on transit still have relatively light axle loads as far as railroads go.

[@niku_4543]

Check about Siemens ULF from Viena. Is the tram that you refer. A modular tram that have short or longer variants.

[@azan-183]

I love these more creative videos!

[@2712animefreak]

Rather than having bogeys on the small sections with large sections suspended with doors, you can also have both the bogeys and the doors on the larger section with small section containing only a few seats (or standing room) for passengers travelling longer distance. You can see this on TMK2200 trams by Končar operating in Zagreb.