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TTC: Streetcar Network

yrt+viva=1system

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Noticing that there were some discussions in the other threads about future streetcar orders. I ventured onto Finland's Skoda-Transtech site to take a look at the marketing material for the ArcticTram after seeing videos.

http://www.transtech.fi/railway/low-floor_tram

What really piqued my interests is whether Skoda-Transtech would be interested in participating in bidding for the future TTC order(s) now that Alstom-Siemens is establishing a base here. The ArticTram seems well suited for our network albeit with some modifications. And they incorporated a traditional free-turning bogie/truck unlike all the rigid trucks that modern low-floor trams use.

ARTIC™ is excellently suited for tram track networks with several small-radius horizontal and vertical curves. To comply with current standards, the entire tram is equipped with a low floor. Thanks to its ingenious structure, the tram combines a full-length low floor with a traditional freely turning bogie under the car, similar to articulated trams.

The flexibility of the three stage suspension system and the articulation solution between car sections adapt to the shape of the tram track and maintain even wheel loads and good passenger comfort regardless of the condition of the tram track. The bogie structure efficiently dampens sharp shocks from the tram track, particularly in the winter. The tram runs smoothly and silently even in sharp curves and over switches, which have posed problems for traditional low-floor trams. This means that wear load on the track and wheels are minimal.

ARTIC™ takes the demanding climate conditions of the North into consideration. The carefully designed platform structure prevents the packing of snow and ice. The accumulation of moisture and condensation water into car structures has been eliminated with meticulous heat insulation and water barriers and moisture dissipation.


Technical Data:
http://www.transtech.fi/railway/low-floor_tram/technical_data

Wikipedia:
https://en.wikipedia.org/wiki/Artic_(tram)

Just some fun reading material for a Sunday evening.
 

DSC

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In the Report to TTC Board on the King Street Project they recommend adding a curve at York:

Streetcar track network enhancements: improving the intersection of York Street and King Street by adding an additional east-to-north movement that allows for more routing options for diversions or adjustments. Layby tracks within the pilot area may also provide an opportunity to provide greater service resiliency with standby vehicles.

It would also add flexibility if they built/rebuilt the tracks on Adelaide, at least from York to Victoria
 
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steveintoronto

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Noticing that there were some discussions in the other threads about future streetcar orders. I ventured onto Finland's Skoda-Transtech site to take a look at the marketing material for the ArcticTram after seeing videos.

http://www.transtech.fi/railway/low-floor_tram

What really piqued my interests is whether Skoda-Transtech would be interested in participating in bidding for the future TTC order(s) now that Alstom-Siemens is establishing a base here. The ArticTram seems well suited for our network albeit with some modifications. And they incorporated a traditional free-turning bogie/truck unlike all the rigid trucks that modern low-floor trams use.

Technical Data:
http://www.transtech.fi/railway/low-floor_tram/technical_data

Wikipedia:
https://en.wikipedia.org/wiki/Artic_(tram)

Just some fun reading material for a Sunday evening.
Whoa! Incredible 'heads-up'. Before even accessing the links, I see the motors on the *outside* of the bogie, which is a brilliant rearrangement of conventional thinking. As well as drive and height advantages, it would also shift the centre of gravity to a much wider stance...akin to standing on the bottom of a ladder with a foot each side to spread the weight and stabilize the weight above.

I'm off to do some reading!

Addendum: Took some time to find more detailed info on the bogies and the "steerable axles" (which is what I thought they meant, but it might be terminology used mostly in the West), and there's a number of really sensible engineering features to these vehicles. Excellent multi-page pdf:
https://www.hel.fi/static/hkl/artic.pdf

Btw: I first thought how 'Dune' (the movie) the vehicles looked with their upright windshields, but it's in fact for excellent utilitarian reasons it's done, all explained in the pdf above.

One word for this in light of the fiasco now ongoing in Toronto: "Envy".
 
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Northern Light

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In the Report to TTC Board on the King Street Project they recommend adding a curve at York:

Streetcar track network enhancements: improving the intersection of York Street and King Street by adding an additional east-to-north movement that allows for more routing options for diversions or adjustments. Layby tracks within the pilot area may also provide an opportunity to provide greater service resiliency with standby vehicles.

It would also add flexibility if the built/rebuilt the tracks on Adelaide, at least from York to Victoria
I quite like the idea of layby tracks; but I think they need to be oriented, of the correct length for, and have the proper connections to support them as passing tracks as well.

That means, as opposed to be off-street, or on a side street, they need to be on King, connected to/from King, and allow for easy-flow passing.

This is important so that the empty car in the pair/trio be allowed to jump ahead and serve the overcrowded stops.

Doing this at even 2 points on the line per direction would be immensely helpful to service.

Its an idea I've pushed before. Glad to see it gaining traction.

Now, about the idea of having mid-route 'hold signals' to space out pairs/trios that form............
 

steveintoronto

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Now, about the idea of having mid-route 'hold signals' to space out pairs/trios that form............
Best way to do this is to stop it from being necessary in the first place: ATO. And with ATO, those 'lay-by''passing' tracks could also be timed stopping tracks, looped closer to the curb, to allow 'express' (only major stops) cars to go through unfettered.

ATO (Automatic train control) allows many higher functions to happen.
Autonomous trams demonstrated in public | Rail Engineer

https://www.railengineer.co.uk › Light Rail

Dec 10, 2018 - Home Light Rail Autonomous trams demonstrated in public .... This solution uses an ATO over ETCS L2 solution from Ansaldo STS, combined ...
[PDF]cbtc for tram - SYSTRA.com

https://www.systra.com/IMG/pdf/systra-cbtc_oct2015-tram.pdf

for enforcing safe tram separation from other trams, road vehicles and pedestrians ... by efficient cabsignal HMI (“in cabin signal”) and/or ATO assistance. When it ...
Autonomous transportation - Alstom

https://www.alstom.com/autonomous-transportation-smart-and-safe-operations

The ATO controls the train speed to optimise both energy saving and driving ... experiment related to the autonomous stabling of trams at the Paris tramway line ...
 

smallspy

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Whoa! Incredible 'heads-up'. Before even accessing the links, I see the motors on the *outside* of the bogie, which is a brilliant rearrangement of conventional thinking. As well as drive and height advantages, it would also shift the centre of gravity to a much wider stance...akin to standing on the bottom of a ladder with a foot each side to spread the weight and stabilize the weight above.
Mounting the motors on the outside of the truck sideframes has been done for many years, as there are virtually no other places to mount them and maintain a fully low-floor car. In fact, if you read up more on the Artic trams you'll find out that they're equipped with an off-the-shelf Voith drive package.

Addendum: Took some time to find more detailed info on the bogies and the "steerable axles" (which is what I thought they meant, but it might be terminology used mostly in the West), and there's a number of really sensible engineering features to these vehicles. Excellent multi-page pdf:
https://www.hel.fi/static/hkl/artic.pdf
The Artic does not use steerable axles. They use traditional, rotating bogies at all four points, which up to that point was highly unusual with a tram with a 100% low floor.

It should also be noted that all of the Artic trams built up to now have been for metre gauge track. There has been an order for trams for a standard gauge system, but it is also for a more "traditionally" designed low-floor tram, and not this version of the Artic - even though it will be branded as such.

Dan
 
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steveintoronto

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The Artic does not use steerable axles.
It depends on your definition of "steerable". There's both passive and active. I'd use the term "steerable bogie" or "wheels" save that this model of bogie has continuous axles. The forward lead bogies (one each end) at least have a sense mechanism for the radius of turn to adjust operating parameters. I'll try and dig more out later on that.

There's an excellent engineering discussion on low floor tram bogies here:
http://www.transoneleng.org/2015/20151c.pdf

And one of Voith's pages here:
https://stories.voith.com/most-liveable-electrified-helsinki-51415/en
and:
http://voith.com/corp-en/drives-transmissions/gear-units/gear-units-special-purpose-vehicles.html
http://voith.com/corp-en/news-room/press-releases_75729.html
 
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smallspy

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It depends on your definition of "steerable".
No, it doesn't.

A steerable axle is one which it is able to rotate and continue to be perpendicular to the rails.

A truck can steer, but unless it also has steerable axles, the axles will never be truly perpendicular to the rails in curves.

When it comes to bogies, the term "steerable" is very clearly defined.

Dan
 

steveintoronto

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When it comes to bogies, the term "steerable" is very clearly defined.
OK, then define this:
The tram runs even the sharpest of curves and the steepest hills and valleys smoothly. It is also the first tram in the world to effortlessly master any combination of all three. The multidirectional articulations and freely-turning bogies ensure good passenger comfort and long vehicle structure service life in all conditions.
Helsinki's New Tram - Transtech

Note:
The bogie of the tram combines proven high-quality solutions with the latest low-floor technology. The bogie structure is based on the articulated bogie solution, which has been successfully used in rail vehicles for decades. The bogies consist of, among others, traditional wheelsets with continuous axles, coil springs in secondary suspension and large wheels. These highly reliable solutions combined with the low-floor structure, short wheelbase, very flexible rubber elements in wheels, and compact traction chain result in a tram that runs reliably and cost-efficiently in the most demanding conditions for years on end. The advantages of the bogie solution include excellent running behaviour, even in the most challenging track conditions, its light weight, minimal wear and tear on wheels and rail, and low life cycle costs.
https://www.hel.fi/static/hkl/artic.pdf

Emphasis on "very flexible rubber elements in wheels". That's for radius compliance as much as vertical undulation absorption, curving performance and dynamic stability.

There's lots of detail here:
https://www.researchgate.net/figure/A-light-tramway-equipped-with-bogies-with-independent-wheels_fig1_267830130

And to those wondering what an "articulated bogie" is:
Articulated bogie
An articulated bogie is any one of a number of bogie designs that allow railway equipment to safely turn sharp corners, while reducing or eliminating the "screeching" normally associated with metal wheels rounding a bend in the rails. There are a number of such designs, and the term is also applied to train sets that incorporate articulation in the vehicle, as opposed to the bogies themselves.

If one considers a single bogie "up close", it resembles a small rail car with axles at either end. The same effect that causes the bogies to rub against the rails at longer radius causes each of the pairs of wheels to rub on the rails and cause the screeching. Articulated bogies add a second pivot point between the two axles to allow them to rotate to the correct angle even in these cases.
https://en.wikipedia.org/wiki/Bogie#Articulated_bogie

[...]
Suitable for demanding conditions Transtech’s ARTIC® is excellently suited for tram track networks with several small-radius horizontal and vertical curves. To comply with current standards, the entire tram is equipped with a low floor. Thanks to its ingenious structure, ARTIC® combines a full-length low floor with a traditional freely turning bogie under the car, similar to articulated trams.[...]
http://www.transtech.fi/download/103/low-floor_tram/pdf
 
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smallspy

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OK, then define this:

Helsinki's New Tram - Transtech

Note:

https://www.hel.fi/static/hkl/artic.pdf

Emphasis on "very flexible rubber elements in wheels". That's for radius compliance as much as vertical undulation absorption, curving performance and dynamic stability.

There's lots of detail here:
https://www.researchgate.net/figure/A-light-tramway-equipped-with-bogies-with-independent-wheels_fig1_267830130

And to those wondering what an "articulated bogie" is:

https://en.wikipedia.org/wiki/Bogie#Articulated_bogie


http://www.transtech.fi/download/103/low-floor_tram/pdf
There's nothing to define there. They don't use the term steerable to describe the trucks or wheels.

Once again - "steerable" means something very specific. What they are describing are rotating trucks, which, once again, was a very unusual thing for a fully low-floor streetcar to have until very recently.

Since you're fond of Wikipedia entries, please allow me to point you to this one: https://en.wikipedia.org/wiki/Radial_steering_truck

Dan
 
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DSC

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There's nothing to define there. They don't use the term steerable to describe the trucks or wheels.

Once again - "steerable" means something very specific. What they are describing are rotating trucks, which, once again, was a very unusual thing for a fully low-floor streetcar to have until very recently.

Since you're fond of Wikipedia entries, please allow me to point you to this one: https://en.wikipedia.org/wiki/Radial_steering_truck

Dan
Dan: I am afraid you are wasting your time; some people are too set in their ways to change or adapt their ideas to reality or facts. :->
 

steveintoronto

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A steerable axle is one which it is able to rotate and continue to be perpendicular to the rails.
That's *EXACTLY* what an articulated bogie does. Call it Fred for all I care. It's steerable. *Even if it has no continuous axles*!

And a reminder as to where your nose got out of joint:
steveintoronto said:

Addendum: Took some time to find more detailed info on the bogies and the "steerable axles" (which is what I thought they meant, but it might be terminology used mostly in the West), and there's a number of really sensible engineering features to these vehicles.
I posted a link to this, obviously you didn't access it, or if you did, you couldn't read it. The authors of this and many articles on the subject are not American, and thus use a different terminology to achieve *exactly as you yourself describe it*:
The articulated bogie


The articulated bogie
Source publication
A light tramway equipped with bogies with independent wheels
The articulated bogie
The bogie in different deformed configurations
The closed morphology of the bogie: top view
A single wheel on a rail - auxiliary variable w and θ
Flange wheel/rail intermittent contact
https://www.researchgate.net/figure/A-half-tramway-model-Simpack_fig7_267830130?_sg=oISbGq6BtFVUQiIuLqawSUKYFfggWgnnIvCb6qJpqmzSm4IeJypeePZIcIrTktc9xTJl3Km5dDpoJ740fzuxoCA5YzwFvbx2n6sYlJpkfw

TRAMWAY/TRACK INTERACTION: DYNAMIC ANALYSIS AND PERFORMANCE EVALUATION OF AN ARTICULATED BOGIE WITH INDEPENDENT WHEELS
Article
Full-text available

View
Contexts
Context 1
[...] The use of independent wheels certainly represents one of the most ”revolu- tionary” innovation of the last decades. Indeed, it aims at replacing the traditional wheelset which exists for more than one century and is at the root of the bogie guidance thanks to its well-established self-steering capability. [...]
https://www.researchgate.net/figure/The-articulated-bogie_fig2_267830130

Even just the quoted text of the opening page sample mentions "steer" ten times.

Perhaps if you weren't so beholden to calling others out, you could see a world beyond your own, but alas...There's a lot more "steerable" in the world than just the EMD patented term. And in the case of the Transtech bogie, they use *continuous axles*. The bogie frame itself, as they aptly and repeatedly state, 'articulates like the carriages themselves'. As to how that 'articulation' 'pivoting' or 'steering' happens is unique in many cases. It's unique in the case of Transtech bogie, and an exact engineering discussion is proving difficult to find. Somehow they've achieved articulation in all planes with continuous ('solid' by your terminology) axles.

Just because it doesn't fit *YOUR* understanding doesn't mean it doesn't meet established and proven engineering terms and standards elsewhere.
 
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Jonny5

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In the Report to TTC Board on the King Street Project they recommend adding a curve at York:

Streetcar track network enhancements: improving the intersection of York Street and King Street by adding an additional east-to-north movement that allows for more routing options for diversions or adjustments. Layby tracks within the pilot area may also provide an opportunity to provide greater service resiliency with standby vehicles.

It would also add flexibility if the built/rebuilt the tracks on Adelaide, at least from York to Victoria
Diversions are often more trouble than they are worth when the average rider is so confounded by them that their brains shutdown sending their lives into a total meltdown, halting the service while they demand the driver stop and provide a detailed explanation to them of what is happening, and then seven people behind them also demand the exact same explanation be individually provided to them, after which they all spend four or five minutes in the doorway pondering whether or not to get off.

Even the regular daily westbound 503 trips are a nightmare for some people, and these aren't newbie riders, but people who have made thousands of trips on the TTC. You can see them at the back when the bus or streetcar turns at Church Street frantically pulling the cord 50 times in a row, thinking that will make the vehicle stop for some reason. Then when it finally gets to the next stop they will walk to the front to exit, then turn around and walk back past the door they could have exited anyway.
 
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DSC

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Diversions are often more trouble than they are worth when the average rider is confounded by them their brains shutdown sending their lives into a total meltdown, halting the service while they demand the driver stop and provide a detailed explanation to them of what is happening, and then seven people behind them also demand the exact same explanation be individually provided to them, after which they all spend four or five minutes in the doorway pondering whether or not to get off.

Even the regular daily westbound 503 trips are a nightmare for some people, and these aren't newbie riders, but people who have made thousands of trips on the TTC. You can see them at the back when the bus or streetcar turns at Church Street frantically pulling the cord 50 times in a row, thinking that will make the vehicle stop for some reason. Then when it finally gets to the next stop they will walk to the front to exit, then turn around and walk back past the door they could have exited anyway.
I am not suggesting that I like either diversions or short-turns but they WILL happen due to accidents, street closures or schedule problems and my point was that having a couple more options downtown would be good. For 99% of passengers a diversion is much preferred to no service at all!
 

steveintoronto

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Here's the most detailed pic I've found so far on the TransTech Helsinki trams. They're produced by a Swiss company Prose who make bogies for a number of large names in the rail business.

Still looking for technical/engineering description, but already, the 'steerable elements' are clearly visible in the pic, for both axle geometry and drive compliance for that:
https://www.prose.one/fr-fr/News-and-Events/News/Detail?nid=82

Here's some company promo:
https://www.prose.one/DesktopModules/PRO_CaseHistory/files_ch/7-3_000.pdf
https://designenlassen1.s3.amazonaws.com/5/583738/prose_presentation_standard_e.pdf
 

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