[HN Gopher] London's Crossrail Is a $21B Test of Virtual Modelin...
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London's Crossrail Is a $21B Test of Virtual Modeling (2016)
Author : edward
Score : 68 points
Date : 2021-07-31 07:40 UTC (15 hours ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| monkeydust wrote:
| Impressive implementation of a digital twin. Looking forward to
| finally taking a ride in this thing when it opens.
| notjustanymike wrote:
| This should finally validate hacker movies that do a swish 3D
| fly-by of the bank/casino/high-school they're breaking into.
| flancian wrote:
| (2016)
| dkdbejwi383 wrote:
| Is that the original opening date for the line or the article
| publication date?
| DrBazza wrote:
| Announced this week that they're aiming for Feb 2022.
|
| https://www.ianvisits.co.uk/blog/2021/07/27/crossrail-
| aiming...
| caffeine wrote:
| I think this is a (good) joke, but just in case - the
| article.
| bambax wrote:
| Indeed. From the article:
|
| > _The first Crossrail trains will start running in 2017, and
| when the network is fully open in 2019, it will shuttle an
| estimated 200 million passengers every year._
|
| Currently the project hopes to be able to open one line in 2022
| (maybe) and is at least half a billion pounds over budget.
| Symbiote wrote:
| That is a pessimistic spin on things. They're opening the
| final part of the line (the new tunnels), they're confident
| of doing this in February, and there's a clear plan on how
| the rest will open in stages in the following 12 months or
| so.
|
| https://www.ianvisits.co.uk/blog/2021/07/12/crossrail-to-
| mak...
| tomatocracy wrote:
| This is true but we've been here a couple of times before
| with Crossrail though so it might be sensible to take what
| they say with a pinch of salt - eg in late August 2018 they
| announced a surprise delay in opening from December 2018 to
| late 2019 then in April 2019 that became late 2020/early
| 2021 (which obviously then didn't happen either) - and that
| was all after it had already been delayed from its original
| 2017 planned opening.
|
| And bear in mind that the tunnelling work was completed in
| 2015. It's been an absolute travesty.
| scoopertrooper wrote:
| Well, in fairness the events of the last two years have
| probably caused delays to many infrastructure projects.
| jl6 wrote:
| Only half a billion? So 2% over budget? That sounds great for
| an infrastructure project.
| DrBazza wrote:
| According to wikipedia, at least, it's 4bn [1] But you're
| correct, for a (UK) infrastructure project that's actually
| pretty good especially considering it has to go underground
| through a city that has medieval and Roman ruins littered
| all over the place [2]
|
| > The total estimated cost has risen from an initial budget
| of PS14.8 billion to PS18.7 billion, as of August 2020.[7]
|
| 1. https://en.wikipedia.org/wiki/Crossrail
| https://www.theguardian.com/uk-news/2020/aug/21/crossrail-
| de...
|
| 2. https://en.wikipedia.org/wiki/London_Mithraeum
| londons_explore wrote:
| It isn't done yet... To really see how far the budget
| miss is, you have to wait for the thing to be finished
| and all costs accounted for, while also seeing how much
| the project has been scaled back (for example travel time
| goals not met because the trains are poorer performance
| than initially specced)
| tialaramex wrote:
| Class 345s were all manufactured and are already in
| service today. Is their performance in fact "poorer than
| initially specified" ?
| londons_explore wrote:
| I guess you'll see next year when the timetable is
| released
| sgt101 wrote:
| Filled with tumbleweed (except there is no tumbleweed in London)!
| riedel wrote:
| Damn, they forgot to integrate people into the model?
| loufe wrote:
| Can anybody here give a quick overview of why there are such
| delays for the line opening?
| crocal wrote:
| Crossrail is legendary in the field as the example of what not
| to do when managing mega projects.
|
| What I was told by greybeards: systems engineering was non-
| existent and rushed to the << let's start to concrete >> phase.
| When the project started to install the various systems, all
| hell broke loose. For example, systems had to be taken in, then
| out, because they just didn't work in the field.
|
| Side note: which makes this article really a good laugh. Who
| cares if your virtual model works if it does not in the real
| world?
|
| OK so, that would not have been too bad if the management of
| the mega project would just have recognized the fuck up and
| declared delays. Instead, it scrambled to find ways to
| recuperate the accumulating delays, while reporting green to
| the politicians. As usual, a cretin came into the room to
| suggest that signalling tests could be compressed down and
| commissioning tests could proceed while construction completed
| the remaining work.
|
| Problem: crossrail decided to experiment with a new hybrid
| signalling system that uses two different types of train
| control in order to maximize throughput in central london area.
| That turned an already rotten idea into an impossible one.
| Situation in the fields became insane. Signalling contractor
| shot a letter to cover ass. Politicians finally noticed, and
| sent clueless consultants to investigate, therefore opening the
| gates of hell.
|
| Aaaaah. I like the scent of Napalm in the tunnels.
|
| EDIT: typos
| ArchitectAnon wrote:
| I've worked on some mega projects as well, and the key to
| being on time and on budget is to manage the PR so that no-
| one knows when it's supposed to be completed and how much
| it's going to cost. The only difference between Crossrail and
| private sector projects is that there is no press scoutiny
| over how much over budget they have gone and how late they
| are.
| davidgerard wrote:
| (2016)
| Reason077 wrote:
| > _" The first Crossrail trains will start running in 2017, and
| when the network is fully open in 2019, it will shuttle an
| estimated 200 million passengers every year."_
|
| We're half way through 2021 and still waiting! According to the
| latest project update, "Crossrail Ltd plans to bring the
| Elizabeth line into passenger service as soon as practically
| possible in the first half of 2022."
| tsywke44 wrote:
| Who cares? These are rail lines which will be used for
| centuries. Trust me, nobody will even remember a few years of
| delays.
| moeadham wrote:
| I think a lot of people care.
| Joeboy wrote:
| I care - I chose my new flat partly based on its proximity
| to a Crossrail station. Nevertheless I'm optimistic that
| the delays will seem like historical trivia in a year's
| time.
| edent wrote:
| No one using the Jubilee line today cares about the
| construction delays.
| radycov wrote:
| What churlish asinine myopia. Plenty of people affected by
| life changing disruption to their living conditions and
| communities. Seveal years of putting your life on hold is a
| big deal.
| throw0101a wrote:
| > _Trust me, nobody will even remember a few years of
| delays._
|
| I remember someone commenting that given the choice, it's
| better to delay shipping video games if you need to fix
| things. This is because not long after release no one will
| remember it being late, but everyone will remember (hearing
| that) it being a pile of garbage.
|
| Reputations are often very hard to shake.
| user5994461 wrote:
| That's not true anymore with online updates and early
| access on steam.
|
| You can ship a game with lots of bugs and missing content,
| as long as the price is set in consequence.
| ksec wrote:
| You only have _one_ chance to make a first impression.
|
| - Someone.
| DaedPsyker wrote:
| I think there is only so far you can stretch that before
| reputational damage is too great. I've seen early access
| games effectively abandoned as result.
|
| The soon to be classic example is cyberpunk. Funny this
| actually happened to them before with the first Witcher
| game, originally very buggy and had a re-release that
| patched it, but they were a smaller studio then and their
| reputation effectively unknown.
| user5994461 wrote:
| You need to put that in context. Compared to a decade or
| two ago, an initial release was printed on DVD and
| unpatchable, a buggy game was effectively plastic waste.
| If it weren't bad enough, reviews and magazines would
| demolish it and make sure there were zero sales later on
| (not that there was a lot usually because most sales
| happened right after release).
|
| It's an incredible progress for game developers that they
| can ship a buggy/incomplete game and improve it over the
| next year. (And you can write an announcement with every
| update to drive sales!)
| superdisk wrote:
| Shigeru Miyamoto said that actually.
| Reason077 wrote:
| > _" Who cares? ... nobody will even remember a few years of
| delays."_
|
| If project timelines and budgets are not credible, it has
| very real implications for the viability of future
| infrastructure projects. It becomes much harder to justify
| future spending if you can't trust your models.
|
| Already (before than pandemic hit) the blow-outs on Crossrail
| were putting the north-south "Crossrail 2" line in doubt.
| Originally it was hoped this would get started in 2023, but I
| doubt there's any chance it will start before well into the
| 2030s now.
| user5994461 wrote:
| COVID and Brexit have drastically reduced the amount of
| commuters, for the foreseeable decades.
|
| Don't be surprised that $20B transportation projects are
| being reconsidered.
| toomuchtodo wrote:
| The best capital improvements are the ones that you can
| obviate away through cheap behavioral or societal
| adjustments (just as the best line of code is the one you
| can remove or didn't have to write).
| Swenrekcah wrote:
| These words aren't necessarily wrong, but quite
| irrelevant here, since Brexit can be called many things
| but 'cheap' isn't one of them.
| toomuchtodo wrote:
| Was more directed at COVID pushing remote work, negating
| the need to shuffle bodies around via public transit to
| do knowledge work. I agree Brexit has been an expensive,
| unnecessary shit show.
| QasimK wrote:
| COVID has not been cheap either - it has cost hundreds of
| billions [0]. You could fund twenty crossrails for this
| amount of money.
|
| [0]:
| https://www.theguardian.com/business/2021/mar/22/a-year-
| of-c...
| toomuchtodo wrote:
| Brexit was a choice, the fiscal/monetary response to
| COVID was necessary and unavoidable.
| Schiendelman wrote:
| Project timelines and budgets for projects of that size
| have never been predictable. Look at software development,
| the industry has largely moved away from trying to predict
| large projects and now just builds the smallest increments
| possible. Building infrastructure in a city with 100,000
| unknowns underground is far worse.
|
| Seattle had the same hand wringing around our newish rail
| line back in the early 2000s, now no one even knows it was
| late.
|
| Also - Now that Seattle is around 85% vaccinated, offices
| are re-opening and the trains are full again. London is
| being more conservative in their approach to reopening, but
| they are merely months behind.
| Reason077 wrote:
| Trains are pretty full right now in London.
|
| But just "full to capacity, standing room only" full, not
| "full to beyond capacity, have to push and squeeze your
| way in before the doors close" like before the pandemic!
| neverminder wrote:
| People who bought their houses along the line expecting
| speedy commute care very much.
| detritus wrote:
| Well, in the context of the linked article and hence the
| comments here, it seems relevant to mention the fact - 5
| years after the article's publication - and to consider
| whether the reliance on comprehensive digital modelling might
| be in any way to blame for the delays?
| neRok wrote:
| > consider whether the reliance on comprehensive digital
| modelling might be in any way to blame for the delays?
|
| Maybe. 3D models have been used to design and plan projects
| for over 20 years now (I've been in the industry in Aus for
| >15 years), and so the bulk of the models are not at fault
| here (because if these design models were the delay, the
| construction would also be delayed, but the article
| suggests it wasn't). But when you want to go to the next
| level (digital twin), and start modelling every individual
| light-bulb, tracking it and making it function as part of a
| "smart system", then things will take a lot longer.
|
| But actually, the article says;
|
| > Despite the huge amount of construction work that has
| already been completed, many aspects of Crossrail do not
| yet have an agreed-upon final design. That's because the
| complexity and uncertainty involved in building large
| underground structures means that detailed "fit out"
| designs are begun only after it's fairly clear how the
| space will look.
|
| This boggles my mind. I don't see how it couldn't all be
| completed at the start. The physical design should have a
| few flexibilities baked in, so that if the tunnel ends up a
| meter out of place, or the rail centerline is 200mm off
| target, the design should be able to absorb it with minimal
| re-work.
|
| But regardless of the physical layout, they could have
| mocked up a model beforehand that contains all the
| necessary "virtual" components. They would have known what
| rooms/etc were required, roughly how many entities were
| needed per space (eg, 4 chairs, 1 table, all with data
| tags). Then when you have a better idea on the physical
| layout, you can arrange the virtual components properly.
|
| So yes it's possible that trying to be too fancy was a
| major factor in the delays. I haven't worked in a
| professional software engineering environment, but I get
| the impression that at a high-level, construction
| engineering has similar traps and pitfalls. Just like when
| coding, engineers/modellers do come across problems with
| their initial design, and then have to face the choice of
| implementing significant work-arounds, or "refactor" to
| something different.
| p_l wrote:
| A big issue with digging under London is that you never
| know what you'll find
| 7952 wrote:
| I have worked on major construction projects and a
| complicating factor is the sheer number of different
| disciplines involved. Teams work with their own systems
| and maintain their own state and then inexorably get out
| of sync. In computing this kind of thing is understood at
| a more fundamental level. You have locks, transactions,
| branches, merges, continuous integration etc. These same
| problems exist when designing a major project but are not
| understood.
|
| Information systems exist but seem to have shocking data
| models designed by committees. Existing software and
| experience is then transposed on top of this information
| system. But the engineers don't have expertise in data
| and are using software from another age that makes
| "drawings". Adding a live "as built" component to that is
| just asking for trouble.
| dang wrote:
| Discussed at the time:
|
| _London's Crossrail Is a $21B Test of Virtual Modeling_ -
| https://news.ycombinator.com/item?id=11562799 - April 2016 (11
| comments)
|
| _London's Crossrail Is a $21B Test of Virtual Modeling_ -
| https://news.ycombinator.com/item?id=11378752 - March 2016 (1
| comment)
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