'Every millimetre counts': Inside the beast tunnelling under Sydney Harbour | Hacker News Reader

'Every millimetre counts': Inside the beast tunnelling under Sydney Harbour

smh.com.au

11 pointshiharryhere10 comments

Thank you.

I'd never thought about it till a knee jerk scoffing at the title:

But do they need the TBM to be milimeter accurate the whole way- or do they just need mm accurate surveying and very high accuracy when merging the tunnels?

It might seem inane- but they're two VERY different things.

My guess - a bunch of lasers, levels.. maybe some compasses... sufficiently precise instruments to gauge distance, heading, and travel-path from known above-ground reference points.

A boring expert could talk all day about it :)

Interesting to a see a Windows 7 machine in the picture captioned "Andrew Jones in the boring machine’s control room."

A lot of industrial and scientific instruments/equipment require a computer to run them, gather data, etc.. Often the software on that computer is Windows based and, if it is, you're not going to connect it to a network (if you can avoid doing so) or use it for anything but running the hardware. OS and software updates are not going to be installed because they'd require software updates from the manufacturer that may simply not be available. e.g. There are still a lot of labs out there with several computers running Windows XP because that's the most recent OS supported by drivers for some very expensive kit.

There are still sites running Windows NT on their critical control systems for the same reason.

>The 6.5-kilometre motorway is due to open for traffic in late 2028, easing congestion on a key part of Sydney’s road network

For people interested in the background planning behind this, here's the video showing how it was done: https://www.youtube.com/watch?v=LTCZZBrhORs

I used a MS-DOS analyzer until 4 years ago. The Win7 version of it [1] is worse in every way.

[1] https://www.stago-us.com/products-services/hemostasis-system...

Yay for the metric system!

Right? 1/32" precision would have set the bar way too high!

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