At the risk of being reductive, I think that under the common law, contract terms are usually interpreted objectively unless they are ambiguous, in which case you might consider extraneous evidence. Clear language is enforced as written.
Unless there is documentation that both parties understood the agreement to be something other than is in the contract, or if it's clear that there is a clerical error. For example, prior emails that show different numbers or a hugely under/over market numbers.
What I find most interesting about the computer side of traffic signal controllers is the interlock design needed to prevent a glitch or memory fault from activating conflicting phases at once, eg two intersecting approaches getting green simultaneously. That's about as safety-critical as it gets for a piece of everyday infrastructure. Would've liked to see more depth on that, though I imagine the specifics are controller/vendor-specific.
I think that interlock design also goes some way toward mitigating the security risks ASCT systems would otherwise pose, as mentioned in the article. On any decent controller, even the control room shouldn't be able to deliberately trigger conflicting phases.
A typical signal cabinet has a conflict monitor, also called a malfunction management unit, that’s physically distinct from the controller. It supervises the controller outputs and can force the signal to all-way flashing red if green (or yellow or WALK) is shown for conflicting phases or if red or DON’T WALK is missing. More sophisticated units can also detect problems with sequencing or change or clearance interval timing.
Country of origin doesn't tell you much on its own. Linux is American too, and few question its trustworthiness. What matters is the code being open source and auditable, not where the maintainers live.
"Linux" doesn't keep centralized records that the government can get their hands on. The fact is that the government in the US can (and does) march into US companies and demand access to their data. The government will install their devices on the company's network and even take over entire parts of their offices. What your data sits, who has access to it, and what kind of record the local government has of abuses of their authority are very important things to consider. Much more important than if the code is open source.
Hah, my dad made something like this for me when I was a kid using a weed eater engine, with a makeshift lever as a clutch to engage/disengage it. This looks about as makeshift, I wouldn't trust it for serious use.
