The alternative is hiring a consultancy that may or may not actually deliver anything worthwhile at the cost of many thousands a day and leaving you with a solution that you cannot maintain because you completely lack the internal compentence because you outsourced all of the development. More small/medium sized businesses should take risks like this.
We should honestly be questioning, esp in the UK, the degree to which we depend upon consultants for seemlingly everything and how little businesses and government are willing to invest on taking in small bets on their own employees over hiring frankly overpriced consultants from Accenture or McKinsey who are often expensive suits backed by a bunch of very recent graduates with little or no experience.
But a part that's missing is the reason WHY companies often prefer to hire inefficient outside consultants that will under deliver, over promise, and often leave you with a half functional system at the end.
It's for class politics and control reasons that managers and executives don't want to invest in on-site talent to expand their skills. They want disposable labor even if it costs them more money in the end, because it's a decision motivated by their power interests. They don't want to depend on on-site talent, they don't want to promote you, they don't want to pay you what you are worth, they don't want your talents to develop.
They want to pay an outside agency whatever amount of money for the promise of a system, because even if the consultant fails they have fulfilled their capitalist due diligence and did things the right way, rather than having had local employees that are crucial to you that you invest in do work for you.
If you take issue with this characterization, I'd ask you why do many people here find it notable that this company had an existing employee develop a system rather than just dragging in the consultants.
They are parasites on both the private sector, public sectors, and even government policy development. I actually suspect its corruption more than classism.
I am speaking as someone that used to be one of those pink face graduates behind the expensive suits that was horrified at how hollowed out so many of our publically traded companies and government are.
Exactly the same thing happened in the 80's with personal computers. Suddenly you didn't need to wait for the accounting department to write their purchase order after 'their' sales department had - reluctantly - come to an agreement with 'your' bean counters about what the budget was and how you were going to have to do with less of what you needed but more than what they really would have liked to give you.
A RasPi fits within any discretionary spending budget, there likely isn't even a write-off on them, it's just booked as costs in the year it is expended. And associated bits and bobs for sensors and actuators will be bolted on as needed.
In the end it may not be the best or the cheapest solution but "now" beats "someday" in many industries. I personally see this as exactly the reason why Brompton is the breakout success that it is: they show adaptability rather than to play by the book.
Your point about the cost is right but you have to ask where the cost is: some guy spending two months working out how to interface a Pi to something or this being canned and your ask being process modelling. At the same time that guy is then upskilled in fairly generic automation which can be used at other levels across the business. It's very easy to write off unproductive uses of employee time.
Brompton is a success but I'm not sure why. The bikes are by far the most horrible thing I've ridden other than the Sinclair A-bike. I'd rather walk.
I don't know if you've worked in industry, but companies actually won't invest in their local employee to get trained on 'industry standard' automation hardware. They contract that out. So you have no one on site who knows how anything works, half the time. The choices are often "pay s ton and have all the traditional investment of time in a contractor setting up PLC hardware and finding external software integrators to do all the other actual useful stuff you want, or just don't do the project because all of that is expensive and resource intensive."
I have worked in the industry and it has been a mix of in-house and hired cabinet chimps.
If you have the time and money to work out how to interface a Pi to GPIO and write a software front end, you have the time and money to buy a PLC and integrate that with a COTS HMI front end.
That's a pretty strong unqualified statement. I disagree. There are lots of ways in which a little Unix SBC can find a role in industry, lots of that is non critical but very useful, such as impromptu data logging and visualization. I agree that a Pi is far from ideal but but the time you have an industrial computer with the same specs as a Pi you're looking at a massive increase in cost and that may mean that the whole thing gets canned. Something is better than nothing. The 'interface' to a Pi is usually a solved problem in that you can just attach a bunch of pre-cooked stuff to it. And some of the industrial Pi models are surprisingly well hardened. There are literally 10's of thousands of Pi's chugging away happily in various guises in all kinds of machinery. I have worked 'in industry' as well and I don't have any holy houses. It either works, or it doesn't and then it gets replaced.
https://www.onlogic.com/industrial-raspberry-pi/
https://chipsee.com/product/epc-cm4-070/
And so on. These range from 'just pretty packaging' to 'opto isolated IO + stable built in supplies'. Once you have stable power, isolated IO and good storage (all three are known causes for problems when you take stuff into harsh environments, and the Pi is pretty critical when it comes to dealing with these) you are still lightyears ahead of where you'd be with anything the competition fields with respect to available interfaces, development environments, display options etc etc.
Compared to your average Siemens, Omron, Allan Bradley, ABB or whatever floats your boat's toolchain the Pi rocks, you have access to pretty much all of Linux. The biggest problem with Pi's is availability (but even there: all manufacturers have had their issues on that front too).
Anyway, long story short: let people do what they think is right, if they get it to work reliably and affordably then so much the better. Industrial automation hardware has always been ridiculously expensive and underpowered for what it offered, some disruption certainly won't harm them.
Point being there's almost absolutely no reason why they should have used a raspberry Pi in this environment. They have poor power management, EMI resilience, terrible enclosures as a rule and are somewhat prone to fucking out spontaneously with things like SD corruption. Your warranty and service options are basically the trash can. If a station goes down, what happens to your line? The entire cost-benefit analysis is probably wrong here. If it were me I'd buy one of the cheap Lenovo industrial mini PCs and get 5y NBD warranty, actually tested Ubuntu support, without all the other issues and buy an extra one.
They have the cash sitting around to do this properly.
Incidentally also none of this is really special. We were doing exactly this with recycled PC desktops 25 years ago running stuff in VB6 on windows NT on much larger and higher revenue and audit-heavy engineering lines.
The software is a separate issue. Buying that in is usually expensive and problem-ridden.