Every Raspberry Pi starts its life on the production line here at the Sony Tech Center in Pencoed, Wales, UK.
I was honored to be invited to share with you an inside look at the high-tech
manufacturing line for the Pi 4 where they've made nearly 50 million Raspberry Pis in the past decade.
Every employee I talked to was focused on making every Pi reliable and efficient and it was
fascinating learning about the history of the factory and how the line works.
[Andrew] My name is Andrew Puntan. I'm a lead engineer for new business development team here at Sony UK Tech
I've been here just a tad over 26 years now. What we say is the—the life of Raspberry Pi, should we say,
this actually begins in our SMT department, which is Surface Mount Technology, and in that area
this is where the actual individual circuit boards get populated. They come in a panel of 9. Each individual circuit board gets populated.
The first part of that process is applying solder paste to the board. That gets done by a screen printer.
So very similar to how many, many years ago and how you'd actually manufacture a book.
The squeegee actually puts the fresh paste down onto the circuit board, then we apply
all the individual components.
Now it's very unique how we apply these individual components.
It's like building a city for example.
We start with the very small houses or the very small components and then build up the
larger components.
[Jeff] The reason they do that is because the heads on the pick and place machine, that gatling-
gun-like thing that spits circuits onto the solder paste, uses a tiny puff of air to jam
the components into the paste. The head has to get really close to the board, like a millimeter
or two. Because of that, they have to put the shorter components down first, then the
larger ones, otherwise the tools would obliterate the larger components while they're spinning
around. [Andrew] So the initial key is, smaller components on the underside of the board, and they get
processed first, then the larger components on the top side of the board, and they get
done last. [Jeff] Employees changed out these component reels a few times while I was there. Right
now, the reel with the SoC at the heart of the Pi—this big square chip—is the major
bottleneck. When they run out, they have to shut down the entire line until they get more.
After the pick and place machines, the PCBs head into the reflow oven.
[Andrew] So one of the key things about the reflow oven is the temperature as it progresses in.
So it's quite a long oven and it starts off at the lowest, sort of the 150 degrees and
then moves up to the 260 degrees. And there's a reason for this. So when the actual circuit
board gets in, if there's moisture in it, we slowly need to remove that moisture from
the process because if we heat it instantly after the highest temperature
you'll get something called 'popcorn' which can damage the parts. The moisture
will get inside the components and they'll burst out. [Jeff] So you could say that
the Raspberry Pis are baked in an oven? [Andrew] Yeah, we bake Raspberry Pis here.
[Jeff] At a few points I saw machines taking tons of pictures of the board so I asked
about them. [Andrew] Through the SMT line as well we have various, we have AOI
inspection which is automatic inspection of individual components. Make sure
everything is placed correctly, correct location, nothing's missing. [Jeff] If any flaw was found the board
was pulled for manual rework. The boards were marked by hand so they could get these boards
back on the line quickly. They have dozens of hoppers of completed boards at the end of the SMT
line and before getting to the next part I asked Andrew about the factory's history. [Andrew] A little bit
of history about the building. It was actually opened when Sony first came here in 1973 and how
Sony came here was now King Charles, met with one of our founder members in Japan, Morita-san.
So this factory where we are in today was actually opened by the Queen in 1992 and this
is now the UK Technology Centre here in Pencoed, South Wales.
So if I fast forward it a couple of years to where we are now, our core products as
you can see behind me here, are broadcast professional cameras, our Master Set Up units,
camera control units and OLED viewfinders.
[Jeff] One of the most visually impressive parts of the line is where the larger through-hole
components are placed one by one by these dutiful robots.
[Andrew] The next stage is where we'll actually apply the likes of the Ethernet ports, the USBs, and headphone jacks. [and pin headers]
And in that part of the process right now we're using collaborative robots to place those components.
[Jeff] A while back this entire process was done by hand by employees.
And some people watching this will probably lament the fact that humans are being replaced by robots.
But look closely at how these robots actually place the components.
That little wiggle you see? [robot does the wiggle] That was programmed in by a human.
Programming the robots requires a ton of back and forth between engineers, line workers,
and the robot manufacturers to get them to work reliably for placing millions of components.
These robots mostly make the line faster. There are still humans loading in component trays,
feeding the robots with the raw parts that go on the boards, or clearing up jams.
The robots increase line capacity and free the humans to do other things better.
Like, look at those GPIO pins. There's a custom hopper that uses only vibration to align a
a relatively complex part perfectly every time.
How cool is that?
But the robots aren't perfect,
and that's why there's always a human
at the end of this part of the line
placing the last few components the robots can't get to.
In fact, I got to see what it takes
to clean up after the robots.
[Jeff, on the line] I've been told that I could try doing this
and see how good I am at it.
[Eliot] No problem.
[Jeff] And try not to make a huge mess at your station.
[off-camera] You've got a body double, right?
[off-camera] Yeah, you have.
Look at that!
(laughing)
[Eliot] He's my brother.
You've got about 27 seconds for every panel.
So you take a seat.
[Jeff] I'm gonna try this out.
[Eliot] So you should only have to put in the four GPIOs,
so these bottom four.
So they're short and down.
You should know.
[Jeff] Yeah, yeah, yeah.
I've put together some of these, you know.
But only like one every year.
[Eliot] So then you've got the five Ethernets there.
[Jeff] Oh boy.
[Eliot] So you've got the two in the middle left.
[Jeff] I heard a beep, I hope that wasn't me.
[Eliot] Yeah.
So once you've done that, it's just a quick sense check
of making sure that all the components on the board,
so obviously you've got the three, the two USBs,
the Ethernet, the four pins, and then you press this button.
[Jeff] I did it!
There's a little bit of a backlog, yeah.
I gotta be as fast as the robot.
[Eliot] I don't know if you've got any other plans, though.
[Jeff] It's slightly therapeutic,
but it's also slightly nerve-wracking
because when you touch it,
sometimes you touch another component.
[Eliot] So the robots are pretty accurate, but not 100%.
[Jeff] And now I know if I need a body double.
[BONK] Whoops.
I'm going to break everything here.
Thank you very much.
[Eliot] No problem.
[Jeff] These employees are an essential part of the line before the final selective soldering
process.
And right before that, I caught sight of the little Sony AITRIOS box.
I wonder what AI they're doing inside there?
[Andrew] The next stage from there, we'll be going through a selective soldering process.
So this is where it gets heated up to around 260 degrees into a process up to I think finally
275 degrees where the solder becomes molten and we apply the solder through individual
jets to the components such as Ethernet and that obviously cools off then and that goes
into a final stage of the process.
[Jeff] This process is a little more directed than wave soldering and it's a critical part of
the manufacturing line.
They have tons of these expensive blocks of pure solder ready to go into the molten bath.
This machine has four giant screws that very methodically dips the board into the bath
and slowly pulls it out, ensuring a perfect connection on hundreds of through holes on
every set of Pi boards.
Oh—and don't drink that!
After the selective soldering, the boards go through a cooling chamber.
Under that chamber, I found one of the 15 or so Raspberry Pis I could find along the
manufacturing line that are building other Raspberry Pis.
Pis building pis!
I even did a video on the Revolution Pi last year, so go check that out if you want.
On the topic of Pi products you could find in a factory, Seeed Studios sponsored this
video and they just launched the reTerminal DM.
It's built around a Compute Module 4 which is also made right here in the Sony factory.
This thing can integrate with Node-RED for low-code programming and event-driven applications.
It has a rugged design with an IP65 front panel and electrically isolated I/O.
It's great for any kind of HMI, from a premium Home Assistant controller to industrial use.
Seeed Studio also offers ODM services.
They can help with everything from product development and R&D to production and support.
Even this re-terminal DM could be customized for your use case.
They're releasing even more new products based on the Pi like this reRouter, a travel router
also based on the Compute Module 4, or their Edgebox line of industrial Pi computers.
Check out Seeed's Raspberry Pi blog for more, and check out the links in the description.
After the boards cool down in this little wind tunnel, they're checked one last time
by a technician, and any little spot that needs a little extra solder gets it.
Then one of the most impressive parts of the line is this, the giant farm of 64 fully automated
test jigs.
[Andrew] They all get individually tested in a bed of nails test fixture, and all of the likes
of the SD card, the HDMI connections, headphone jacks, they'll be automatically connected
as part of a test jig.
Then there will be pass or fail at that stage.
99% of them will be a pass.
[Jeff] And I kept finding more and more of these little boxes, inside of which is another Raspberry
Pi.
Pi is building Pi's all over the place here.
But that brings me to something I sensed as I talked to the Sony employees, and even when
I was discussing how they build Pi's with Gordon Hollingworth over in the labs at Pi
HQ.
Sony and Raspberry Pi worked together to build the test jig, and they even have a manual
version of it at Pi HQ so they can continually improve it.
Like one time they found out if someone loaded a component upside down it would still work,
but not the right way.
So they modified the jig at Pi HQ to make sure it would detect that error, pass the knowledge
to the Sony engineers, and one by one they got all the jigs in the factory upgraded.
Now that problem can never happen again.
And having this kind of tight relationship means when Raspberry Pi discovers new things
in their labs, they can quickly iterate on the manufacturing process to make it better
and better.
Andrew said he's been involved with Raspberry Pi since the very beginning.
[Andrew] I was involved with the Raspberry Pi, the initial introduction, and that was back in
around 2012.
Their values and behavior seemed to match a lot with ours, so we thought, "Let's give
these guys a chance," and you know what? The rest is history now.
[Jeff] How many Pis did they predict that you would be manufacturing initially?
[Andrew] So we thought we were going to be in the 10s of thousands.
This quickly increased, and I think by 2013, we'd actually manufactured our millionth Pi.
Where we are today, this year we're aiming to hit our 50 millionth Pi.
[Jeff] One line that looks like it's changed a lot from the older videos I've seen is the packing
line.
It's 100% automated and full of clever engineering tricks.
[Andrew] I'm privileged to be one of the members who actually developed that stage of the process
and who's effectively a year of our lives.
So we've done some exploratory work in how people are packaging processes in the food
and drink industry, in the pharmaceutical industry, and we've developed it into our
process here.
How we've done that is we've minimised how we deliver the boxes in so they all become
flat packed.
We actually erect the boxes here and they're automatically glued into a punch machine.
Once that punch machine goes into an indexing conveyor, the actual boards, the manuals and
the individual instruction cards are placed into them.
Then we automatically place the Pis on top.
Then they will go through a final stage which is a mechanical means of closing it and gluing
the box. [Jeff] And I wanted to spend a little more time on this part of the line
because it was fascinating. So many different noises and motions I could
probably spend half an hour mesmerized by any one part. But this little robot, it
picks up a tested Pi off the line and holds it over this little scanner. The
scanner checks it out and if everything's good, into the box it goes.
Then as the Pis come out of the machine this little piston does what it does. It
used to help align the side flaps, then it kept things tucked in the box. I love
this piston because it's a reminder of how this line evolves over time, and because it
still tries its best no matter what.
Then there's another quality assurance test, a camera that takes a picture of each box
before it gets sealed up for good.
You can see that each time you see the flash.
Then this fun machine shuffles the Pis over to the final line, where some of the cleverest
engineering results in a nicely closed box.
The metal flap in the middle holds the side flaps down, while a metal bar slowly presses
the lid down.
The blue box squirts a couple blobs of glue on the outside.
Then one more metal flap bends down the lid, completing the packaging process.
[Andrew] At that stage then we'll actually weigh the box to make sure all the individual components
are fitted.
Then they will be selected at the end of the process to be packaged into the box.
So you'll get 150 into a final box then for shipment.
[Jeff] That last little check measures the box's weight to the gram.
If anything is missing, it'll pop the package out.
But I love this little 3D printed flapper that swats the Pi along on its way if no other
Pi comes along to push it off the scale in time.
There we go.
[Andrew] Then we automatically pack them, place them into the box, and get them shipped out to
a warehouse.
[Jeff] At the end of my day at the factory, I waited for one more box to roll off the line.
[waiting... then with great enthusiasm:] Yay.
Normally, a worker would tape it and stack it, but they let me hold one of the thousands
and thousands of Pi's they made that day—at least for a second.
[Andrew] We produce these Pis in a quantity of 180,000 to 200,000 a week
Right now we're producing Pis—what we say is "every 3.14 seconds"
[chuckles]
[Jeff] And that's just the Pi 4.
The factory was making Pi 3B+, Pi 0, and even some CM4 and CM4S while I was there.
Have you ever thought about building an automated test jig for a CM4?
It's hard, but Sony has one.
And just like with the Pi 4, the CM4's test jig has another Raspberry Pi hiding inside.
There's also the CM4S, which is a child of the shortage.
I can't imagine the pain some engineers had to go through building the automated test
jigs that can survive thousands of insertions of basically what amounts to a stick of RAM.
[Andrew] So when we initially started our conversations with the guys from Raspberry Pi, it was very
quick to understand that we shared the same values and behaviors, all about inspiring
the next generation.
And where we are today, we continue to inspire each other to drive things forward.
[and all watched over by machines of loving grace]