Hello again! I'm Becky, and today we're
going to be taking a pressure sensor
into a little inflatable pillow. 
I'll show you what that means. This is a
pressure sensor that I have soldered onto a set of wires, that will be sticking
out of the inflatable form, so that I can
monitor the pressure on the inside, and
make my electric pump respond to it
actively. I have a whole breadboard set
up to use with this sensor, I'm going to
have diagrams on my website,
beckymarshall.com/inflatables.html
(link in the description box below)
but the first thing I have to do is make the
inflatable pillow. I have already cut
my form, I'm just gonna make a simple
rectangle today, but I do have a new tool
to use.. this little squeeze bottle! It's
kind of like an accordion. The other
thing I have that I want to show
you is this giant scepter of vinyl that
I got. This cost, like, twelve dollars! (laughs)
It's so much material! So, I am gonna make
something big. Not today, because 
I'm just testing something with my pressure sensor,
but my next video, you can expect
something big! We'll see what it is.
The other thing that I got that I'm excited
to share: some tubing for my pump! Now
I can inflate more large scale things that
won't be impeded by this little output
right here. So, I'm going to head to the
spray booth, put on my safety gear, and
make this little pillow, with this
pressure sensors sticking out of it like
this! It's gonna be strange. I hope I can
achieve a good seal on it. We'll see
OK. I have my prototype, this time with
wires sticking out of it. I don't know if
it's airtight, but we will figure it out
when we inflate it. So, I'm going to
inflate it with a bit of an on-and-off
motion from my pump, and we will see
first if it holds air, and second what
the pressure sensors say. This is a very
slow inflation... so far the pressure sensor readings are not doing anything
interesting. I'm going to run the pump a little higher.
You know what I just
realized? 
This isn't connected to anything. (laughs)
(hysterical) I didn't replace the pressure sensor ! 
So it was just a fake reading?
Uh-huh.
I'm really tempted to, like, remove
this from the video, but I kind of want
to exhibit my shame.
Sooo.. Okay......
OK! So now, for prototyping purposes, we
have this sensor wired up to
this breadboard.
Let me just make sure I don't pop that.
I forgot to plug it back in
after removing the power! All right. Now
it's having a reading. (confused)There's no
difference in the pressure sensor... hm.
Well, the good news is that my inflatable
is airtight, including where the wires
are sticking out. That is good news. Bad
news is that the pressure sensor keeps
giving the same, neutral reading that it
always has been... which means that there
is probably something not right with the
sensor and the way that I've hooked it up.
So... I'm gonna have to deal with that!
Hello again, it's another day, and I'd
like to follow up with how this squeeze
bottle went. The glue did harden and dry
on the applicator end, and you can see,
though, that it is still viscous on the
inside. So I lost some glue, you can see
it covering this tip, but overall this is
a win and I'm looking forward to using
it again. I'm also going to test this
other squeeze bottle. I think that this
would have been more appropriate for the
smaller scale prototype that I made on
my last go. And here's the prototype. Here
we have the valve, here we have the
airtight seal, and here's my Arduino.
So let's inflate it and see what the
pressure sensor reads!
(shocked) Oh, jesus!
--what the...?
It is reading in the 400s and 500s...
I'm gonna try  it at a much higher rate
Boom! 
OK, so we are getting some
different readings. Let's see what
happens when I push it. OK, it goes down... and when I let go?
... So it's just noise? I do not understand.
OK, what happens if-- it's reading 500,
500, 498, 500, and if I squish it, 496, 495... OK so, it's registering my smoosh... if I let it
go? It's back up to 500.... No, it's back down... it's lower than it's been before...
it's 485... this doesn't make-- it's back
up to 500-- okay, this doesn't make any sense to me.
Alright, I'm going to release it. Mm, there doesn't seem to be any meaningful difference!  OK...
I cannot tell if the numbers are
lowering because I'm smooshing it, or not.
Something that I noticed off-camera is
that, if I punch this inflated pillow, the
pressure sensor gives me different kinds
of readings. So let's smash it up.
So, it is varying wildly from the low 400s to the high 400s.
(Noise of air leaking) Whoa!
Oh wow, it jumped up, it jumped
up to 650 when it came undone unexpectedly, and then I went down to 370! We're
getting a really wide range of readings
on this.
I'm being really mean to my pillow.
If I just let it rest, what does it do...
It rests around 450 now.
What I'm realizing with all this testing
of this pressure sensor, is that I don't
even know what I need the pressure
sensor for! (laughs) So I think I've gotten it to
work as well as it might work, but, I'm
gonna move forward with prototyping
different kinds of hardware. So what I
want to do is, I'm gonna make a large
form next, I'm using my big vinyl roll,
and then I'm gonna make a raft type
project where I'm gonna lash together
several long cylinders of inflated vinyl,
lashed together like a raft, put it afloat
and see how it can bear weight. And I'll
just leave this pressure sensor for...
future experiments. What I am very happy
with is how much I've kept this seal.
This is a perfect seal. So here's the
deal. What you've witnessed today is a
bit of a failure. And if you ask anybody
who's a designer, failure is a big part of design.
The pressure sensor was a lot of hard work to get it working, even this well, and at
this point it just seems like a lot of
noise, and some major insights, but what
I'm gonna have to do in the future is
set the pressure sensor up so that it
doesn't touch the walls of the
inflatable, because I think that might be
introducing a lot of the noise that
we're seeing. I'm gonna wait until later
in the process, to find out how I might
want to use the sensor, to keep working
with it, because this is just taking up
way too much time. I'm comfortable with
failure today. I learned a lot. I'm done
with it. I hope you learned something
from the video today! I'm really curious
to hear how you guys find this video, so
if you searched and found this video
because of a project of yours, please
share in the comments, like, what brought
you here. I really want to hear about
your projects. I'm trying to reach 100
subscribers by the time I graduate, so
please be one of those 100! (laughs)
(Offscreen) Like and subscribe!
Like and subscribe!
If you want to see the breadboard set up for the pressure sensor that I worked with today, look in
the description box below, and you will
find a link to my website, where I have
diagrams and code set up for your use, so you can recreate it.
Cut. 
(offscreen laughter)
Oh, OK.
(offscreen) That is gonna have to be good enough!
