DEYSI: Today these engineers
are going to use the design process
to build something. The design process
is a set of steps that engineers, inventors,
and other creative people use to come up with a solution. And this is the Acera School. Acera is a school where kids
can work with their hands to solve problems. The first step in the design
process is to define the need. Say you're at, like,
the grocery store, and you're biking, right? And then it's really hard
to hold your groceries, because you're doing this. So you have to use something
that will make it easy to have it in the back. I guess we could put
the groceries in a trailer. DEYSI: It's easy to skip past
defining the need and rush into
design and building. Who's going to use this trailer,
and what are they going to use it for? Well, I'd be able to use it,
and my parents probably would. If you don't define the need,
it's hard to come up with solutions that work. - We could make it so it holds
multiple things at once. Defining the need paves the way
to fulfilling the need. So what's the next step? Brainstorming. DEYSI: Once an engineer or
inventor understands the need, it's time to brainstorm
to generate ideas and come up with solutions. - What if we had a separate
little area in the cart that was padded,
so we could have eggs and other stuff like that
that can get broken? I think that's
a really good idea. We could use
pressure-treated wood. Wood might be
a little bit heavy. Aluminum? That's what the bikes
are made of. We can't really
weld aluminum together. We might be able to use
PVC pipe. Yeah, PVC pipe, it's very light,
it's going to be strong, and it's not going
to fall apart. - And also you can change
the design because there's so many different sizes of it. DEYSI: Brainstorming is
about quantity. The more ideas, the better. Maybe there's something
that's already kind of like this that we can repurpose
and make it into a trailer. - You found a trash can. The next step is to design. Looks like we have two ideas. One is a trailer
made out of PVC, and two is a repurposed
trash can. Designing involves
sketching out your ideas, narrowing down your solutions,
and giving it the NUF test-- is it new, useful, and feasible? It's new, because I don't think
anyone's ever made a trailer out of a repurposed trash can. It's useful because you can
carry groceries in it. And it's feasible because
we're actually building it. DEYSI: The next step
in the design process is actually three steps
that cycle around, and may be repeated--
build, test and evaluate, and redesign. - We decided to work on the
repurposed trash can idea first. - Almost. Yes. DEYSI: Yay, good job. The trailer would bump into
the bike wheel, so we can use this shopping cart
as a connector between the bike
and the trailer. We already have the rack on it. - We attached the shopping cart
to the rack with two zip ties, and then we tested it. The cart was not turning--
it just stayed straight. Failure offers an opportunity
for improvement. It's what makes designs
better and better each time. - So we redesigned the
connection using zip ties and a carabiner clip, the kind
that's used in climbing. Now the trailer pivots. DEYSI: This is the heart
of the design process-- the cycle of testing,
evaluating, redesigning, and then repeating the process
until the design is successful. - Now we are starting work
on our PVC pipe design. - Elliot measured
some grocery bags, and then he made
a scale drawing. - A scale drawing is when
you make a drawing to the size of the actual thing
you're making. - So I'm taking the measurements from the drawing
that Elliot made and marking them down
on the PVC pipe. This is PVC pipe,
and these are PVC fittings. The PVC pipe is designed
to fit into the PVC fittings. By using different
lengths of pipe in different fittings,
you can make lots of different designs. - This is the basic box
of our trailer. These are two lawnmower wheels
that I found in my basement, and I thought might be useful. I'm going to put this axle
through the caps that Grace and Elliot
drilled holes into, and then I'm going to
put the wheels on the ends. Wow, that looks good. What we can do is we can
take the nut off, and then attach something to the nut. I'm going to cut this
piece of metal with a hacksaw and then drill a hole
into this piece of PVC pipe and attach it. That's good. All right, let's try it out
and see if it works. - I was running
behind the trailer, and I saw it would rub against
the wheel of the bike. I think we need
a redesign here. So I made an angled tow bar
so it won't drag against the wheel. So this is a hammock
that I designed to put eggs in. I used paper fasteners
to attach the inner tubes to each other. This hammock will help
suspend the eggs so that they won't hit the sides
or fall out. A lot easier to carry. I'm heavier than
three bags of groceries. Nope. I think he's enjoying it
a little too much. This is awesome! The final step
in the design process is sharing your solution
with others. - I think that the trailer
that was made out of the trash can right now is a little bit
more sturdy. - But it was bulky,
it had a wide turning radius, and it didn't have, like,
a way to keep eggs safe. - But I liked the PVC pipe one
better. Yay, my eggs are safe!
