Lesson video

Hello, thank you for joining me for your Design and Technology lesson.

My name is Mrs. Conway and I will be guiding you through your learning today.

So today's lesson outcome is I can use air to create movement in prototypes.

And these are our keywords: pneumatic system, input and output.

I'll go through each one of these as we work through the lesson.

So the first thing we're going to look at then is looking at simple pneumatic systems. Now, air is all around us.

It's an invisible mix of gases that we breathe.

Now, we can't see it or hold it in our hand, but it can be useful in lots of different ways.

Some products need air to make them work.

So things like swim aids and inflatables, leaf blowers and bicycle tyres are all examples of products that need air to make them work.

Now, air can be squeezed in or blown out of them.

Inflatable products have air squeezed into them by a pump, such as bicycle tyres, footballs, and bouncy castles.

So we use a pump to inflate these products.

Hand, foot, and electric pumps all force air into the inflatable product.

Now, when air is forced into a balloon, for example, either from your lungs or from a pump, it inflates, which means it fills with air.

And the balloon then expands; and expands means it gets bigger.

Now, the balloon can expand because it is made from a stretchy material.

And you can see in the picture there that balloon being pumped up using a hand pump.

Okay, quick check for understanding on that then.

True or false? A balloon deflates when air is forced inside.

Is that true or is it false? Pause the video here, just to take a moment to think about your answer.

And the correct answer, it's false.

Now, to deflate means to release or remove the air.

The balloon inflates when air is forced inside.

Well done if you got that right.

Now, air can be used to create movement and it's often used to move parts of machines.

So we've got an example of a machine here, and this is a digger.

Now, air can be used to move that massive arm at the front of the digger.

A pneumatic system is a mechanism that's using moving air to make things happen.

Let's have a closer look at this word pneumatic.

It looks like it should be p-neumatic, but it's actually said pneumatic.

So the P is actually silent.

The first part of this word, pneuma, that word comes from an ancient Greek word, which means to breathe or air.

Now, pneumatic systems can be found in lots of products such as buses, trams, and also train doors.

Things such as the height adjusters on some desk chairs.

Tools such as paint sprayers and jet washers, and also roller coaster brakes use pneumatic systems as well.

Now, the one you might be most familiar with are those height adjusters on certain chairs.

If your parents maybe have a desk chair at home or somebody at home, maybe an older brother or an older sibling, might have a desk chair that has a pneumatic system in it.

And when you pull or push or squeeze some of the actual kind of triggers underneath, the little handles underneath the chair, the chair might go up and down.

And you might have played around with that a few times, maybe just to annoy your older brother or sister.

Now, air can be used to lift very heavy objects, such as the example of the digger and the big arm on the front of the digger.

Here's a different example.

Now, air is being used to inflate a cushion underneath this car.

So if you look very carefully, under the car, in between the two wheels, you can see there's a black cushion.

Now, that isn't a normal cushion, that's not something that you would have on the sofa.

That cushion is actually being filled with air, and as it happens, it's inflating and expanding in size.

And that means that what's eventually gonna happen is the car is actually going to lift up and it's gonna come up off the wheels.

Okay, quick check for understanding on some of this then.

Which word is used to describe a system that uses air to make it work? Is it A: automatic, B: pneumatic, or C: dramatic? Pause the video here, just take a moment to think about your answer.

Did you get it right? It was B: pneumatic.

So the word to describe a system that uses air to make it work is pneumatic.

Well done again if you got that right.

Now, we can make a very simple pneumatic system actually using these resources.

So things that we would need: a clean, dry, plastic bottle.

Now, good examples of these are washing up or sports bottles with small nozzles.

The small nozzle ones work the best.

A balloon.

30 centimetre length of plastic tubing, and again, four millimetre or five millimetre works best.

And also some sticky tape.

Now, steps to make the simple pneumatic system using a bottle and a balloon are as follows: So the first step then is to attach the tubing to the nozzle of the bottle.

Once you've kind of pushed it and you have to kind of force it over the nozzle, you can then use tape, the sticky tape to secure it in place.

You're then going to attach a balloon to the other end of the tubing, and again, you can use tape to secure it as the balloon opening will be bigger than the actual diameter of the tubing.

So you'll need some tape to wrap around that to get a nice, tight seal on it.

You're then going to squeeze or pump the bottle.

And what you will see that will happen is the balloon at the other end of the tubing will inflate.

These pupils are using their simple pneumatic system to lift some objects.

So we've got Izzy and we've got Alex here, and they've got that simple pneumatic system that I just took you through with this squeezy bottle.

And when that squeezy bottle is squeezed by Izzy, the air is going to be forced down that tubing.

The balloon is going to expand and inflate.

And Alex at the other end has got the bear there.

That little bear is going to be raised up, so it's going to actually be lifted.

Alex has just explained here, "It takes more effort to lift the teddy than a pencil.

I wonder how much more weight we can lift?" So he's noticed that trying to lift a pencil is a little bit easier than trying to lift this teddy bear.

But he's wondering, "Okay, so how much heavier can we actually go here?" It's gonna be over to you now, to have a go at a task.

I'd like you to follow the steps to make your own simple pneumatic system.

You're going to be using the materials that I explained to you before.

So a plastic bottle, a 30 centimetre length of four or five millimetre plastic tubing, a balloon, and some sticky tape to seal those joints.

Once you've made your simple pneumatic system, I'd like you to then try lifting different objects with it.

Start with the lightest thing, and then build up the weight and see how heavy you can actually go with your pneumatic system.

Okay, pause the video here to have a go at these tasks and good luck and enjoy.

Okay, so how did you get on? What was the heaviest thing that you could lift? Now, Izzy and Alex tested different objects and Alex has explained here.

"We managed to lift a book, but it was quite hard.

We had to pump the bottle really hard to get the air in the balloon to lift that." So quite a heavy weight.

Did you manage to lift a book or something heavier even? Okay, next we're going to look at identifying input and output.

Now, lots of systems have an input and an output, but what does that mean? So an input is the way a system starts.

So for example, if you move the joystick on a games controller, that is an input.

You are putting something into that to start it.

An output for that is what happens as a result of the input.

So for example, your input is to remove the joy, sorry, is to remove the joystick on the games controller.

The output is then for the character in the game to move.

Now, simple pneumatic systems can be made using plastic syringes for the input and output.

So we can see here we've got one plastic syringe where we're actually pushing air into it, and that is the input.

The other end of the plastic tubing, we then have an output happening, and that output is the other syringe is actually being pushed out.

That's because the air is forcing it out.

So a plastic syringe replaces the plastic bottle as the input in this example.

It's very similar to that plastic bottle setup that you had a go with, but this time it's using a syringe instead of the bottle.

And the other syringe is just replacing the balloon as the output.

So if we have a look at what we made before, the plastic bottle was the input, the balloon was the output.

In this example, we have a plastic syringe for an input and another plastic syringe for the output.

Now, these simple pneumatic systems can be used to create moving toys, and we've got some lovely examples here of some moving toys that can use pneumatic systems. Now, have a little look at these.

Can you see what they've all been made out of? You might be able to spot it.

So separate components, which are parts, can be made to move by directing air from one device, which is the input, to another, which is the output.

Now, this can create a lifting movement, so a lifting output or a forwards and backwards or up and down movement.

Now, Alex asked an interesting question here, "Can you move more than one part of the toy?" What do you think? Pause the video, just have a little think about that.

Okay, quick check for understanding again then.

Which type of movement is not made by the two simple pneumatic systems that we have looked at? Is it A: forwards/backwards, B: up/down, or C: circular rotation? Pause the video here, just have a think about that.

And the correct answer, it was C: circular rotation.

So that is the type of movement that is not made by the two simple pneumatic systems that we have looked at.

But the ones that are are forwards/backwards and up/down.

Well done if you got that right.

Now, we can use a three-way connector to make one input direct air to two different points, our outputs, so we can have the toy moving in some different ways.

So this is a three-way connector.

So we have the input, but we have it v-ing off to two potential outputs.

So this is a Y connector.

You can also have a T connector.

It works in a very similar way, but you can see here we've got the one input coming in, but then we've got the two outputs going out in like that T shape.

Now, these are really nice and easy to remember because they just look like what they are called.

So the Y connector is the shape of a letter Y, and our T connector is the shape of a letter T.

Now, Alex is explaining how a simple pneumatic system could open and close the jaw of his crocodile toy using lift.

"Now, the balloon could be inside the jaws of the crocodile." That's a great idea.

"So when I squeeze the bottle, the balloon will inflate making the jaw open." So he's got his input, which is his plastic bottle that he's going to squeeze, and then his output is the jaw of the crocodile lifting open, and that's being caused by this balloon inflating inside the jaw of the crocodile.

I love the idea from Alex.

Aisha is explaining another way to use it.

So in her idea, the plunger on the output syringe could have the tongue of a snake attached.

So when the plunger moves in and then out, the tongue will move.

We've got a great idea there and very different to Alex's, but really interesting.

Laura's got a different idea again.

So Laura has suggested the plunger on the output syringes could have the legs or claws of an animal attached to it.

Something like a crab or a lobster, maybe.

When the plunger moves in and out, they will move too.

And hopefully you can see that in the diagram.

All great ideas.

These pupils have had their own ideas.

So Jacob has said, "I could use a Y connector to make two eyes move up and down on a crab's head." And Andeep has suggested, "I wonder if I could use the balloon lift to make water come out of a whale's back." Very cool idea.

Okay, quick check for understanding on that then.

Which of these is used to split the path of the air into two different outputs? Is it A, B, or C? Okay, pause the video here to have a go at this.

How did you get on? The correct answer was A, it's that Y connector.

Well done if you got that right.

Okay, it's gonna be over to you again now then.

I'd like you to think about three pneumatic systems that we have looked at today.

That's the bottle and balloon, the single output syringe and the double output syringe using that connector, either the Y connector or a T connector.

And I'd like you to think about these questions.

How can they be used to make a moving animal toy? And which part of the animal could you get to move? I'd like you to discuss your ideas with your partner or your group.

Pause the video here to have a go at these tasks and good luck.

Okay, now these pupils have discussed their ideas with each other.

So Jacob here has said, "I could use a Y connector to make the eyes move up and down on a crabs head." Andeep has said, "Good idea.

If I made a crab, I could use the same system with a Y connector to make the claws move in and out." So by sharing their ideas, they've actually come up with better ideas, and that's a really great thing to do when working as part of a design team.

How did you get on discussing your ideas with your group or your partner? Hopefully you've come up some really lovely creative ideas for a toy using those pneumatic systems. Okay, so let's summarise today's lesson.

Today we've been looking at pneumatic systems, and these are our key points from today's lesson.

Balloons and plastic bottles can be linked to make a pneumatic system.

Also, syringes and plastic tubing can be linked to make a pneumatic system.

Different pneumatic systems can create different movements.

And different pneumatic systems can create moving animals.

Well done for all of your hard work today and all of your creative ideas.

Thank you so much for joining me, and I will see you soon.