Lesson video

Hello there.

My name's Mrs. Taylor, and I'm really pleased you can be here to join me for our lesson today.

Our lesson today is foam modelling techniques, and this is part of the Ergonomic Design Accessible Controllers unit.

The outcome, I can use foam modelling to develop ideas.

There are three key words, prototype, which is a simple low-cost model made to check size, shape, and function.

Styrofoam, a lightweight foam used in modelling and iterate a process of refining and improving a design.

There are three parts to the lesson, prototyping, foam modelling, and iterating.

We are going to begin with prototyping.

Prototyping is making a rough version of your idea to see how it looks, works or feels before you manufacture the real thing.

Prototypes can be used to test ergonomics, appearance, weight, functionality, and even manufacturing processes.

Prototypes help test ideas early and help to improve designs.

We have a check for understanding now.

True or false? A prototype is the final end product.

Pause the video and have a go.

Wonderful.

Let's check.

That's right, it's false.

And the reason why? A prototype is a simple low-cost model made to check size, shape, and function.

Well done.

Creating a prototype has several benefits.

Prototype uses include to communicate ideas, which makes it easier to visualise than a sketch.

To identify mistakes, spot problems before production.

Savings, time and money isn't wasted on correcting errors on a finished product.

Iterate an opportunity to improve the design.

And test ideas, users can check if the idea works.

Prototypes can be made from lots of materials, but they are usually made from inexpensive and easy to use materials.

Here we have a table with five examples and justifications to explain why they are suitable.

Cardboard is lightweight, easy to cut and inexpensive.

Paper is good for drawing and also inexpensive.

Foam or clay is easy to shape and create 3D objects quickly.

Construction kits and building blocks are used to create small models quickly and then the blocks can be reused.

Recycled materials, these are free materials and come in a variety of shapes and sizes.

Here we have a check for understanding.

What are the benefits of making a prototype? Is it A, to test an idea? B, to find mistakes? C, to produce a final design? Or D, to speed up the manufacturing process? Pause the video and have a go.

Wonderful.

Let's check.

That's right.

It's both A and B.

To test an idea and to find mistakes.

Well done.

Before prototyping, producing quick annotated sketches will aid the process.

You can then use your sketches to select the most appropriate materials for prototyping.

Here we have an example of a page of annotated sketches.

You can see that some of the drawings are two dimensional and some are three dimensional.

Some also have arrows to indicate movement within the product.

We now move to task A.

Part one is to sketch a design for an ergonomic handheld joystick that meets the requirements on the right.

And part two is to annotate your sketch to justify how you met the design requirements.

The joystick design requirements are easily accessible buttons that can be used without causing finger strain, ergonomically friendly, providing comfortable support for the hand during extended use.

And can be fully operated with one hand.

Pause the video and have a go.

Wonderful.

Let's have a look at some of the answers you may have come up with.

Your design might look like this.

There is a move stick for thumb use with a larger top for better thumb support.

There are indents for the fingers to rest on.

Extra comfort, the design is curved to rest in the palm of the hand comfortably, and the jump or select button is in easy reach of the index finger.

Well done.

We now move to the second part of our lesson.

Foam modelling.

Styrofoam is a type of polystyrene that is stronger than the white polystyrene found in coffee cups and packaging inserts.

It is often blue but can come in a variety of colours including grey.

Styrofoam is easy to shape and has a smooth texture, making it ideal for modelling.

It's commonly used in design and engineering to create prototypes.

Here we can see a picture of a grey block of styrofoam.

We now have a check for understanding.

Why is foam modelling useful? Is it A, to quickly create 2D prototypes of products? B, to quickly create 3D prototypes of products? Or C, to quickly create final products? Pause the video and have a go.

Wonderful.

Let's check.

That's right, it's B.

To quickly create 3D prototypes of products.

Well done.

Marking out styrofoam.

The first thing you do is using your sketch, create a paper template for the plan, side and front of your prototype.

The second thing you do is to stick one of the templates to a piece of foam slightly bigger than the template.

Next, use the template as the marking out for cutting and shaping the foam.

Repeat the process for the other two sides using the templates.

Here we can see a paper template being added to a block of grey styrofoam.

Cutting styrofoam Using a coping saw, the first thing you do is clump the foam in the vice.

Remember not to tighten the vice too tight, otherwise you may damage the foam.

Number two, let the saw blade do the work.

There's no need to apply extra pressure.

Number three, keep an eye on your template as you cut.

And number four, make sure to cut within the waste area.

Your template should still be there when the cut is finished.

Here we have a picture of a coping saw.

Here we can see some grey foam with a template still attached held in the vice.

Another way of cutting styrofoam is to use a hot wire cutter.

A hot wire cutter has a thin metal wire that heats up when electricity flows through it.

This heated wire becomes very hot and melts through materials like styrofoam as you guide it along your cutting line.

The heat from the wire allows it to slice smoothly through the foam without creating much mess.

To cut using a hot wire cutter, the first thing you need to do is ensure that you are working in a well ventilated workshop.

Do not touch the hot wire.

Number two, with your foam laid flat on the bed, guide the hot wire through the material, following the template.

Move at a steady pace without forcing the material.

Allow the hot wire to melt through the foam, and once the cut is complete, remove the styrofoam from the cutter.

Once the foam has been cut, it can be shaped further with hand tools.

A hand file is a tool with a metal surface covered in teeth.

It's used to smooth or shape materials like wood, metal or plastic by rubbing it back and forth.

Hand files come in different sizes and profiles.

A surform is a tool with a metal blade with tiny holes or teeth.

It shaves off small amounts of materials such as wood or plastic to shape or smooth it.

Abrasive paper is used to smooth or clean surfaces.

It comes in different grades, sometimes known as grits, which tell you how rough or smooth it is.

The number corresponds to the size of the abrasive grit on the paper.

We can see here 50 grit is coarse, all the way through to 800 grit, which is extra fine.

Low number grades are rough and remove a lot of material quickly.

While medium grades are for smoothing things out.

High number grades are used for polishing sometimes as fine finishing.

Let's have a check for understanding.

Which grade of abrasive paper is the smoothest, and will give a fine finish? Pause video and have a go.

Wonderful.

Let's check.

That's right.

The answer is B, it's 400 grit.

Well done.

Finishing styrofoam using abrasive papers.

The first thing you do is use a smooth flat file to remove any imperfections on your shape.

And the second thing, start by using rough abrasive paper working your way through the grades to extra fine.

And next, rub over the styrofoam to get an even finish.

Here we have task B.

Part one, create a template for the design you created for Task A.

Part two, mark out the styrofoam and cut its rough shape using either a coping saw or hot wire cutter and part three, finish your styrofoam model by filing away any remaining waste and using abrasive papers for a smooth finish.

Don't forget to stay safe by following the health and safety instructions from your teacher.

Pause the video and have a go.

Wonderful.

Let's have a look at some of the answers you may have come up with.

Your model could look similar to this.

A template was used to mark the shape, which was then cut with a coping saw and smoothed with a hand file.

Working through different abrasive paper grades ensures a smooth finish ready for testing.

Well done.

We now move to the third part of our lesson, iterating.

Iterative design is a way of designing by repeating a cycle.

One, explore and investigate.

Two, create, design and prototype.

And three, gather feedback and evaluate.

This process is repeated, with each new version improving and becoming more suited to the user.

Iteration can also be used when testing a prototype.

Repeatedly testing and improving based on feedback.

Designers make quick prototypes, test them with users, and then use the results to make better versions.

Once satisfied, the final product is manufactured.

This ensures that the final product is the best version it can be.

Let's have a check for understanding.

Iteration is A, designing a product before it is manufactured? B, repeatedly testing a prototype and improving it based on feedback? C, a one-time test done after the product is finished? Or D, testing a product once before it is manufactured? Pause the video and have a go.

Fantastic.

Let's check.

That's right it's B, repeatedly testing a prototype and improving it based on feedback.

Well done.

We now move to task C.

Part one, using the phone model from Task B, conduct a series of tests to evaluate your prototype against the design requirements.

Part two, record your results in the table below and suggest improvements.

To remind you, the design requirements are easily accessible buttons, ergonomically friendly and can be fully operated with one hand.

Pause the video and have a go.

Wonderful.

Let's have a look at some of the answers you may have come up with.

For easily accessible buttons, the test may be time how long it takes users to press button A and then button B.

And your results could be this took longer than expected because of the position of the buttons in relation to where the fingers were resting.

The improvements could be: buttons could be placed inside the finger grooves for the index and middle fingers.

For the design requirement, ergonomically friendly.

The test could be to ask for feedback on how comfortable it feels in the hand.

And the results may have been those with smaller hands said this would be comfortable for them, but perhaps not for others.

So the improvements could be widen the circumference slightly to match the natural curvature of more average sized hands.

And the third design requirement can be fully operated with one hand.

To test this, you could observe how the user operates the joystick.

And the results left-handed users had the thumb indent on the wrong side.

Improvements could be to add a thumb indent on both sides.

And now we move to part three.

Using your test results, either sketch or model the next iteration of the improved joystick.

Pause the video and have a go.

Wonderful.

Let's have a look at some of the answers you may have come up with.

Your design may look like this.

This is a sketched example.

Buttons A and B have been moved onto the first and middle finger grooves.

The addition of more finger grooves.

The thumb indent is on both sides for left and right handers and the thicker circumference for average sized hands.

Well done.

We now move to a summary of our learning today.

A prototype is a simple first version of a product used to test and improve ideas before making the final version.

Styrofoam is a good material for modelling because it's easy to cut, shape, and use for testing designs.

Iteration is the process of refining and improving a design based on findings and feedback.

I'm really pleased you could be here to join me for this lesson today.

Thank you and well done.