Lesson video

Hello, thank you for joining me for your design and technology lesson.

My name is Mrs. Conway, and I'll be guiding you through your learning today.

So today's lesson outcome is, I can test and evaluate the manufactured prototype.

So we're looking at those final tests and evaluations that we need to do on our prototype.

And our keywords for today are evaluation, design specification, destructive testing, non-destructive testing and modifications.

We'll go through each one of these in detail as we work through the lesson.

So the first thing we're gonna look at is evaluation against the design specification.

And once a prototype is complete, the product needs to be tested and evaluated.

To evaluate something, it's just to check how good something is and also consider how to make it better.

No product is ever perfect, and further modifications can always be considered.

Now, one way to evaluate a prototype is to evaluate it against the original design specification that you as the designer wrote.

Designers evaluate against the design specification just to make sure that the final product meets the required standards, the functions as intended and satisfies users' needs.

But it also supports continuous improvement and iteration as it helps to provide insight for refining and modifying future designs as well.

So it's a really important stage.

Let's just do a quick check for understanding on that.

What can we evaluate a final prototype against? A, existing product.

B, design specification.

Or C initial design ideas? Pause the video here just to take a moment to think about your answer.

How did you get on? The correct answer is that design specification.

So we can evaluate our prototype against the original design specification that we as the designer wrote.

Now, the design specification just to remind you, describes what a design must have or do and is dictated by the research that has been gathered prior to it.

It is written really early on in the designs process after the research, but before things such as prototyping, just to make sure and ensure that the product meets the user's needs.

Now Laura worked on the design opportunity of making herbs accessible to wheelchair users.

Now this is Laura's design specification.

This was broken down into subheadings such as user, materials, function, and this is just part of a design specification, not the full thing.

She then had her specification points in the next column, and the last column was her justification, and the justification was her explaining and referring directly to the research to explain why she made the decision she did in her specification points.

Now, feel free to pause the video here if you would like to look at this in a little bit more detail.

This is the rest of her design specification.

Again, feel free to pause the video here if you would like to look at it in a little bit more detail.

So let's just do a quick check for understanding on design specifications then.

What is the purpose of a design specification? Is it A, it provides step-by-step instructions for making the design.

B, it describes what a design must have or do.

Or C, it lists personal opinions about the design.

Feel free to pause the video here if you would like to take a moment just to think about your answer.

And the correct answer, it was B.

So the purpose of design specification is to describe what a design must have or do, and it's usually led by the research that's been carried out rather than any personal opinion from the designer.

Now, Laura has evaluated her prototype against that original design specification of hers that I just showed you.

And she's done this by deciding whether she has either met the specification points or not met the specification points.

And she's pulled together this table just to help her do that.

So you can see here she's repeated the subheadings in that first column and the specification points in the second column.

But instead of the justification points she had previously, she's now got a third comment, which simply says, met or not met.

She can then take each one of these in turns and simply either do a tick or a cross to explain whether she has met it or not met it.

You can see here she said that she has met the herb growing system must be suitable for wheelchair users, but in her thoughts, the materials must be waterproof and suitable for cleaning.

She has not met that specific point.

Now she then goes on to actually explain why she thinks she has met or not met each point, and this is forming part of her evaluation.

She does need to explain this a little bit more.

So where she has said that she has not met or met it, she's just gone on to give a little bit more information.

So here the herb growing system must be suitable for wheelchair users.

She's gone on to explain that the product goes on the countertop, so it's more accessible from a wheelchair than a window sill.

She said she had met that point.

So she's just explained why.

The next point the materials must be waterproof and suitable for cleaning.

She said she had not met to that point, and again, in her explanation, she just explains why she feels she's not met that.

The polymer sheet I used on each top step didn't protect the card below well enough.

So she's just explained it that little bit more.

Here are further examples of Laura evaluating against the design specification.

Right, it's gonna be over to you then to have a go at this.

Your task is to evaluate your final prototype against your original design specification.

And you could lay it out in a similar style to the table below, which is similar to what Laura did.

If you'd like to do that in a different way, that's absolutely fine, but just one way to do it is this table kind of layout.

Okay, pause the video here to have a go at this task and good luck.

Right how did you get on with that? So yours is gonna be slightly different, but this is an example of what could have been included, and this was Laura's example.

So this is a completed evaluation against the design specification.

Again, you can see her specification points.

She then decided whether she has met or not met it, and she goes on to justify that by just explaining how she feels she's met or not met it.

Again, if you would like to go through that in a little bit more detail, feel free to pause the video and you can read that through.

Okay, compare yours to Laura's then, and just see and make sure that you've put in enough detail, especially into that justification, whether you've met or not met better.

Again, try not to just do this on a personal opinion.

Try and do it factually on the evidence that you can actually see in front of you with your product.

Okay, next we're gonna look at testing, which is a different part of the evaluation process.

So testing is another way to evaluate a final prototype, and there are two main types of testing.

You have destructive testing.

Now, destructive testing is testing that destroys the material or the product.

Kind of says it in the name.

Non-destructive testing, shockingly, that's testing that does not destroy the material or the product.

And destructive testing would be better suited during the design, development and research stage of the design process.

Whereas non-destructive testing is better suited for the end evaluation as it just makes sure that that prototype is not gonna get ruined at that very last stage, which is something you want to really avoid.

So non-destructive testing is the best for this evaluation of the final prototype.

Okay, let's just do a quick check for understanding on that.

What type of testing does not destroy the material or the product? Is it A, destructive testing.

B, procedural testing.

C, non-destructive testing.

Or D, declarative testing? Feel free to pause the video here just to take a moment to think about your answer.

And the correct answer was C, non-destructive testing.

Well done if you got that right.

So the designer must first decide what it is they actually need to test on their product.

And Laura here has decided that she really needs to test that the storage hole in the centre of the her planter can actually fit all of the necessary tools for potting and harvesting at the herbs.

Now, once she's decided on what it is that she needs to test, she can then devise a way to carry out those tests.

Now, Laura may need to test other things.

We're just gonna use this sort of as an planter example for now.

Now, Laura's decided to test her storage department in two different ways.

The first one is collecting the necessary tools and placing them inside the compartment to ensure they fit and do not cause any damage to the product when being removed and replaced.

She's also going to observe her user using the product to see how they find the storage compartment as well.

So she's decided on what it is that she wants to test, and she's now decided on the method in which she's going to test that.

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

The first thing I'd like you to do is just to consider what testing you need or want to do for your final prototype.

What is it that you need to find out specifically for your product? Now, that might be slightly different to the person next to you, but feel free to chat through your ideas.

Secondly, then I'd like you then to explain how you will actually carry out each of these tests.

So just like Laura did, she decided she wanted to check the storage hole compartment in her product, and she decided on two different ways of which you could actually test the use of that.

Okay, pause the video here to have a go at this task.

All right, how did you get on? So the first thing I asked you to do was to consider what testing you'll do on your final prototype.

Now your answer will be slightly different to Laura, but just compare your answer to hers.

So she's explained here, "I need to test the strength of my herb planter to check it can hold six potted herbs as planned.

I also need to check how accessible it is for my wheelchair user." So these different tests that Laura needs to consider.

So that is her deciding on what she actually needs to test.

Your second task was to explain how you will carry out each of these tests.

So again, Laura goes on to then decide this.

"I will get six potted herb plants to put onto the herb planter to check that they hold their weight, fit, and can still be harvested easily.

So to harvest is to pick off the herbs.

I will also observe my wheelchair user watering and harvesting the plants to ensure that it's accessible and easy to use." So she's decided on two different tests to test those two different areas.

Just compare your answer to Laura's and just consider, are your tests thorough enough? Have they got all the detail that they need to be able to find out what you need to find out about your prototype? Okay, last section then.

We are now gonna look at future modifications.

So we've done our evaluation against our design specification and our testing, and hopefully that will help us give an idea of what future modifications we need to do.

Now, future modifications are when the designer makes changes or adjustments to improve or to alter a product.

The evaluation against the design specification and the testing are then used to inform and also justify any future modifications to the product.

A justification is that reason or explanation for why something is done or believed to be right.

Designers just need to ensure that any future modifications are justified based on the client's wants and needs rather than all of a sudden just going off on a complete tangent.

Okay, let's just do a quick check for understanding on that.

Why is it important for designers to justify future modifications to their products? Is it A, to make random modifications that the designer prefers.

B, to ensure that changes align with the evaluation and testing results.

Or C, to avoid considering the research and testing done throughout the design process.

Feel free to pause the video here just to take a moment to think about this.

Okay, and the correct answer was B.

So it's really important for designers to justify future modifications to their products just to make sure that those changes align with the evaluation and the testing results rather than just suddenly coming from nowhere with these ideas.

Now, Laura's evaluation against the design specification gave her some points that could be used for future modifications to her product.

Now, just to remind you, these were, the product is still not as waterproof as it needs to be protected from watering of the plants.

And also the storage compartment could be a little bigger to store slightly larger tools or also more of them.

So those were her two points that she got from her design specification.

And she now needs to consider the ways to improve her product using these points from her evaluation and also her testing.

Now, she could present these ideas as any of the following or even just a combination of them.

So she might decide to just explain what future modifications she would do for this product.

Or she could do some sketch drawing of those modifications.

It's also the option to do some CAD drawing of those modifications as well.

Or if she'd prefer, she could do a model or some sort of model of the prototype with those modifications altered.

It's completely and utterly up to her what she does.

She might do a range of those.

So she might do several of them or just one of them, or even all of them if she really wanted to.

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

Your test then is I'd like you to write your own success criteria for evaluating, testing, justifying and carrying out future modifications on your product.

The second thing I'd like you to do is then use that success criteria again for evaluating, testing, justifying and carrying out future modifications on your product.

Feel free to just think about what we've just gone through and the process that Laura went through when she was evaluating against the design specification and also when she was testing.

Okay, pause the video here to have a go at this task and good luck.

Right, how did you get on with this? So I asked you to write your own success criteria for the evaluating testing and justifying and carrying out future modifications on your product.

So compare your answer to mine and just think about have you missed any part of this process? So the first thing then, evaluate final prototype against the design specification to say whether you have either met or not met the points.

Then it's that justification stage, so to explain how they've been met or not met.

So just give a little bit of reasoning into it.

The next thing then was decide on what needs to be tested.

Once you decided what needs to be tested, you then need to decide on how to carry out those tests.

And then you can use testing and also the evaluation against the design specification results to pick out what could be improved, what could be made better.

And then using the ideas of what could be made better.

You can then present future modifications in whatever way you would feel best.

It's completely utterly up to you.

Now, as I said, your success criteria might be slightly different to mine, but just compare it to mine.

Have you missed anything out? You might have extras put into there as well.

Your second task was to then use that success criteria to help you evaluate, test, justify, and carry out those feature modifications on your product.

So hopefully as you've gone through each of your points, you can do that as a success criteria to tick off as you've completed each one.

That will hopefully result in a really strong load of ideas for the future modifications of how your product could be taken forward in the future.

Okay, so let's just summarise today's lesson.

We've been looking at testing and modifications.

Now, once a prototype is complete, the product needs to be tested and also evaluated.

Now to evaluate, it's just to check how good something is, but also more importantly, to consider how to make it better.

And designers evaluate against the design specification just to ensure that the final product meets the required standards, as functions as intended, and also satisfies the user's needs.

That design specification was written for a reason and for a purpose based on the research.

So we should be comparing against that.

Now testing can also be used as a way to evaluate a final product as well.

And the evaluation against the design specification and the testing combined are then used to inform and justify any future modifications to the product.

Well done for all of your hard work today.

Hopefully you've got some really good ideas for those future modifications of how your product can be taken forward in the future.

Thank you for joining me for the lesson, and I will see you soon.