Glenn

Candles and lanterns have brightened the night for thousands of years in many cultures around the world.

Hi, I'm Glenn. Thanks for joining me as we run through an example of the engineering design process in action. In this STEM project, I'll design and prototype a lantern that uses electronic lighting, not a candle.

My second aim is to build a project that in some way has the look of a traditional shoji-style lantern, but with my own modern twist on how it looks. I am inspired by the beautiful timber work in traditional architecture, as well as the shoji screens – the timber frames covered in rice paper.

At first, I'm not sure how to get started. I've never designed a lantern before. You may feel the same way at the start of your projects. I decided to follow the steps shown here.

[Image on screen: Engineering Design Process with the stages in a circle.

1. Define
2. Identify
3. Brainstorm
4. Design
5. Prototype
6. Evaluate
7. Iterate
8. Communicate]

The Define step.

Before we can design a lantern, we need to figure out what makes a good lantern.

Let's start with the overall shape and the look of the lantern. I'll search online for traditional shoji-style lanterns. I'll sketch what I find. [Image onscreen of a sketched lantern.] Now we can see the essential parts that make up a lantern. A new project doesn't feel so overwhelming when it's broken down into smaller parts.

[Image onscreen: a mindmap with a sketch of the lantern in the middle and lines branching to different words to define the elements, for example one line goes to ‘frame’ which branches to ‘strength’, ‘joining’, and ‘removable’.]

Here I'm sketching a mind map. The project is the lantern, and the surrounding branches show what I think are the most important elements of my design.

The frame is the structure that all parts will likely be attached to. The lantern frame gives strength and holds its shape even under load.

Joining the timber frames together is definitely another area for me to investigate. For example, how will I cut the timber, and which glue or adhesive might be best. I'm also thinking that if the thin paper covering gets damaged, it might be useful if the panels could be easily removed for repair. I'm not sure how I'll do that yet, but that's okay. At this stage, we're just defining the parts that will need problem solving later.

The next branch I'll call infill. It will be inspired by the traditional shoji screen. Let's think about what we want the infill to do. One important function is to support the thin covering, traditionally a rice paper. Whatever material we choose for the infill, it will need to be joined. If I use timber, I'll need to research different timber joints. The infill could also help decorate the lantern and add visual appeal.

Real candles are a fire hazard, so let's explore electronic lighting, and it's a great way to build some STEM skills. If you turn the power off and on using a switch, then you are the controller. On the other hand, you could use a microcontroller or computer, which will follow a set of instructions on when to switch it off and on.

If you decide to make a simple circuit using an LED, you'll probably need to select the right resistor, so that the correct amount of electrical energy flows through the LED. That's where Ohm's law, a mathematical formula, comes in handy. We'll also need a source of electrical power, and there are several options to choose from – battery packs or cords with built-in switches that could connect to a computer's USB port. Between 3 and 5 volts is fairly typical. Voltage is the unit used to measure electrical pressure.

Now let's think about the covering. What does it need to do well? To make a bright lantern, the cover should be as see-through or transparent as possible. I'd like mine to give a soft, even glow – a diffused light. Even the thinnest paper covering when glued to a frame will add surprising rigidity. I'll need to check which types of glue, however, work best.

This next consideration doesn't affect the lantern's function. It's more of an aesthetic choice – how I want it to look.

Next, let's identify or name any constraints on our project. Maybe materials that are available, or budget, or a given time frame – deadlines. Limitations can have a big effect on our project.

For example, if I was limited to basic hand tools and common materials, such as these, [Image onscreen shows items such as string, straws, paper cups, elastic bands and wooden craft sticks.] then my project could look something like using cardboard and bamboo sticks [Onscreen: a basic lantern with square cardboard base and top held by 4 bamboo sticks with paper wrapped around the sticks]. If I had access to some timber and workshop machinery, my design could look very different [Onscreen: a square wooden base and top held up by 4 lengths of wood and framed paper infills].

Using advanced manufacturing tools, such as a laser cutter, CAD drawing, or 3D printer, could give a design that looks like this one [Onscreen: finished lanterns with patterned infills].

How would you measure the success of your final lantern build? What tests could we run? We could list some criteria that use measurable data. For example, the prototype must stay within a given budget. Or another criteria: more than 50% of people should find the design visually appealing. Or maybe the light intensity is a certain measurement.

Here's a light meter. [Onscreen: a light meter showing 892.9LX and 20.5°C] Can you name the unit used to measure light intensity? Well done if you can.

Some designers like to write a design brief. That sums up the key information for their project. Writing down a design brief can help keep in mind those important aims and the key criteria for success.

In this video you've seen that defining the important areas or parts of a project is a great place to begin. We've identified constraints. Also, success criteria, or how you'll measure success.

Remember, there's no one right answer. You get to define and identify what you think is important for your project. Sometimes it's only clear after you've made a start. So just start. Have fun.

I'll catch you in the next video. Bye for now.

[NSW Government logo.]

[End of transcript]

Glenn

Hi! Welcome!

In this video, you'll see an example of how brainstorming could look. The project is a lantern design. Earlier, I decided to use a traditional style lantern as my inspiration.

First, let's break the project down into separate parts. Then, we can brainstorm each part and sketch possible ideas.

[Speaker holds parts of an partially constructed lantern to demonstrate the following concepts.]

Parts of the project could be the frame for strength, infill, what we build inside the frames, the covering over the frame, and an electrical lighting solution.

Another possible area could be brainstorming shapes for a cap or a base. Here are the four parts [frame, infill, lighting, covering].

Let's brainstorm ideas for the frame. Remember, the frame must be strong, but also hold a translucent or see-through covering.

I'm sketching the front view of a container and where I could cut it in half. The part I'm using, I'm now sketching in isometric view. The cardboard used on the outside looks like a frame, but really the shell structure of the container gives the strength.

Here's a front and side view of a cardboard container and an isometric sketch. Cutting away the sides will form a frame, but I'll need to access the inside for the light.

Now I'm exploring the classic look of a timber material. Thinking here in 3D of how a frame could be arranged. My idea here is to use bamboo sticks. Sometimes brainstorming is helped by manipulating your materials to spark ideas and certainly to help visualise and sketch them.

This wooden frame uses Popsicle sticks with an experimental covering of baking paper.

[Speaker sketches the different views of a piece of the lantern frame.]

Here's how it appears in side view [text overlay reads 'Orthographic side view'] and the front view with covering [text overlay reads 'Orthographic front view']. Here's an isometric view.

If your inspiration is a modern aesthetic, make a list of the modern materials surrounding you. A colourful construction set is one idea.

[Visual depicts a frame made of a construction set as the speaker sketches. Text overlay reads 'Orthogonal side and front view.]

During brainstorming, have fun finding some out there alternatives. In other words, options that are not obvious or common. This construction set may not be my first choice, however, it may help to leapfrog to the next idea.

Here's an isometric sketch showing just how easy it would be to snap together these components.

This frame is made using coffee stirring sticks. [The visual depicts a rectangle frame of sticks with two cross beams for support.]

Here I'm sketching the front and left hand side view as well as an isometric view. These small and quick sketches are sometimes called thumbnails.

Here I'm brainstorming ideas on how to fit the frames together. They could assemble like that, [two pieces of frame flush against each other with corners aligning] or maybe I could have the corners touching. That would be hard to glue together, so maybe what I need is an outer frame that the frames fit inside, and the same idea using some craft materials.

Moving on to infill, ideas could include painted directly onto the covering, made on a 3D printer or woven from air-drying clay.

The design for the infill could be more traditional or creative. Do this by sketching loads of thumbnails. A traditional way of allowing timber infill to cross over is by cutting halving joints.

Next part covering the frames. You could brainstorm a list of materials that could include tissue paper from a gift box, fabric from a shirt, baking paper, a traditional rice paper that has a texture or pattern, or even some tracing paper. How will you then attach your material to your frame? Will you consider staples, sewing, an adhesive tape, or even a traditional rice glue?

And now the lighting part. Your brainstorming could include, for example, a three volt battery and LED, a plugin USB, a torch, a microcontroller with a strip of LED lights that automatically turn on when it's dark or change colour dependent on temperature. Packs of LED candles are a cheap option.

To visualize the whole lanterns some guidelines may help. Here I'm drawing isometric guidelines by tracing around a template.

And here are three possible shapes for the cap. This cap uses layers of curved cardboard. This cap is based on a pyramid. This one is a sculptural freeform idea.

Thank you for joining in. I hope you have a lot of fun brainstorming ideas for your project.

[End of transcript]

Glenn

Hi, thanks for joining in. This video shows an example of drawing and planning our design for a lantern.

I'm sketching the lantern design.

[Video shows a hand drawing the lantern design as it's described.]

I'm using some isometric guidelines to help. Beginning with a piece of timber on the top and the base. These lines will be the bamboo sticks that hold the top and the base together.

Underneath each of those I will extend the little leg, so they go through a hole in the base. Adding some very light wood grain. And now the outside of the screen.

Inside you can draw whatever your design is. I'll use a basic cross. Notice from each of the corners I'm drawing a very short line in the same direction.

Imagine if I was redrawing those two lines, but start them at the end of the short line. So slide them across and redraw. I'm using the same treatment in four places. [Drawing creates a 3D effect for the cross.]

On a piece of paper or a ruler, make a mark that's a little longer than the top of the lantern. Watch as I draw the screen on this side exploded or detached away from the lantern. [Draws the 3D style screen design separated from the lantern drawing.]

There's the outside of the screen and my infill. And you'll notice these short lines are still isometric but in the opposite direction from the one we did previously. And don't forget the outside of the screen, the depth.

Great.

I'm sketching some light lines just to make it really clear how or where that attaches.

I'm sketching just a hint of my lighting solution. In my case it's an LED array. And I'm hoping to use a microcontroller that I plan to attach underneath.

I'll need something on top so that I can pick up the lantern. Here's a sneak peek at how that could look as a prototype. [Video shows a wooden prototype.] Where we have the base and a skirt of bamboo sticks so that the screens don't fall out. Here's the screens and here's the frame.

Using this guideline I'm drawing a row of thin, what's called leader lines. [Draws a line from each part and numbers them.] And those leader lines will let me number all of the separate parts or components in my design. I could draw a separate table with the name and number of each part.

This is a view from the front. [Draws views from the front, side and top.] Even a quick freehand sketch will help us think about all of the parts and how they might fit together.

On the side view I'll make it a sectional or cutaway view, handy for showing things. For instance the stick goes through the base and only halfway through the cap.

This tab is really all I'll see when looking down, or the top view. Unless I add some hidden detail, these dashed lines show an edge that's hidden underneath, like the edge of the skirt.

If you'd like to see how to draw using an isometric template, check out the final video in this series.

Now we start planning in more detail. Here's a representation of the base. I'll need to plan the sizes to be able to make this.

[Video shows the various parts, the dimensions and how they will fit together.]

Why did I choose 90x12? I found that it was commonly available from my local hardware.

I need to plan now how far apart to drill the holes for the frame. Let's begin with the plain base. Remember we're adding a bamboo skirt to stop the screen falling out.

The bamboo sticks measure 4x4mm, so let's place those right on the edge. The coffee stirrer sticks are 5mm wide, and that's what the screens will be made from. Let's place the screens down onto the base.

Beside the screens, we will drill holes in the base, and that will allow the bamboo sticks, or the frame, to pass through.

Now let's zoom in a little closer and add some measurements, what's called dimensions.

The bamboo skirt is 4mm wide, the coffee stirrer sticks are 5mm wide, but we may also need a little gap. Let's say 1.5mm, that's important because with the paper glued on the back, or if they are a little bowed, we might need some extra clearance.

The distance from the centre of the hole to the edge of the bamboo will be 2mm, not 4. So in total, 12.5 from the edge of the base to the centre of the hole.

So the width of our base is 90mm, and we just calculated that it will be 12.5 on each side, from the edge of the base to the centre of the holes.

Can you find the distance shown here? The answer is 65mm.

Here I am looking straight down onto the base, I need to find the centre. If I draw two diagonal lines, they intersect exactly in the centre. Next I could draw a circle with a compass, and that would give me the centre of all four holes.

Remember you calculated the distance between the holes to be 65mm. What we actually need now is the radius so that we can draw the circle.

Here's a right angle triangle, we can use Pythagoras. Here we have the hypotenuse, we need to find R. Grab a calculator and check my math. Do you agree with this radius?

[Onscreen: mathmatical calulations with the result r ≈ 46mm.]

If so, that means the circle will be slightly bigger than the base, but that's OK. Let's round down to 45mm.

This important dimension, 65mm, is also how wide I plan to make the paper covered screens.

Previously we have looked at brainstorming for ideas. This is Crazy 8, another way for rapid ideation. [Folds a sheet of paper in half, half again, and half again to create 8 sections of equal size then draws a different design in each section.]

Now I have a chosen design for the screen, I'm going to draw it neatly and actual size, 1 to 1. The coffee stirrer sticks were 160, so I've trimmed one of those and used it to actually mark off that distance. 65mm wide.

These drawings will work as my guide when gluing together the timber screens. I'll protect them in plastic.

[Video shows how to create designs in Canva.]

Another option for drawing your screens may be a digital app, such as Canva, that you can see here. Select a few lines and then hit delete. Press L and a line appears. Problem is I have to adjust the thickness to be the same as the others. So probably easier to just select, click on a line and then make a duplicate.

Drag that across and then pick up one end. Left click and drag one end of the line, same thing for the other.

I'm using another copy here and dragging it into place. Now I can discard all of the other designs, so I'll drag a box around them and hit delete.

At this stage of the engineering design process, I'm thinking critically as well. What if I make the angle sticks slightly shorter and then rotate until I touch the side and glue them in place? It could mean that it's a lot easier and quicker to assemble.

Now back to the original design. I'm grouping all of these lines by selecting them and clicking on group. Now I just need to duplicate and slide the copy across. Hit the duplicate button again.

Now I can download this page as a PDF and print.

In terms of the screen and the shape of the infill, it's so much fun creating your own design.

In the next video we get to prototype or build an example of our design.

I'm Glenn, see you then. Cheers.

[NSW Government logo.]

[End of transcript]

Glenn

Students are proud of their Shoji-inspired lanterns.

[Video shows various finished lanterns.]

In this video, you'll see examples of prototyping, evaluating, iterating – in other words, improving your idea – and communicating a design.

Prototyping.

Let's begin with the base and the cap.

[Video shows the narrator performing the actions described.]

First, construct diagonal lines to find the centre. Use a compass to mark off where the holes in the base need to be drilled. For accuracy, tape the cap underneath the base. But remember, set a depth stop and drill only halfway through the cap.

Ordinary drill bits are difficult to drill exactly on centre. If possible, use a specialised woodworking drill bit, such as this, that has a sharp central spike. And remember we're drilling all the way through the base, but only halfway through the cap.

Here I'm marking the bamboo sticks to length. I'm trimming them with pliers, sanding the end square, and then gluing down to the base. When the glue squeezes out, make sure you clean that up, either with a stick or a damp cloth.

And it's really important to make sure that's aligned, otherwise you won't have room for the screens to fit in. On a future version, or iteration, I could leave even more space, just in case the holes weren't drilled exactly on centre.

I'm gluing in a slightly shorter piece on the left, and its mirror image on the right. Keep checking the bamboo is neatly lined up with the edge.

I'm leaving a 10mm gap on both the base and the cap, so that once it's all assembled, I'll still be able to slide one screen in and out.

I'm using coffee stirrer sticks to make the screens and infill. I'll lay the sticks over my design, and hold in place with tape. Hopefully the PVA glue won't stick to the plastic pocket.

Let's conduct a test on two different pockets, and see how easily the dried glue blobs can be removed. [Video shows 2 different types of pocket.] Pocket A performs better. This is an example of how evaluations can be useful during the design and engineering process, not just for the final evaluation.

For these side pieces, I've cut and sanded to length a whole bunch all at once. For the top and bottom, I've simply cut one of the stirrer sticks in half. You'll see in a moment why the exact length of the top and bottom isn't important.

With some PVA glue on hand, I'm going to first tape the top and bottom into position. So remember they're a little longer than we need. We'll trim those later.

Now with some PVA glue on both ends, pop the side in and secure with tape.

Here I'm carefully marking off the length I'll need for the infill pieces. I'm gluing and then taping them into place.

If the corners are made as right angles, then all of the screens will be identical, which makes construction of your project so much easier.

I wondered if there was a better method of holding the parts in place. Here I'm experimenting with wooden blocks. The problem was they were so easily bumped out of place.

These corner blocks worked really well, but were difficult to make and often broke. I tried the idea of using clips to hold the corners, but it was too much force to hold the clips open this wide.

This thin strip of metal was much easier to clip to. Unfortunately it was soft and ductile and could bend out of shape.

This version, or iteration, uses a 3D printed right angle. This polymer material was thin enough to be easy to use, but also strong enough to hold its shape. This jig or template makes it much simpler to assemble lots of identical screens.

Here the excess at the corners is being trimmed using pliers. A parallelogram is easy to push out of shape or deform. Adding a triangle will prevent this, whether small or large.

This is how to gently sand the screens flat.

Let's try using a common tissue paper for covering this screen. Here I'm using a sponge to dab PVA glue all around the screen. Make sure the screen is flat to the paper by adding a mass, or weight.

Cut the screens out with scissors and then very carefully trim right to the timber.

When the glue is absolutely dry, you can apply a very light mist of water, which will shrink and tighten the paper covering on the screen.

These screens were made by students using different paper and infill designs.

Here the work boards are being stacked away.

In this stage we're assembling the frame. Ensure that these two openings are opposite each other, and apply glue to the cap only, because we'll be putting these bamboo sticks through the base, but glued into the cap.

Once that's dry the concept is the base slides up to capture and hold the screens.

Not everything goes to plan. The final screen slid over, but did not sit outside the frame. And then this happened.

[The screen falls through the inside.]

How could we stop the screen from falling in? Maybe glue an object behind it, perhaps use blue tack, or use some of the materials that we already have.

The plastic tubing prevents the base from falling downwards, because then the screens would fall out. An even easier solution was to use elastic bands.

Next comes prototyping the electronics. Find a way to hold the LED matrix securely. Insert the hookup wires as shown here, and then carefully solder the three joints.

For this iteration or version, the LEDs are about the height of a candle. I've also drilled a hole in the base, so that the wires can connect to the controller.

Here I'm stripping the insulator from all three wires. Place the wires into the ring connectors on the controller.

Trim a small piece of tubing from silicon or PVC. And then wedge that into the ring connector. It makes a pretty decent connection. So do the same thing in three places as shown.

Next we'll prototype some code. Can we make the LED appear as a flickering candle? I'm using the MakeCode environment because it's so simple.

In fact this forever loop really is just the one instruction repeated four times, but I've played around with the pause time, or the hue, or even the luminosity. Experiment, change one thing at a time and see what effect it has.

This effect is from changing the hue from around 40 to 100. My next iteration of code could use this "pick random" number to give an even more realistic flicker to the light.

Communication

I'm using an isometric template to help draw a pictorial view. Drawing a picture of your design is using an international language that's easily understood by lots of people, especially non-technical people.

The idea with these drawings is not creating artistic work, it's to show technical intent, or in other words what you're trying to achieve, using shape, the arrangement of parts, and details.

During the design and engineering process a combination of drawings will be used: pictorial drawings and orthogonal drawings, rough thumbnail drawings, right through to professional looking CAD drawings.

With some regular practice you'll be amazed at how quickly your drawing ability grows.

In the next video we'll be prototyping a lantern made using a 3D printer and a laser cutter.

I'm Glenn, thanks so much for joining in on the video, see you next time.

[NSW Government logo.]

[End of transcript]

Glenn

Welcome to video 5 of the lantern project.

[Image onscreen: 3 finished lanterns]

The lanterns on the left and right are handmade, but all provide light and will need a removable screen. In this video we'll take a different direction and create a lantern using CAD, Computer Aided Design.

[Video shows the narrator performing the actions described.]

First we'll be computer modelling the base and cap and manufacturing using a 3D printer. Next we'll create the laser cut screens and assemble them onto the base.

The base I've drawn is a fairly simple object. It will need a groove for the screens to fit in, and underneath where the microcontroller goes, I've put a little cut out for the lead to attach.

I made a mistake here – I didn't realise until too late that the lead needed to come into the controller from this side. A future iteration should have the opening here and a hole for the wires to pass through.

A boss is a round projection that will hold the microcontroller out away from the base, and on the end is a spigot that fits exactly inside the holes of my controller. I searched online and found the exact diameter of the ring connectors. I made holes in the bosses so that I could wind in these screws and that holds the microcontroller in place.

How would I know how wide to draw these trenches for the screens? Easy, do some research. Online I found this plywood is supplied in exactly 3mm thickness.

On the cap piece is a handle and a circle beside the screen that lifts out. Underneath I've also got a trench, but at the front is an extra deep trench and that's so that the front screen can lift up and out.

Here I've printed the 3D parts so that I can mount the LEDs onto the base. I've used a 4x4 matrix.

I'm placing the negative lead, the black one, through the ring connector on the ground. And then I'm mounting it onto the spigot on the boss. Attach a screw to complete the connection.

I'm using side cutters to snip off some silicone tubing and I'm using that to wedge in the positive lead into the ring connector.

There's no boss underneath. However the port zero does have a boss so I'm sliding that through and attaching with a screw.

Here's the lead that's going to power up the microcontroller as well as the LED matrix.

Now it's time to make the four laser cut screens. Because the screens are flat we'll only need to use a 2D drawing software such as Inkscape or something similar.

Use a rectangle tool to draw a rectangle roughly to size. I'm clicking and dragging the height of my rectangle to 160, but it's going to be a lot more accurate to click in that field and type 160 millimetres. I'm dragging the width but again let's click and type let's say 65 millimetres.

Most laser cutters will cut only the lines that are red, pure red. So I found the RGB sliders and I'm pushing the red all the way up and the others down.

I'm drawing a guideline inside my rectangle and I'm going to make sure that I don't go outside that guideline. And now I'll find the pen tool, the old-fashioned pen looking one, click on that.

And as an example I'm creating a shape here so this is what's going to be cut out. The shape will need to be completely enclosed and I know it is. When I reach the end and I get a little blue highlight box that tells me that it's a completely enclosed shape.

When you've completed your design then cut and paste four of them across your page.

Can you help me do this calculation? If I have four screens across the page, each with a five millimetre gap in between, how wide will my plywood board need to be to fit the four screens?

When you've finished making your CAD drawing, you'll need to save your drawing and then export it. I'm exporting mine as a PDF, but you may need a JPEG or something different. You need to check what your laser cutter requires.

Load the cutting file onto the laser cutter and cut out your screens.

I'm using a brush to apply glue onto the screen. Compared to the stirrer sticks, I have so much more surface area that should give me a really good bond.

Here's the traditional rice paper. I'm gluing on just three screens, leaving one detachable. And at the other end, I've glued on the cap as well.

Coding.

The code is the instructions the microcontroller will follow. This software platform uses a convenient drag and drop method of coding. Although I can click here to see it written as Python code.

This LED matrix has special code found under extensions, Neopixel. Download the library of coding options that suits your LEDs.

This line of code is for setting up. It will go into the on start section and designates pin zero as where the yellow data wire leaves the microcontroller. And this we change to match the number of LEDs in our matrix – 4 times 4, 16.

This line of code is dragged into the forever loop and switches the LED on. This extension allows us to control more finely the LED colour.

Under the tab called Basic is the pause commands. I've selected the 100 milliseconds. Do you know how many milliseconds make up one whole second? Watch as I select the one second pause and it converts it into milliseconds. So the answer was a thousand. Well done if you got it.

For any lines of code, right click to duplicate. I'm recreating those two lines because I'm going to change the settings and I want this one to be the flicker in the candle where the luminosity is reduced slightly and the pause is just for one tenth of a second, 100 milliseconds.

So we've got a long and a short flicker. And I'm going to repeat both of those instructions again, but with slightly different settings. These lines of code keep repeating in an endless loop.

It's a very simple program and a great way to get started. Research online how to code a flickering candle flame. The random number command makes the lantern look a lot more realistic.

This is the final video in the series. So thank you so much for joining in. I've really enjoyed this project. Keep practicing your incredible STEM skills.

I'm Glenn, see you next time.

[NSW Government logo.]

[End of transcript]