Light Wall
The Exploratorium in San Francisco have a magnificent Tinkering Studio. It’s a space where educators, artists and engineers collaborate to produce beautiful, thought-provoking, and just plain fun activities and installation pieces.
One of their classics is Light Play, a wall of frosted screens back-lit with weird and wonderful shadows interacting with the light, with colour filter, and with the screens. It’s a tremendous activity, particularly good with younger children and family groups. One aspect we particularly like is the way it fosters a sense of collaboration and contemplation. If you’re working on the arrangement of materials behind the screen, you can’t really see what effect you’re having, since that’s only properly evident from in front of the screen. So you have to work with others, articulate what looks good, and work out how to get that effect again.
The Exploratorium have written up their approach on their own site and at Instructables.
Light Play workshops from the Exploratorium. Images © Exploratorium, used with permission. Thanks, tinkering.exploratorium.edu!
Our version
We loved the idea of Light Play, and our colleagues at the Centre for Life were keen to produce a set for use here in the North-East of England. But while the Exploratorium’s setup is wonderfully dramatic, for our purposes there were some challenges around component availability, ease of construction, and cost.
So we simplified the components considerably. The results aren’t as gorgeous, but they’re still pretty good. The activity has prompted the response and interactions we wanted, so we’re happy.
Here are a few more details about what we – Think Physics and the Centre for Life – built:
Boxes
There’s nothing clever about our boxes; they’re large cardboard boxes with big holes cut in each end. One end is covered (internally) with good-quality tracing paper to form a screen, the other is used for access.
Things we’d do differently next time
- Use smaller boxes. The ones we picked were 465 x 465 x 600mm, and are just a bit unwieldy in use and particularly in storage. I’d go 100mm smaller in each dimension.
- Cut the holes in the sides, not the end. Rectangular apertures are more interesting than square apertures.
- Using the sides of the boxes also means you don’t have the tape holding the boxes together encroaching on the display face of the wall. Oops.
- Absolutely use double-wall boxes. It’s tricky to cut, but the resulting boxes are tough enough to stand up to many uses – we’ve so far done two Maker Faires plus an art gallery installation and a bunch of school workshops. The boxes are looking scrappy, but they’ve at least one more busy weekend in them.
- Curved corners to the cut-outs are a pain to make, but absolutely worth it in the long run. They look more pleasing than square corners.
Lights
The Exploratorium’s lights use single-LED high-output devices, which are lovely but quite costly in the UK. They also require heatsinks.
Instead, we adopted triplets of extra-bright conventional LEDs. Having three individual light sources, even closely-spaced like this, isn’t ideal – they cast rather awkward shadows rather than the crisp outlines a single source would give, and they’re only just bright enough. However, the effect looks better than we’d feared, and the trade-off was worthwhile in our case. We used sets of three high-output LEDs of various colours, ranging from about 8,000 mCd output up to something like 11,500 mCd. Bear in mind that the sorts of cheap LEDs you’ll find in every electronics kit are rated at about 300 mCd. They’re also fairly cheap from suppliers like Kitronik and Hobbytronics.
We mounted the LEDs up on prototyping board, in series with a single current-limiting resistor to suit the specific LEDs, and powered them off 9V cells (so, ~3V each).
Things we’d do differently next time
- The gorillapod-style positionable necks were a pain to make. Literally. We bought cheap mini tripods from Amazon, un-popped all the segments, drilled them out, popped them back together, then threaded wires up the holes. There were blisters.
- In use, we rarely see people position the lights other than by laying the entire unit on its side. So:
- …next time, I’d just use a short length of dowel or plastic tube as an upright, and maybe mount the LEDs on a couple of segments of positionable leg.
- I’d be tempted to make only white light sources, and offer a range of lighting gels for colouring.
- Consider using small lamps like these from Ikea or these from Clas Ohlsen. On balance I’d probably prefer battery-operated lights, as they allow a finished box to be moved into a group wall display, but there’s a lot to be said for an off-the-shelf lighting solution too.
Fancy Lights
We made a small number of these ‘fancy’ lights. They use an Adafruit NeoPixel ‘Jewel’ array of RGB LEDs driven by a 5V Trinket microcontroller (like half an Arduino, and yes that’s a terrible description). Power comes from a single AAA cell via a step-up board which I still think must work via unicorns or something. I mean, how do you make 5V from 1.5V?! Mind-boggling.
When first booted, a small potentiometer controls LED colour. A second (button) input toggles the Trinket into a colour-cycling mode, with the potentiometer then controlling the rate of change of colour.
They can produce delightful effects… but the power drain is such that they last about half an hour, and hence aren’t terribly useful. Also: everybody wants one. Ultimately, we’ve withdrawn them from the workshop because they don’t add enough to make up for their limitations.
They’re still cute, though.
Turntables
To bring a little motion to the boxes, it’s worth having a few motorised components, like turntables. But they need to turn slowly, which is a challenge. Since I’ve never done the Exploratorium’s workshop personally I just assumed they’d made their own, but compiling this page I’ve realised they seem to be using jewellery display turntables, like these or this. Since I didn’t know that, I ended up reverse-engineering something which didn’t exist in the first place. Hmm. Well, I’m proud of our turntables. They turn slowly (about 1rpm) and despite looking pathetically fragile have proven quite robust in use. The old exhibit standby of ‘if it looks fragile, people treat it with care; if it looks solid, they’ll whack the heck out of it’ seems to apply. They do tend to fall apart in transit, but a minute’s ministrations with a glue gun solves that. The core is a geared 3–6V motor, driven off a single 1.5V cell. There’s enough torque to work reasonably well, and undervolting it slows it down even before you get to the gearing. The drive pulley is a short length of plastic tubing with a cardboard end-cap. A slot in the cardboard cap fits tightly on the motor shaft, then hot glue poured into the tubing fixes it well enough. Gaffer tape wrapped around the plastic tube provides enough friction for the edge drive to the turntable itself. Since we hand-cut the turntable discs they vary in diameter somewhat. The pivoted chopstick and elastic band tension spring keep the drive pulley and turntable in contact. The main turntable bearing is a short M10 bolt glued to the frame – ridiculous overkill, but it’s what we had lying around.
Things we’d do differently next time
Close-up of the drive system. Most of our units have an additional chopstick-segment guide stuck to the motor, which rides under the turntable platter and offers some extra support. I didn’t notice it had fallen off this one before taking the photo, because it worked perfectly well without it. Be aware that additional bodging may be required!
Turntables as far as the eye can see!
Effects, outcomes, and miscellaneous notes
This is a beautiful workshop and installation. The impact of the assembled wall and its ever-changing display is mesmerising, and it delights all ages. We’re not surprised that the new Tinkering Space in @Bristol uses a light wall as a prominent feature.
At Maker Faire UK we observe:
- Broad appeal; families are drawn to the activity, but when there’s clear spare capacity pairs or groups of teens and adults will want to be involved.
- Family groups working collaboratively.
- Dwell times of typically 20 minutes, ±10 mins.
- Lots of back-and-forth revisions and adjustments.
- Discussions around aesthetics, properties of light, narratives, mood…
- With about six work tables, we can work with ~400 people/day.
- Many more people notice and watch the finished display, but we’ve not counted those interactions.
- Two lights per box is about right. Many groups will use just one.
Things we perhaps still haven’t nailed are typically around the available choice of materials, and the nuances of facilitation:
- Too many plastic dinosaurs = ‘Lost World’-themed light wall. A constrained choice of pre-made objects and an abundance of raw materials is probably better.
- Few people try moving the light in front of objects (ie. casting reflected light onto the screen). Similarly, shaping the light by using masks close to the source is fairly rare.
- Go back to the top of this page and look again at the rotating gallery of the Exploratorium’s workshop. Notice the amount of patterned acetate they’re using. It produces beautiful effects, but we’ve found it tricky to entice people to give it a chance.
- The turntables are good, but they don’t prompt a particularly wide range of effects. I’d like to motorised widgets which could be fixed to the top of the box and turn things on strings, or could wave things back-and-forth, or … (etc.)
- High-mounted lights + low turntables = all the movement is at the bottom of the box. There are many ways to fix this, but we need to make some of those solutions more obvious.
Wrapping up
We love this activity. Here’s what it looks like in the hands of secondary students:
Goat on a Boat
Goat on a Boat
A goat? On a boat?!
What’s that got to do with science?
In fact, it’s very scientific when you know that the youngest of the Billy Goats Gruff was actually a naval architect (a boat designer). This little known twist in the old tale has inspired our Goat on a Boat workshop – where we really do float a goat on a boat!
The Workshop
Goat on a Boat has been created to help you explore the world around you, at around Key Stage 1. You’ll practice reasoning skills to develop fair experiments, and from your observations you’ll solve real problems. Real problems like:
Hmm. Perhaps not very real problems. But real enough for the youngest billy goat.
We provide you with the materials to build your raft, some test weights (washers)… and a goat. You could supply your own goat, but ours are carefully trained to be minimal bother in workshops. They’re also small and plastic.
You have to design, build and test a foil boat which is strong enough to float even the youngest goat safely across a river.
- What design will your boat be?
- How will you test your boat? How will you know which is the best design?
- How will you record your observations?
During the workshop, you’ll experience an awful lot of sinking and hopefully a bit of floating as well. You’ll explore which shapes of boat are better than others for keeping goats afloat.
By the end of the workshop you should have a really good idea of how to make a boat that can float. Hopefully, you’ll have made a firm recommendation to your intrepid goat, and will have floated it happily on your boat.
Parents – continue this at home
Nurturing your child’s natural curiosity will help them practice key skills. At home, you could explore the idea of floating and sinking by making simple boats out of aluminium foil (aluminium food trays are particularly good). Try making boats of different designs, and test them in the bath or sink. Use toys to test how much weight they can carry. Why are some designs better than others?
You could also explore whether some objects are buoyant – whether they float. Collect a bunch of things you don’t mind getting wet, and together, make predictions about what you think will float, and what will sink. Then test out your predictions, and try to explain why you got some right, and others wrong.
“Tell me about…” is a particularly useful phrase. It’s a less direct challenge than “Explain this…”. Science is more about what you can observe and describe than what you already know.
Goats aren’t engineers
That’s true. Goats are odd animals, but they’ve never been observed in the wild building rafts. They don’t even seem terribly interested in engineering. However, the skills and processes you practice whilst doing Goat on a Boat, and the areas of science you’re exploring, are similar to the work professional scientists and engineers do. For example:
This goat’s boat wasn’t so successful, and it had to take to a life raft to escape.
Big Mouth Tumblewings
Big Mouth Tumblewings
When the Wright Brothers, Wilbur and Orville, first set out to build a successful aeroplane, they were mocked. People believed it couldn’t be done and, even if it could, there would be no commercial use! The brothers proved their doubters wrong: on the 17th December 1903 they made two successful (if rather short) flights in a powered aeroplane, controlled by a pilot. If you want to find out a little more about the history of flight, have a look at the gallery below. Now it’s your turn to defy convention by building and flying a Big Mouthed Tumblewing, a flying craft unlike any you’ve seen before. Tumblewings are very light spinning shapes that glide – surf, almost – on an updraft of air. There are many designs, but we particularly like this one, designed by Slater Harrison over at the excellent sciencetoymaker.org. Check out this video for tips on making and flying your own.
They’re easy to make, but keeping them airborne is a knack that takes practice. You’ll need open space indoors and lots of perseverance. The film will help you spot the things you’re doing right and wrong.
If you would like to make your own, we have:
-
Tumblewing template (PDF, 1Mb).
Make sure you print full size! - Tumblewing instructions (PDF, 2Mb).
We’ll update this page with a flying training film once we’ve made one we’re happy with – in the meantime, do watch the video above. It’ll help explain what’s going on, and more importantly how to do it yourself.
Our thanks to Slater Harrison for sharing his brilliantly simple tumblewing design with us. Do visit his site!
How (tumble)wings work
Tumblewings are unusual, as wings go. If you look at an aeroplane, you’ll immediately notice one key difference: their wings don’t spin. The same is true of birds, which is probably good for gannets or they’d get terribly dizzy. Helicopter wings do spin, but think about it a little and you’ll notice that they’re not spinning in the same sort of way.
So: Tumblewings. Their spin helps keep them stable, but it also makes them slide forwards through the air as they fall. Walking behind them with a board generates an updraft of air, balancing that fall. Sometimes you’ll see birds – like that happily-not-dizzy gannet – soaring on the updraft at a cliff or hill. They’re doing the same sort of thing, but much more efficiently.
Birds and aeroplanes can glide further than tumblewings because they’re much more efficient wings. Explaining how wings generate lift is a famously subtle challenge. Here’s an animation from Derek Muller of Veritasium, which is about as good as anything we’ve seen.
History of Flight Gallery
When you look at the gliders and aeroplanes the Wright Brothers made, sometimes they don’t look much more advanced than the tumblewing – just a few bits of canvas held apart by some sticks. Perhaps a bit more than a weekend project?
Tag Archive for: workshop
15th March – Wind Turbine Engineering
Well, did your turbine work? Did you manage to get the mass up to the table, or were you left with a knotted bundle of string? Did your turbine purr like a renewable energy generating masterpiece, or did all the blades fall off?
It doesn’t matter either way as long as you didn’t give up: figure out what went wrong and keep trying to fix the problem. As a wise old person once said, “An effective wind turbine was never created by someone who gave up at the first sign of difficulty, like for example the axle being bent.” Isn’t amazing how there’s a wise old saying for almost every eventuality!
Check out more about wind turbines (including a a virtual tour of an offshore wind farm which is awesome) and about careers in the renewable energy sector on our wind turbines activity page.
March 10th – Atoms to Astrophysics
Today we explored the whole scope of Physics, from atoms to astrophysics. For more information check out our workshop page here, and make sure you have a go with this scale of the universe tool. I could spend all day playing around with it.
We talked about protons, neutrons and electrons today, but we didn’t mention the even smaller particles that they are made of. Have an explore. Did you spot the transistor gate that’s about the size of a virus? These are what give your phone its processing power. Current transistors are as small as 7nm – that’s 0.000007mm. The smaller they are, the more we can pack onto a microchip and the more processing power we can get. However, it looks like we might struggle to make them any smaller. As we get smaller we enter the realms of “quantum tunneling” which can cause all sorts of problems. To prevent this, we may have to start making our chips out of something other than silicon. (I like mine made out of potato! ba-dum-tish!)
One option might be a new material invented in Manchester called Graphene. It is only a single atom thick and could be used to make even smaller transistors. It’s super light and super strong and is changing the way we design and construct new products. If you want to get a glimpse of the material of the future, look here.
We also looked at the International Space Station, which you can watch, live, here. If you want to see the ISS fly overhead, use the tracker website here. You can give Tim a wave, and if you tweet him first (@astro_timpeake), he might just wave back!
This article is about Dr Richard Morton who works at Northumbria University. He is studying the sun and its effects on Space weather, which could be used toto help keep astronauts safe whilst in space.
12th Feb – A greener festival
Hello Excelsior! Wow, what a day we’ve just had. I don’t know about you, but it’s made me ready for the summer. I love a good festival: the music, the lights, the food. I’m a bit less keen on the massive expenditure of energy and resources that often goes along with a large music festival. This is why I’m particularly impressed with the Shambala festival which focuses on renewable energy and sustainable resources. They are now powered by 100% renewable energy and have reduced their Carbon footprint dramatically over the last six years. (Find out more information at the bottom of the page.
This music video by Imogen Heap was created using entirely renewable forms of energy. They used a combination of solar hybrid generators and PedGens (fancy exercise bikes – keeps you fit whilst you watch the music!) and were able to power all the music, the stage and the video production equipment. Check out those wired gloves she uses to interact with the music. A perfect example of Science and Art working in perfect harmony.
The activity that we did today is very similar to the sort of research that goes on in the development of wind turbines. You’ve probably seen the large wind turbines either off the coast or up on the hills, but the new breed of wind turbines are designed to work in an urban landscape. Engineers are developing turbines that produce less noise and less vibrations so that we can install them on the tops of buildings and in highly populated areas. Novel designs and structures allow the turbines to be efficient in different wind conditions and produce a consistent level of energy. Vertical axis wind turbines (VAWT) are able to be placed closer to the ground and can operate in less windy areas than traditional wind turbines. You’ll probably see them mostly in urban areas. Next time you’re out in town, take a look up to see if you can see any.
For more information about a regional company who are developing wind turbines check out our Siemens employer case study.
A vertical axis wind turbine at Northumbria University.
12th January: Atoms to Astrophysics
What a great way to start the year; exploring the universe from the incredibly tiny to the unbelievably large. You can find out more about very tiny or very large things using this The Scale of the Universe animation. I could spend all day zooming in and out. We talked about protons, neutrons and electrons today, but we didn’t mention the even smaller particles that they are made of. Have an explore. Did you spot the transistor gate that’s about the size of a virus? These are what give your phone its processing power. Current transistors are as small as 7nm – that’s 0.000007mm. The smaller they are, the more we can pack onto a microchip and the more processing power we can get. However, it looks like we might struggle to make them any smaller. As we get smaller we enter the realms of “quantum tunneling” which can cause all sorts of problems. To prevent this, we may have to start making our chips out of something other than silicon. (I like mine made out of potato! ba-dum-tish!)
One option might be a new material invented in Manchester called Graphene. It is only a single atom thick and could be used to make even smaller transistors. It’s super light and super strong and is changing the way we design and construct new products. If you want to get a glimpse of the material of the future, look here.
We also looked at the International Space Station, which you can watch, live, here. If you want to see the ISS fly overhead, use the tracker website here. You can give Tim a wave, and if you tweet him first (@astro_timpeake), he might just wave back!
6th January: Explore your Universe
Happy New Year, Kenton! What a great way to start the year; exploring the universe from the incredibly tiny to the unbelievably large. You can find out more about very tiny or very large things using this The Scale of the Universe animation. I could spend all day zooming in and out. We talked about protons, neutrons and electrons today, but we didn’t mention the even smaller particles that they are made of. Have an explore. Did you spot the transistor gate that’s about the size of a virus? These are what give your phone its processing power. Current transistors are as small as 7nm – that’s 0.000007mm. The smaller they are, the more we can pack onto a microchip and the more processing power we can get. However, it looks like we might struggle to make them any smaller. As we get smaller we enter the realms of “quantum tunneling” which can cause all sorts of problems. To prevent this, we may have to start making our chips out of something other than silicon. (I like mine made out of potato! ba-dum-tish!)
One option might be a new material invented in Manchester called Graphene. It is only a single atom thick and could be used to make even smaller transistors. It’s super light and super strong and is changing the way we design and construct new products. If you want to get a glimpse of the material of the future, look here.
We also looked at the International Space Station, which you can watch, live, here. If you want to see the ISS fly overhead, use the tracker website here. You can give Tim a wave, and if you tweet him first (@astro_timpeake), he might just wave back!
9th December: Atoms to Astrophysics
This afternoon I visited St Mary’s to take part in their after school science club. We explored the whole scope of Physics, from atoms to astrophysics. For more information check out our workshop page here, and make sure you have a go with this scale of the universe tool. I could spend all day playing around with it.
A slightly older version can be seen below. Don’t be frightened by the outdated fashions and wonderful 1970s music (by Elmer Bernstein, no less!); this video is a beautiful journey through our universe. Just don’t forget, our understanding has moved on since Charles and Ray Eames made this video in 1977.
9th December: More Rollercoasters
This morning, I was back at Kenton for some more K’nex rollercoaster building. There’s a lot that goes into building a rollercoaster, and we only just scratched the surface. For more details, head over to our workshop notes page where you’ll find videos, games, and more information than you can shake a (K’nex) stick at. Now if you’ll excuse me, I have six rollercoasters to dismantle and put back into the correct boxes. Sigh.
4th December: Rollercoasters
How many people does it take to build a rollercoaster? It’s no joke; today we looked at the range of specialists needed to design and construct a rollercoaster, all so that you can get your fix of adrenalin at the local theme park.
I’ve written up some more information on our roller coasters activity page, with a few videos that are worth watching and links to some design-your-own games.
19th November: Space Maths
Today, Carol and James were back at Heworth Grange for more Space Maths. We looked at the size and scale of our solar system (using sprinkles, no less), and got up close and personal with some meteorites.
Find some more information on our space maths workshop page and make sure you check out the link to the “tediously accurate scale model of the solar system”. Seriously, you won’t regret it.
Space Maths and Light Painting
Today, Carol and James visited Heworth Grange to run two workshops.
We did Space Maths – for more on that, check out our page of extra activities. Trust us, you really want to follow the link to the ‘Tediously accurate scale model of the solar system.” No, really.
We also did light and photography: we’ve another page of extra material around light painting, including some jaw-dropping videos. Here are the light painting photos you took in the workshop:
Great to meet you all today. We enjoyed working with you, and hope we’ll be back soon!
