How does camouflage work?

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Right now I'm on an unlikely mission. I'm scrambling through a thicket of trees and bushes in a patch of forest just on the outskirts of Prague in the Czech Republic. Big branches. Let's do this. Big steps. Well, I say forest. It's more of a public park. There's a couple walking their German Shepherd just over there. There's a bank of portaloos by the entrance. But this bit that I'm scrabbling through, it's quite foresty.

Currently hiding behind a tree. It is very hot. It's around 34 degrees Celsius today. And I'm entirely cloaked head to toe in a thick military-grade ghillie suit. I am warm. I'm gonna find somewhere to hide. Okay, I got it. I got it. This is perfect. Let me just... Yeah. They're not going to be able to see me here. I'm Alex Lathbridge and this is CrowdScience from the BBC World Service, the programme that takes your science questions and searches for an answer.

Even if they're really hard to find. I'm invisible. Can't see me. This week, I'm following the trail of a question from listener Paul in Uganda. Okay, my name is Paul Matovu. I come from Uganda in the capital Kampala. I'm a botanist. That is my passion, nature. Okay, what? was the question that you wrote in to us about yeah my question was about the origin of camouflage combat wear

How did it originate and how did it spread to most of the modern armies in the world? What is the essence behind it? Why does the combat way have to look the way? It does with the shades of green. So that was my question. And so what made you so curious about this question? It's, you know, right now there are so many wars going on.

you will see these fighters some of them are looking very young and they are clad in these uniforms it gives them an air of authority or invincibility that they wouldn't necessarily have if they didn't have the uniform on would fighting be different if we didn't have these types of uniforms. And so why do you think that these uniforms are the blue-green colour?

So I thought that it's about camouflage in this sort of environment where warfare is supposed to take place from in the forest, in the grasslands. But why is it even being used in modern warfare? Because in a country where I come from, at times we get riots and then they have to bring in the army sometimes to maintain law and order.

they come with exactly the same wear that does not give any camouflage advantage which got me thinking what is the use of wearing shades of green in the middle of the city in the urban setting really doesn't make sense and me who comes from the background of nature forests plants I've been fascinated by the green shades of these combats. It seems that you know about this. You know about the outdoors world. I mean, tell me, what sort of camouflage have you seen in the animal kingdom?

Yeah, in the animal kingdom it's really diverse. We have a common snake in Uganda. It's a green snake and we grow a lot of bananas. And it loves to be in the green leaves because that is why it blends better. And you cannot see the snake. And of course, we have animals like the chameleon who even go an extra mile of changing their color depending on where they happen to be.

So I guess this is something that we've picked from the Animal Kingdom. Even for the Amis, they must have picked it from the Animal Kingdom. But it's something that I would rather want to find out more about. Okay. So where did the designs for modern military camouflage come from? How do they work? How do they conceal soldiers in the forests or the deserts where they carry out their duties?

And why do they still wear them in cities where they stick out like a sore thumb? Those are great questions Paul. His intuition is that the design must have been inspired by the natural world, where camouflage is everywhere. And I think he might be onto something. So you have to remember that the game is to survive. Not necessarily not to be seen. I mean, that's very much correlated with it. But the game is to survive.

Here's someone who can help me find some answers. Laszlo Tallis from CamoLab at the University of Bristol here in the UK. CAMO lab is a research lab that exists between biological sciences, psychological science and the vet school as well. We primarily look at animal coloration with sometimes the human aspect as well. Laszlo's taking me through some of the many and varied ways that animals manage to hide themselves in the wild.

There are many different types of camouflage that could be olfactory, like hiding your smell. There is also audio camouflage, but let's just stick with visual camouflage. One strategy is background matching. Animals can sort of blend into their backgrounds. So you look at the scene, if you're a predator, you're not even aware that there is a tasty insect there. There is also another form where...

You don't recognize the object as an object of interest. So that is typically mimicry. Kind of like a stick insect. A stick insect. Yes, yes, yes. or a caterpillar camouflaging itself as bird poo basically so who wants to eat bird poo right Laszlo's work isn't restricted to the natural world. Work that he did for his PhD looked at the cultural evolution of military camouflage.

in the social effect of camouflage and how these patterns could have influenced each other. Let's start with some history. Armies haven't always wanted to conceal themselves have they?

Yes, that's very true. For most of human history, soldiers want it to be easily recognizable. When you are fighting up close, there is no point of hiding yourself. You have to go to your... opponent to fight them. And in that case it's very important to tell apart who is who. And hiding yourself was considered ungentlemanly.

The British military was wearing very bright red. This changed when long-distance firearms became the most commonly used weapon. So one of the first attempts to camouflage on mass scale... was actually khaki in india and what soldiers did is they had very nice white garments they colored it with tea or put it in mud and it got that sort of brownish color When did we start getting the camouflage that is so famous today, that green and black colouring? The first pattern...

mass-produced was done by the Italians it's called Tello Mimatico and if I remember right it was around 1929. After it was invented it quickly spread to the armies of other nations. By the Second World War Lots of armies were using a blobby brown and green patterned uniform. But just as quickly, they discovered a problem. With every soldier wearing camouflage, suddenly you couldn't tell who was who. Friend?

Enemy? Tree? When you turn around the corner and you see somebody standing there and you have milliseconds to make a decision that could cost your life. So that's why armies tend to develop. patterns that look different from their opponents. For his PhD research, Laszlo collected as many examples of these different camouflage patterns as possible from all parts of the world and all eras.

He's got over 600 of them stored on a massive database on his computer. Most of them are some variation on the classic green and brown blob situation that you'll be familiar with. but some of them are really different. Dare I say it, sort of beautiful. So this one was worn by Romanian special forces back in perhaps 60s, 70s.

So this pattern that we see here is called the parsley pattern because it just looks like a collection of green parsley leaves, the stuff that you would put in soup, basically. Picture delicate sprigs of artistically painted green leaves on a creamy pale background. It looks like very expensive wallpaper. Sometimes a bit more abstract. So this was sort of like pixelated leaves. This is the 60s Soviet Union. Pea pattern from Austria. There you go. This looks like spilled peas.

Amoeba pattern. I think this was perhaps one of the first patterns they used in the Second World War. It just looks like a spilled paint, right? It looks like a very difficult puzzle piece. You know. Well, talking about puzzle pieces, so we got several generations of Belgian jigsaw patterns. So over the years, countries were able to develop their own sort of style.

Some countries went even further. They used their unique camo pattern as an opportunity to show a bit of national pride. Here is a pattern from... Jordan, a modern pattern. But what is particular about this pattern is this little shape here. It looks like a little arrow. This is the shape of Jordan. Oh. This is a modern pattern from Croatia. And if you look at this shape, this is the outline of Croatia with all its islands. Right. Okay. So countries are actively putting pictures of their nation.

in little sections of the camouflage. as low easter eggs that's correct i don't think this has anything to do with concealment this is just an easter egg for soldiers to know that oh you are actually wearing the shape of your country there is a sort of hidden message there Now our listener Paul wanted to know why...

He sees soldiers that come into his city in urban environments still wearing this green forest camouflage. Why could that be? Yes, so that observation is very valid. just going back to the signaling aspect in many cases the army potentially wearing camouflage just to be recognized as the army so it becomes a signature and at that point it doesn't really matter whether it's a matching camouflage or not

That's a really good point. Those soldiers that Paul sees on the streets of Kampala aren't actually trying to hide at all. They're trying to be as visible as possible. As much as they potentially want to threaten. people in certain scenarios, they want to impress, they need recruits. So it's just going back to the ultimate history of military garment is it also needs to impress the next generation.

It's incredibly complex. And like with that in mind, what do you think the future of camouflage could be? There is quite a lot of research happening now against artificial observers, you know, being spotted by drones. And we're probably moving towards a sort of Terminator-like scenario that there's going to be more and more robots and artificial beings out in the battlefield.

Yes, I mean, thermal cameras have been around for a while and it's a big focus of the military to camouflage themselves in the thermal spectrum. So it is a massive, massive challenge. You know, when I was a soldier, it was usually battlefield somewhere in Iraq, Afghanistan. So it was different, a huge difference between the NATO forces and the enemy. Now... on the ukrainian battlefield they use more and more these drones and electronic devices which make all the fighting different

If I've learned anything from sci-fi movies, it's this. When the enemy changes how they hunt for you, you have to change how you hide. i still remember the first terminator when these machines are killing the people it's happening now you can see drones dropping down bombs and grenades they they don't have a clue there is something hanging 500 meters above them

We are trying to protect soldiers from these machines. Here I am back in Prague. I'm not in the woods and in a ghillie suit just yet. Right now, I'm nosing around the workshop of the company who makes it, 4M Tactical. Here's Radek, their CEO. I'm Radek Duchek, CEO of the Forum Tactical Company. Trying to do our best to supply mostly special forces on the world with the stuff they would really appreciate.

4M manufacture high-tech gear for the military. Things like backpacks, ballistic armour, helmets or high-tech jackets. Radek is an ex-soldier himself, so he knows what he's talking about. Me, as an ex-soldier and retired Special Forces guy, I believe I still have some experiences to shape it and to make it in the way they will really like it.

They can just be focused on the mission. That's our task. I've come here to see just one of their latest inventions. It's a cloak that promises to make soldiers disappear. Not just to the human eye. but also to the roving, thermal eyes of autonomous drones. We make soldiers invisible so they look like the surrounding trees or ground, so the machines cannot see them.

Is this the poncho? This is the thing which makes you invisible for the drones. They call it a cloak or a poncho, but that doesn't do it justice. It's a whole outfit. Imagine a huge hooded cape that comes down to the knees and two leg parts which wrap around and clip on. When you're stood in front of it, the most striking thing is the top layer. It's a ghillie suit covered in stringy bits of green and brown fabric. Imagine Cousin It from the Addams Family, but made out of a bush.

yeah we are adding different colors and types of fabrics to just scatter the shape of the human body so if you would stay like 20 meters from it in the green forest it would be invisible But the real magic is several layers beneath the foliage, because that's where the thermal camouflage is. This material is Infrahex laminate. It feels...

This feels like a normal jacket, but this is cutting-edge nanofiber technology. Yes, so it lets all the moisture come out and at the same time it protects you from the rain and makes you invisible. Now, hiding something in the infrared spectrum is no small challenge. If any of your body heat escapes the cloak, you'll be immediately visible to the infrared cameras.

And if your body heat can't escape, well, let me tell you, you'll cook. If we would just block the heat, that would overheat the user very, very fast. So it's actually a combination of some layer which is... changing that wavelength but there are also layers which are nanofibers and in the combination we have something very breathable water resistant but at the same time making the thermal camouflage

To solve that problem, they're using a fiber which releases the heat but changes its wavelength as it goes so it's no longer visible on infrared cameras. To make it, They've partnered with nanofiber company Respilon and Matej Buzgo is their chief technology officer. Yes, hi, my name is Matej Buzgo and I am CTO of InfraHacks company. part of a respilon group. How does this work? The nanofiber membranes are having very important function to homogenously dissipate the heat over the surface.

so we don't enable to build up the heat so we are permeable for the heat but the infrared cameras are not able to see it so thanks to this you are having an ultimate a thermal comfort and thermal concealment in the same time Okay, how do you get rid of heat? Because we're standing right now here in Prague. It is 31 degrees Celsius. I know this because I am leaking.

water. I'm very glad that none of you have mentioned it. How do you get rid of heat? The heat in form of radiation, thanks to the special coating and special metalized textile. is not emitted in a wavelength, in a spectrum, which would be visible for the camera. We are emitting and dissipating in different parts of the spectrum, so it became invisible for the thermal camera.

If we would use a foil, which would be impermeable, this would result in a very fast heat buildup and the soldier would cook himself. So it was a lot of development, a lot of prototypes, a lot of iterations, a lot of luck, where we are able to find the combination.

Why did you develop this technology? The key motivation to develop the technology was connected with what happened in Ukraine. At the beginning the drones were not really used except just some scouting around to just see what's going on. As it started to evolve it become the biggest threat for most of the soldiers over there. And we wanted to respond somehow. So this was the motivation at the start. Okay, so these ponchos, right? How do you test them?

as everything first what is made here we test in the nearby forest just you know to see if everything works as it should and then the later tests we send it to the soldiers to units and we ask for their opinion. If they like it, we go to the cereal production. What does testing out here look like? I'm imagining you wearing one of these ponchos, going out into the forest. and all of your staff, maybe you haven't paid people on time this month, go find him. Where is he? How do you test this?

Exactly as you described, actually. And I believe our neighbors are sometimes quite shocked because they are seeing people walking in the uniforms with the thermal goggles or in these cloaks. Can I test it out? Of course, let's go to the forest. So far in the show, we've discovered where the brown and green blobs of military camouflage come from and how they work to fool your eyes. Now... I'm getting suited up in a high-tech cloak to see if I can fool the eyes of the thermal cameras as well.

I'm Alex Lathbridge and you're listening to CrowdScience from the BBC World Service, the show that peers through the binoculars of science to unearth the answers to your questions. And today I'm on a quest from Paul in Uganda. to find out how military camouflage works okay you i will let you dress it this way you just step on this right this is for your right uh oh it has to be the right leg i step on this with my heel i wrap this round i wrapped it the wrong way actually you did it right

I know the point of this suit is that it keeps soldiers relatively cool, but you know what? It's 34 degrees today here in Prague and I am sweating. We call it gators. It's like a sleeve for your leg look a little bit like a cowboy pants I'm not admitting on the world service. I'm wearing chaps

Okay, so now that I'm suited and booted, Radek and the team have got the thermal cameras out and they're trained on me. Here are the goggles. Thank you. Are you ready to disappear? Let's see, how do I look? Producer Emily wants to make sure that we're testing this thoroughly. Do you want to go into the actual forest and like crouch down? I want to see if we can lose you.

You want to lose me? Yeah. The BBC CrowdScience Risk Assessment. Did you have losing presenter in the thermal spectrum? Was that in there? So now we are starting drawing. with a thermal camera and Alex will be walking in the park and we will see how this works in this temperature. Alex will be doing that, that's what Alex will be doing, okay. things I do for you people. Now if you look at the screen and you imagine you are the drone operator, can you try to find Alex on the screen?

Now we can see one guy who is like 30% visible, half of his body. And next to him is Alex and he is grey as leaves and grass around him. So now it works 100% perfect. Alex is almost invisible. From 50 meters where usually drones are used. they have no chance to find alex great alex you're invisible how do you feel because you say i'm invisible yeah but i feel very visible

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Find out more at bbc.com slash join Of course there may well be lots of incredibly cool camouflage technology out there but and you're going to let me have one pun here, we just can't see it. The vast majority of it is developed by military forces, and most of them are pretty tight-lipped about what they have up their sleeves.

I think the squirrelling away of technology by states is inevitable. However, if we can develop technology that is equally cool, but people can actually see it, I think that's a really good thing to do. Not all camouflage is made by or designed for the military. There's some technology that's available to the common man.

Well, one of our missions is to make sure that the coolest stuff that is developed doesn't just belong to government organizations. I think the more that technology is hidden away, the less power it has to do good. So hello, my name is Steve Tidball and I'm the CEO and co-founder of Volaback. So Volaback is a material science company that I started with my twin brother.

And currently we make what we describe as clothes from the future. And so we make things that might shield you from electromagnetic frequencies or jackets made out of copper that have disease-resistant properties. Another good example would be our marsh.

aerogel jacket, which is built out of hypersonic space parachutes that landed the last rovers on Mars. I mean, a really good example would be our electromagnetic shielding suit, which is designed to shield you from everything from Wi-Fi and infrared to sort of satellites. Now we're here to talk about one specific piece of clothing, your thermal camouflage jacket. So what is it?

So the thermal camouflage jacket was a concept piece we created with the University of Manchester that could effectively disguise how hot or cold it looked under an infrared camera. OK, so what does this jacket look like? It looks something like a white lab coat. And on the front of that lab coat are a series of about 30 dark grey squares.

Each of those dark grey squares is made out of a hundred layers of graphene and is connected electrically to a battery pack which is then wired up to a computer. Unlike the 4M thermal cloak. These graphene patches are powered. You have to plug them in. So if this prototype is to make it onto the streets, it'll need batteries. But what that does mean is that the patches can be individually programmed. You can switch some on and some off or create patterns or shapes in the infrared spectrum.

we can effectively control how hot or cold it looks. The key to the magic is the material that it's made out of, graphene. So graphene is a single layer. of carbon atoms, and graphene in its purest form is the strongest and most conductive material.

in the world. The reason we used graphene in this particular jacket is because graphene is what's called a tunable on the infrared spectrum. So if you push electrical current through it, you can make it look like a different temperature than it actually is. In our program, we've been looking at camouflage in the context of the military. In the military, people need to disguise themselves for obvious reasons. But your stuff is streetwear. It's designed for ordinary people.

Why do you think that ordinary people might be interested in, say, thermal camouflage? Well, I think this really gets to what is your view of what the future is going to look like. It would appear that we are... entering a more surveilled time than at any other time in history and that that is only going to increase and anonymity and sovereignty

of your own image and identity is going to become increasingly prized. I don't want to become like a sort of urban warrior fighting the surveillance state. I think you end up in a very weird world if you do that. The thermal camouflage jacket was

as much a thought experiment as anything else. It was what are the materials we would need to use and what are the techniques we would need to use in order to be able to build this stuff and how this might serve things that are sort of 10 years down the line. Our listener, Paul, he was really interested in the concept of urban camouflage. So if Volaback were to tackle the challenge of urban camouflage, disguising yourself in an urban environment, how would you go about it?

I think in terms of urban camouflage, you really have to think about what you're actually trying to disguise yourself from. I really think what you're actually talking about is disrupting the ability of sensor systems to detect you. and the sensor system is no longer actually the human eyeball looking for you. It's much more likely to be some form of pervasive technology.

be it a drone the size of a bee with a camera or some kind of infrared equipment. So I think painting bricks on your chest and hiding next to a brick wall, for instance, would be an absolutely terrible idea. And I think you really have to think sensor systems. first. So you and I could be walking down the street. You know, you're wearing some Volaback gear that's hiding you from the infrared spectrum. Someone walking down the street can see us the same way, but...

the sensors, they'll see you sort of as a void as a black hole. Is that sort of what you're thinking? Yes. And so to a normal human walking past us, we essentially look identical. But to some kind of pervasive surveillance operating system, we might look like there's only one of us. It's equally very, very cool. And very, very scary, you know? Yes, it's really interesting designing for the future because I'm very hopeful about the future.

But at the same time, I'm a sort of realist. I personally hate the idea of any kind of surveillance state, the idea of being perennially watched. But when you're designing for the future, you have to wear two hats, which is one is a hopeful technologist hat. And the other is a kind of realist hat where you look at what trends are happening and what you could design to cope with them.

So, we can hide soldiers in the visual spectrum by using patterned camouflage, and if you want some extra oomph, textured ghillie suits. And there are various emerging technologies out there to hide them in the infrared spectrum as well. But we still haven't quite answered Paul's question of how we can hide in the bright lights and concrete jungle of the city. Maybe we need to go back to the natural world for some more inspiration.

We have been looking at chameleons and also other animals like octopus that can change color. We cannot take those animals and copy their technology, but we can very much be inspired by them. This is Hans Carice, Deputy Research Director at the Swedish Defense Research Agency, FOI. The chameleon and the octopus, they are using organic

pigments to change. We are more into looking at electronic components to make this transition. Hans and his colleagues worked on a project that launched back in 2018. looking at adaptive camouflage. So camouflage that has the ability to change when you want it to, to better suit the environment that you happen to be in. A real life chameleon suit.

The project was called Adaptive Camouflage for the Soldier, or ACAMS II. We have a textile base. In this textile built in electronic components that can change the color. We built in... radar absorbing materials and we build in infrared camouflage. The project investigated lots of futuristic tech, infrared reflective pigments or nanostructures made of photonic crystals. One technology they used is a little more familiar to you and me.

LEDs. So we have integrated the light emitting dyes into textile to get the uniform to change color. on request for example from green in the forest to gray in a built-up area to more red or orange that could be a forest in october for example now i know what you're thinking because i'm thinking as well LEDs. Those are like the spotlights in my bathroom or the things behind my television screen. Things that are in my Christmas lights.

Surely wrapping a soldier in shimmering fairy lights is the last thing that you want to do. Well, these aren't quite like the LEDs that you and I have in our homes. For starters... They're far less bright. The important thing for us is the color, not the brightness. We want low brightness, but good opportunity to change the color.

So I'm trying to imagine what it might look like in my head and I can't quite picture it. What would it look like? Ideally, it will not look like anything. You will not see it at all. Well done. You got me. It would look like an array of LEDs integrated into the fabric, so you wouldn't see the individual LEDs. You would see the fabric. The actual uniform was having a color.

Is it something that the soldiers would control? Is it something that could be controlled externally? How would this work? We don't want to increase the cognitive burden of the soldier. high enough already. So that has to be an automatic system. We have some kind of sensor and transfer that information to this adaptive camouflage system on the soldier. We also

know that the soldier wants to be able to turn it off completely. You don't want to be in a situation where some kind of malfunction of the system so that the soldier starts twinkling like a Christmas tree. It has to. be like an emergency stop button to turn the whole system off. This is very new technology and is a way off from being rolled out to troops just yet. But color-changing chameleon soldiers could be a thing of the future. There are also legal aspects on this.

Of course the perfect camouflage in a city would be to dress up like you and me in the everyday civilian clothes. But that is not allowed. That would be a war crime to do that. You have to be able to see that this is a soldier or not to be seen at all. It's not a war crime to be invisible but it is a war crime to look like a civilian. Is developing camouflage like a bit of an arms race? Do opposing forces develop systems for detection just as fast as you can develop systems to conceal? Yes.

Exactly, it is exactly like that. And right now I would say that opponents, that's also my colleagues in the other corridor to develop sensors, they are right now ahead of us. sensors are becoming smaller and cheaper so they can be put on drones and that means that even at night we cannot be safe. A couple of years ago Soldiers could move from one position to another at night and rely on that the enemy couldn't see them. But that's not the case with infrared sensors on drones.

We are working very hard on developing the camouflage to be able to counter also the most modern sensors. So there you have it, Paul. There are, in fact, many reasons why soldiers wear camouflage. To hide, yes, but also to be seen, for prestige and a show of authority. As for the camouflage itself... Those familiar mottled green patterns might be good in the forest, but they're no help at all in the face of some of the tools of modern warfare. Autonomous drones loaded with infrared sensors.

night vision goggles or radar scanners. As quickly as an enemy develops new ways to find you, with the power of science we have to find new and more ingenious ways to hide. Thank you so much for your question, Paul. So take it away with the credits. That is all from this episode of CrowdScience from the BBC World Service. This week's question was from me.

Paul Matovo from Uganda. The show was presented by Alex Lathbridge and the producer was Emily Knight. If you have a question on any subject and you want the team to investigate, why not email crowdsales at bbc.co.uk. Goodbye. Thank you. At the BBC, we go further so you see clearer. Through frontline reporting, global stories and local insights, we bring you closer to the world's news as it happens. And it starts with a subscription to BBC.com.

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