Category: cs4fn issues

Kakuro, Logic and Computer Science

Kakuro Fragment
Part of a Kakuro puzzle. Image by PC

To be a good computer scientist you have to enjoy problem solving. That is what it’s all about: working out the best way to do things. You also have to be able to think in a logical way: be a bit of a Vulcan. But what does that mean? It just means being able to think precisely, extracting all the knowledge possible from a situation just by pure reasoning. It’s about being able to say what is definitely the case given what is already known…and it’s fun to do. That’s why there is a Suduko craze going on as I write. Suduko are just pure logical thinking puzzles. Personally I like Kakuro better. They are similar to Soduko, but with a crossword format.

What is a Kakuro?

A Kakuro is a crossword-like grid, but where each square has to be filled in with a digit from 1-9 not a letter. Each horizontal or vertical block of digits must add up to the number given to the left or above, respectively. All the digits in each such block must be different. That part is similar to Soduko, though unlike Soduko, numbers can be repeated on a line as long as they are in different blocks. Also, unlike Soduko, you aren’t given any starting numbers, just a blank grid.

Where does logic come into it? Take the following fragment:

Kakuro Start - part of a Kakuro puzzle
Part of a Kakuro Puzzle. Image by PC

There is a horizontal block of two cells that must add up to 16. Ways that could be done using digits 1-9 are 9+7, 8+8 or 7+9. But it can’t be 8+8 as that needs two 8s in a block which is not allowed so we are left with just two possibilities: 9+7 or 7+9. Now look at the vertical blocks. One of them consists of two cells that add up to 17. That can only be 9+8 or 8+9. That doesn’t seem to have got us very far as we still don’t know any numbers for sure. But now think about the top corner. We know from across that it is definiteley 9 or 7 and from down that it is definitely 9 or 8. That means it must be 9 as that is the only way to satisfy both restrictions.

A Kakuro for you to try

A Kakuro puzzle for you to try. Image by PC

Here is a full Kakuro to try. There is also a printer friendly pdf version. Check your answer at the very end of this post when you are done.

Being able to think logically is important because computer programming is about coming up with precise solutions that even a dumb computer can follow. To do that you have to make sure all the possibilities have been covered. Reasoning very much like in a Kakuro is needed to convince yourself and others that a program does do what it is supposed to.

– Paul Curzon, Queen Mary University of London

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This article was included on Day 11 (The proof of the pudding… mathematical proof) of the CS4FN Advent Calendar in December 2021. Before that it was originally published on CS4FN and can also be found on page 16 of CS4FN Issue 3, which you can download as a PDF below. All of our free material can be downloaded here: https://cs4fndownloads.wordpress.com/

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The answer to the kakuro above

Answer for the kakuro
A correctly filled in answer for the kakuro puzzle: Image by PC

Cold hard complexity: learning to talk in nature’s language

Gentoo penguin parent with two babies
Penguins image by Clara TCHOUBÉ from Pixabay

A gentoo penguin slumps belly-first on a nest at Damoy, on the Antarctic Peninsula. Nearby some lichen grows across a rock, and schools of krill float through the Southern Ocean. Every one of these organisms is a part of life in the Antarctic, and scientitsts study each of them. But what happens to one species affects all the others too. To help make sure that they all survive, scientists have to understand how penguins, plants, krill and everything else in the Antarctic interact with one another. They need to figure out the rules of the ecosystem.

Working together

When you’re trying to understand a system that includes everything from plants to penguins, things get a bit complicated. Fortunately, ecology has a new tool to help, called complexity theory. Anje-Margriet Neutel is a Biosphere Complexity Analyst for the British Antarctic Survey. It’s her job to take a big puzzle like the Antarctic ecosystem, and work out where each plant and animal fits in. She explains that ‘complexity is sort of a new brand of science’. Lots of science is about isolating something – say, a particular chemical – from its surroundings so you can learn about it, but when you isolate all the parts of a system you miss how they work together. What complexity tries to do is build a model that can show all the important interactions in an ecosystem at the same time.

Energy hunt

So for a system as big as a continent full of species, where do you start? Anje’s got a sensible answer: you start with what you can measure. Energy’s a good candidate. After all, every organism needs energy to stay alive, and staying alive is pretty much the first thing any plant or animal needs to do. So if you can track energy and watch it move through the ecosystem, you’ll learn a lot about how things work. You’ll find out what comes into the system, what goes out and what gets recycled.

Playing with models

Once you’ve got an idea of how everything fits together you’ve got what scientists call a model. The really clever thing you can do with models is start to mess around with them. As an example Anje says, ‘What would happen if you took one group of organisms and put in twice as much of them?’ If you had a system with, say, twice as many penguins, the krill would have to be worried because more penguins are going to want to eat them. If they all run out what happens to the penguins? Or the seals that like eating krill too? It gets complicated pretty quickly, and those complicated reactions are just what scientists want to predict.

The language of nature

Figuring out how an ecosystem works is all about rules and structure. Ecosystems are huge complicated things, but they’re not random – whether they work or not depends on having the right organisms doing jobs in the right places, and on having the right connections between all the different parts. It’s like a computer program that way. Weirdly, it’s also a bit like language. In fact, Anje’s background is in studying linguistics, not ecology. Think of an ecosystem like a sentence – there are thousands of words in the English language but in order to make a sentence you have to put them together in the right way. If you don’t have the right grammar your sentence just won’t make sense, and if an ecosystem doesn’t have the right structure it’ll collapse. Anje says that’s what she wants to discover in the ecosystems she studies. ‘I’m interested in the grammar of it, in the grammar of nature.’

Surviving Antarctica

Since models can help you predict how an ecosystem reacts to strange conditions, Anje’s work could help Antarctica survive climate change. ‘The first thing is to understand how the models work, how the models behave, and then translate that back to the biology that it’s based on,’ she explains. ‘Then say OK, this means we expect there may be vulnerable areas or vulnerable climate regions where you can expect something to happen if you take the model seriously.’ If scientists like Anje can figure out how Antarctica’s ecosystems are set up to work, they’ll get clues about which areas of the continent are most at risk and what they can do to protect them.

Surviving on a continent where the temperature hardly ever gets above freezing is tough, and climate change is probably going to make it even tougher. If we can figure out how Antarctic ecosystems work, though, we’ll know what the essential elements for survival are, and we’ll have clues about how to make things better. Extracting the secret grammar of survival isn’t going to be a simple job, but that’s no surprise to the people working on it. After all, they’re not called complexity scientists for nothing.

Paul Curzon, Queen Mary University of London

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Love your data

A heart icon on a computer keyboard
Computer heart key image adapted from an image by congerdesign from Pixabay

How are you two doing together? You and your data, we mean. It’d be nice to have an update. Do you understand one another in that special OMG-we’ve-talked-all-night-and-now-the-sun’s-up kind of way? Is it more like you just kind of hang out together without really bothering to think about each other? Or maybe you’re just a bit baffled by the whole data scene. If your heart doesn’t beat with fervent love for the wild binary information all around you, that’s OK. In fact that’s pretty normal. It just so happens, though, that there’s a guy who wants to improve your data relationships. He’s called Andy Broomfield and he graduated as a designer from the Royal College of Art.

Andy’s worried that as we rely more and more on gadgets like mobiles and satnavs, a lot of us stop thinking about where the data comes from. “Increasingly we’re becoming dependent on the data,” says Andy. “We are just blindly fed it.” He tells the story of some councils that had to put up ‘Ignore Your Satnav’ signs after lorry drivers followed electronic directions down narrow lanes rather than believe their own eyes. He reckons that hapless users wouldn’t get quite so “data-lost” if we had a way to really connect with the pure information out there, being broadcast from satellites every second of the day. So he designed some gadgets of his own to help get our data relationships back on the rails.

Time to yourself

Large yellow road sign with black text saying Ignore Sat Nav next to an orange and white traffic cone on a foggy road at night well lit by street lighting
Ignore Sat Nav image by Dan Pope on Flickr, used under a CC BY-NC-SA 2.0 licence.

The first device lets you keep a personal time zone, and was inspired by a group of data-lovers who are sweet on measuring time. Time zones divide the globe into long tall ribbons based on longitude. Since GPS satellites can give each of us extremely accurate longitude readings all the time (the cs4fn offices are apparently at .042 degrees west), why not go even further and cut the ribbons up even more? That’s what Andy’s Longitude Time Piece does, to the point where you can uncover what Andy calls “your own local time zone”, right down to the second. Then you’d know that wherever you go, your timing would always be perfect.

Flooded with facts

Andy’s second invention is another GPS-flavoured one. Even though a lot of us can get lost really easily (even with maps and satellites to help), others love getting down and dirty with geographic data. This gadget’s good for both groups. People with a great sense of data direction can use the Geo Flood Browser to get info on the nearest river, wherever they are.

They can also share the love with others who get a bit data-lost, by leaving electronic tags around to let them know if the area gets flooded a lot. Then people nearby can use the tags using their own gadget to find out whether they ought to be stocking up on boats and snorkels before the next flood hits.

Spot a satellite

Finally Andy’s designed a gadget for your data relationships in space. Satellite spotters are kind of like backyard astronomers, except they love catching glimpses of the satellites that orbit the Earth. With Andy’s device anyone can tune into a satellite that’s above them and listen to it. You can either hear a voice tell you about the satellite, or you can actually listen into the bleeps of information coming from the satellite itself. That way, Andy says, you get “a connection to the pure data, the data that we’re dependent upon in the world.” It’s strange to think that this data is around us all the time – it’s just our phones and TVs that normally listen in, rather than us. If information is the lifeblood of our high-tech lives, the Satellite Scanner lets you listen to its heart.

Each of Andy’s devices uses information from the satellites whizzing, Cupid-like, around the Earth. The unusual thing is what they do with it – they’re not about being really useful so much as they are about actually experiencing the data that’s out there in the real world. That’s how he’s aiming to improve our data relationships. It’s like the way you can know someone for ages, but never see what they’re really about until you look from a different angle. Except this time it’s with satellites. Weird, eh? But good. A little like love.

Paul Curzon, Queen Mary University of London

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Delicious computing

Gestural computing with bananas and pizzas…

A photograph of ripening yellow bananas

Bananas image by Couleur from Pixabay

Imagine being able to pick up an ordinary banana and use it as a phone. That’s part of the vision of ‘invoked computing’, which is being developed by Japanese researchers. A lot of the computers in our lives are camouflaged – smartphones are more like computers than phones, after all – but invoked computing would mean that computers would be everywhere and nowhere at the same time.

The idea is that in the future, computer systems could monitor an entire environment, watching your movements. Whenever you wanted to interact with a computer, you would just need to make a gesture. For example, if you picked up a banana and held one end to your ear and the other to your mouth, the computer would guess that you wanted to use the phone. It would then use a fancy speaker system to direct the sound, so you would even hear the phone call as though it were coming from the banana.

Sometimes you might find yourself needing a bit more computing power, though, right? Not to worry. You can make yourself a laptop if you just find an old pizza box. Lift the lid and the system will project the video and sound straight on to the box.

At the moment the banana phone and pizza box laptop are the only ways that you can use invoked computing in the researchers’ system, but they hope to expand it so that you can use other objects. Then, rather than having to learn how to use your computers, your computers will have to learn how you would like to use them. And when you are finished using your phone, you could eat it.

CS4FN team, Queen Mary University of London

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Hiding in Skype

Steganography in a video app

Magic book with sparkly green and purple colours
Magic book image by Yuri from Pixabay

Computer Science isn’t just about using language, sometimes it’s about losing it. Sometimes people want to send messages so no one even knows they exist and a great place to lose language is inside a conversation.

Cryptography is the science of making messages unreadable. Spymasters have used it for a thousand years or more. Now it’s a part of everyday life. It’s used by the banks every time you use a cash point and by online shops when you buy something over the Internet. It’s used by businesses that don’t want their industrial secrets revealed and by celebrities who want to be sure that tabloid hackers can’t read their texts.

Cryptography stops messages being read, but sometimes just knowing that people are having a conversation can reveal more than they want even if you don’t know what was said. Knowing a football star is exchanging hundreds of texts with his team mate’s girlfriend suggests something is going on, for example. Similarly, CIA chief David Petraeus whose downfall made international news, might have kept his secret and his job if the emails from his lover had been hidden. David Bowie kept his 2013 comeback single ‘Where are we now?’ a surprise until the moment it was released. It might not have made him the front page news it did if a music journalist had just tracked who had been talking to who amongst the musicians involved in the months before.

That’s where steganography comes in – the science of hiding messages so no one even knows they exist. Invisible ink is one form of steganography used, for example, by the French resistance in World War II. More bizarre forms have been used over the years though – an Ancient Greek slave had a message tattooed on his shaven head warning of Persian invasion plans. Once his hair had grown back he delivered it with no one on the way the wiser.

Digital communication opens up new ways to hide messages. Computers store information using a code of 0s and 1s: bits. Steganography is then about finding places to hide those bits. A team of Polish researchers led by Wojciech Mazurczyk have now found a way to hide them in a video app (Skype) conversation.

Skype was one of the early popular video call applications, eventually replaced by Microsoft Teams. When you use Skype to make a phone call, the program converts the sounds you make to a long series of bits. They are sent over the Internet and converted back to sound at the other end. At the same time more sounds as bits stream back from the person you are talking to. Data transmitted over the Internet isn’t sent all in one go, though. It’s broken into packets: a bit like taking your conversation and tweeting it one line at a time.

Why? Imagine you run a crack team of commandos who have to reach a target in enemy territory to blow it up – a stately home where all the enemy’s Generals are having a party perhaps. If all the commandos travel together in one army truck and something goes wrong along the way probably no one will make it – a disaster. If on the other hand they each travel separately, rendezvousing once there, the mission is much more likely to be successful. If a few are killed on the way it doesn’t matter as the rest can still complete the mission.

The same applies to a video call. Each packet contains a little bit of the full conversation and each makes its own way to the destination across the Internet. On arriving there, they reform into the full message. To allow this to happen, each packet includes some extra data that says, for example, what conversation it is part of, how big it is and also where it fits in the sequence. If some don’t make it then the rest of the conversation can still be put back together without them. As long as too much isn’t missing, no one will notice.

Skype does something special with its packets. The size of the packets changes depending on how much data needs to be transmitted. If the person is talking, each packet carries a lot of information. If the person is listening then what is being transmitted is mainly silence. Skype then sends shorter packets. The Polish team realised they could exploit this for steganography. Their program, SkyDe, intercepts Skype packets looking for short ones. Any found are replaced with packets holding the data from the covert message. At the destination another copy of SkyDe intercepts them and extracts the hidden message and passes it on to the intended recipient. As far as Skype is concerned some packets just never arrive.

There are several properties that matter for a good steganographic technique. One is its bandwidth: how much data can be sent using the method. Because Skype calls contain a lot of silence SkyDe has a high bandwidth: there are lots of opportunities to hide messages. A second important property is obviously undetectability. The Polish team’s experiments have shown that SkyDe messages are very hard to detect. As only packets that contain silence are used and so lost, the people having the conversation won’t notice and the Skype receiver itself can’t easily tell because what is happening is no different to a typical unreliable network. Packets go missing all the time. Because both the Skype data and the hidden messages are encrypted, someone observing the packets travelling over the network won’t see a difference – they are all just random patterns of bits. Skype calls are now common so there are also lots of natural opportunities for sending messages this way – no one is going to get suspicious that lots of calls are suddenly being made.

All in all SkyDe provides an elegant new form of steganography. Invisible ink is so last century (and tattooing messages on your head so very last millennium). Now the sound of silence is all you need to have a hidden conversation.

Paul Curzon, Queen Mary University of London

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Naked Mole-Rats Go Digital – monitoring colonies remotely (while respecting their privacy)

Wanted poster for a masked Naked Mole Rat WANTED Naked Mole Rat Reward for any Information
Image by CS4FN

Where does a naked mole-rat wear its computing gadgetry? Under its skin….

Naked mole-rats are fascinating creatures. They are highly social, living in colonies. They spend their lives permanently underground in burrows, and that’s why they have no fur just whiskers. They don’t need it. Living underground means they are difficult to study. Normally researchers simply watch animals to study their behaviour, but that’s not possible for naked mole-rats.

Tag ’em

To allow them to be observed, one colony of 28 animals, called Colony Omega, went digital. They all have an implant under their skin. These tags are just smaller versions of ones used by vets to tag pets. Sensors around their burrow detect when the tags are close. This means the naked mole-rats can be watched in real-time as they move around the burrow. It’s allowing the biologists to study patterns in their behaviour such as how different animals take on different roles in the colony.

Interactive rat art

Julie Freeman, an artist and computer scientist at QMUL, used the same data in a different way. She leads a team creating interactive art based on the naked mole-rat data. ‘A Selfless Society‘, for example, is an abstract animation that changes as a result of the live data from the colony. The sculpture ‘This is Nature Now‘ also represents the live data from the colony but using soft robotic techniques (see page 13 of the magazine linked below). It moves based on the movements of the naked mole-rats. We often experience nature through technology, watching it on screens rather than in real-life. ‘This is Nature Now’ explores how physical, non-living objects can convey a sense of life.

Private portraits

Colony Omega also has its own gallery of portrait photos, taken by Lorna Ellen Faulkes. The eyes of the naked mole-rats are blocked out (to protect their identity!) The idea is to make people think about data privacy. Technology raises big issues over our own privacy. We now give away vasts amount of personal information without realising. What about the data privacy of animals?

This may seem silly, but is a very real problem. Tourists posting images of endangered animals and plants on social media from safaris has caused problems. It has led poachers to the animals and plants photographed, putting them in serious danger. The problem arises because modern digital cameras log the place a photo is taken, and this ‘metadata’ is included with the photograph posted for anyone to see who knows where to look.

Paul Curzon, Queen Mary University of London

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This article was originally published on the CS4FN website and a copy can also be found on page 6 of Issue 25 of CS4FN, “Technology worn out (and about)“, on wearable computing, which can be downloaded as a PDF, along with all our other free material, here: https://cs4fndownloads.wordpress.com/  

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The heart of an Arabic programming language

‘Hello World’, in Arabic

A colourful repeating geometric pattern
Geometric pattern by aaron_blonde from Pixabay

So far almost all computer languages have been written in English, but that doesn’t need to be the case. Computers don’t care. Computer scientist Ramsey Nasser developed the first programming language that uses Arabic script. His computer language is called قلب. In English, it’s pronounced “Qalb”, after the Arabic word for heart. As long as a computer understands what to do with the instructions it’s given, they can be in any form, from numbers to letters to images.

Paul Curzon, Queen Mary University of London

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Chocoholic Subtraction

Make an edible calculating Turing machine subtract

A delicious uneven tower of broken chocolate bars with dark chocolate, white chocolate and milk chocolate.
Image by Enotovyj from Pixabay

We saw in the previous article that a Turing machine can be used to do any computation, as long as you get its program right. Let’s create a program to do something simple to see how to do it. Our program will subtract two numbers.

The first thing we need to do is to choose a code for what the patterns of chocolates mean. To encode the two numbers we want to subtract we will use sequences of dark chocolates separated by milk chocolates, one sequence for each number. The more dark chocolates before the next milk chocolate the higher the number will be. For example if we started with the pattern laid out as below then it would mean we wanted to compute 4 – 3. Why? Because there is a group of four dark chocolates and then after some milk chocolates a group of three more.

M M M D D D D M M D D D M M M M …

(M = Milk chocolate, D = Dark chocolate)

Here is a program that does the subtraction if you follow it when the pattern is laid out
like that. It works for any two numbers where the first is the bigger. The answer is given
by the final pattern. Try it yourself! Begin with a red lolly and follow the table below.
Start at the M on the very left of the pattern above.

Instructions table for Chocolate Turing Machine
Table by CS4FN

From the above starting pattern our subtraction program would leave a new pattern:

M M M D M M M M M M M M M M M …

There is now just a single sequence of dark chocolates with only one chocolate in it.
The answer is 1!

Try lining up some chocolates and following the instructions yourself to see how it works.

Paul Curzon, Queen Mary University of London

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Chocolate Turing Machines (edible computing)

A delicious looking box of chocolates
Image by congerdesign from Pixabay

Could you make the most powerful computer ever created…out of chocolates? It’s actually quite easy. You just have to have enough chocolates (and some lollies). It is one of computer science’s most important achievements.

Imagine you are in a sweet factory. Think big – think Charlie and the Chocolate Factory. A long table stretches off into the distance as far as you can see. On the table is a long line of chocolates. Some are milk chocolate, some dark chocolate. You stand in front of the table looking at the very last chocolate (and drooling). You can eat the chocolates in this factory, but only if you follow the rules of the day. (There are always rules!)

The chocolate eating rules of the day tell you when you can move up and down the table and when you can eat the chocolate in front of you. Whenever you eat a chocolate you have to replace it with another from a bag that is refilled as needed (presumably by Oompa-Loompas).

You also hold a single lolly. Its colour tells you what to do (as dictated by the rules of the day, of course). For example, the rules might say holding an orange one means you move left, whereas a red one means you move right. Sometimes the rules will also tell you to swap the lolly for a new one.

The rules of the day have to have a particular form. They first require you to note what lolly you are holding. You then check the chocolate on the table in front of you, eat it and replace it with a new one. You pick up a lolly of the colour you are told. You finally move left, move right or finish completely. A typical rule might be:

If you hold an orange lolly and a dark chocolate is on the table in front of you, then eat the chocolate and replace it with a milk one. Swap the lolly for a pink one. Finally, move one place to the left.

A shorthand for this might be: if ORANGE, DARK then MILK, PINK, LEFT.

You wouldn’t just have one instruction like this to follow but a whole collection with one for each situation you could possibly be in. With three colours of lollies, for example, there are six possible situations to account for: three for each of the two types of chocolate.

As you follow the rules you gradually change the pattern of chocolates on the table. The trick to making this useful is to make up a code that gives different patterns of chocolates different meanings. For example, a series of five dark chocolates surrounded by milk ones might represent the number 5.

See Chocoholic Subtraction for a set of rules that subtracts numbers for you as a result of shovelling chocolates into your face.

Our chocolate machine is actually a computer as powerful as any that could possibly exist. The only catch is that you must have an infinitely long table!

By powerful we don’t mean fast, but just that it can compute anything that any other computer could. By setting out the table with different patterns at the start, it turns out you can compute anything that it is possible to compute, just by eating chocolates and following the rules. The rules themselves are the machine’s program.

This is one of the most famous results in computer science. We’ve described a chocoholic’s version of what is known as a Turing machine because Alan Turing came up with the idea. The computer is the combination of the table, chocolates and lollies. The rules of the day are its program, the table of chocolates is its memory, and the lollies are what is known as its ‘control state’. When you eat chocolate following the rules, you are executing the program.

Sadly Turing’s version didn’t use chocolates – his genius only went so far! His machine had 1s and 0s on a tape instead of chocolates on a table. He also had symbols instead of lollies. The idea is the same though. The most amazing thing was that Alan Turing worked out that this machine was as powerful as computers could be before any actual computer existed. It was a mathematical thought experiment.

So, next time you are scoffing chocolates at random, remember that you could have been doing some useful computation at the same time as making yourself sick.

Paul Curzon, Queen Mary University of London

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Microwave health check

Using wearable tech to monitor elite athletes’ health

Blue and yellow sine wave patterns representing light
Image by Gerd Altmann from Pixabay

Microwaves aren’t just useful for cooking your dinner. Passing through your ears they might help check your health in future, especially if you are an elite athlete. Bioengineer Tina Chowdhury tells us about her multidisciplinary team’s work with the National Physics Laboratory (NPL).  

Lots of wearable gadgets work out things about us by sensing our bodies. They can tell who you are just by tapping into your biometric data, like fingerprints, features of your face or the patterns in your eyes. They can even do some of this remotely without you even knowing you’ve been identified. Smart watches and fitness trackers tell you how fast you are running, how fit you are and whether you are healthy, how many calories you have burned and how well you are sleeping or not sleeping. They also work out things about your heart, like how well it beats. This is done using optical sensor technology, shining light at your skin and measuring how much is scattered by the blood flowing through it.  

Microwave Sensors

With PhD student, Wesleigh Dawsmith, and electronic engineer, microwave and antennae specialist, Rob Donnan, we are working on a different kind of sensor to check the health of elite athletes. Instead of using visible light we use invisible microwaves, the kind of radiation that gives microwave ovens their name. The microwave-based wearables have the potential to provide real-time information about how our bodies are coping when under stress, such as when we are exercising, similar to health checks without having to go to hospital. The technology measures how much of the microwaves are absorbed through the ear lobe using a microwave antenna and wireless circuitry. How much of the microwaves are absorbed is linked to being dehydrated when we sweat and overheat during exercise. We can also use the microwave sensor to track important biomarkers like glucose, sodium, chloride and lactate which can be a sign of dehydration and give warnings of illnesses like diabetes. The sensor sounds an alarm telling the person that they need medication, or are getting dehydrated, so need to drink some water. How much of the microwaves are absorbed is linked to being dehydrated

Making it work

We are working with with Richard Dudley at the NPL to turn these ideas into a wearable, microwave-based dehydration tracker. The company has spent eight years working on HydraSenseNPL a device that clips onto the ear lobe, measuring microwaves with a flexible antenna earphone.

A big question is whether the ear device will become practical to actually wear while doing exercise, for example keeping a good enough contact with the skin. Another is whether it can be made fashionable, perhaps being worn as jewellery. Another issue is that the system is designed for athletes, but most people are not professional athletes doing strenuous exercise. Will the technology work for people just living their normal day-to-day life too? In that everyday situation, sensing microwave dynamics in the ear lobe may not turn out to be as good as an all-in-one solution that tracks your biometrics for the entire day. The long term aim is to develop health wearables that bring together lots of different smart sensors, all packaged into a small space like a watch, that can help people in all situations, sending them real-time alerts about their health.

Tina Chowdhury, Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London

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