Fast-forward to 2018 and millions of people still don’t have access to the technology they need. It turns out losing a limb is far more common than people realise; according to the World Health Organisation, there are 40 million amputees in the developing world. Just 5% of these have access to any form of prosthesis.

A number of teenage inventors are already tackling this challenge, however. Though in many countries they’re too young to drink, drive, or vote, they are already inventing low-cost solutions for those in need.

Take 19-year old Shiva Nathan, an undergraduate research assistant at Carnegie Mellon University, Pittsburgh. He spent his childhood playing video games, which was surprisingly useful training for engineering prosthetics. “My uncle is a neurologist and he bought a MindWave Mobile headset for me to play around with, to see if I could do anything interesting with it,” he says.

The headset works using EEG technology, which measures the electrical impulses produced by neurons in the brain. It’s been used for decades by doctors as a way of diagnosing epilepsy, but today it’s widely marketed as being able to read brain signals that allow users to play games without lifting a finger.

Around the time he received the headset, Nathan heard about a distant cousin in India who had lost both of her arms in an explosion. “When I learned about her injuries and I learned about the prosthetics she had received, I thought that I could build better ones,” he explains.

Though there are many cutting-edge prosthetics already on the market, from hands that let their wearer feel the texture of objects, to those that can see for themselves, most cost upwards of US$30,000 (£21,420).

Armed with his gaming headset and a $30 (£21) micro-controller ­– a device that can be programmed and then connected to other devices, such as a television – Nathan set about making a prosthetic arm that would be available to everyone.

Other than the micro-controller and the headset, the device was made entirely from materials from Nathan’s local electronics store

“The way it works is that it uses an EEG headset that is connected by Bluetooth to a micro-controller. The headset is able to read your brainwaves and based on the signals it receives from the brain, it can send that data via Bluetooth to the arm, which can control its movements,” he explains.

Other than the micro-controller and the headset, the device was made entirely from materials from Nathan’s local electronics store. “The schematics for it are all online, the programs for it are all online and you should ideally be able to program one yourself with off-the-shelf components,” he says. The “Arduino prosthesis” has won numerous awards, including prizes from the 2013 National microMedic Contest and the 2014 Bluetooth Breakthrough Awards. 

Other inventors have started even younger. Though he’s now 18, Adeeb Al Balooshi, from the United Arab Emirates, was just nine when he invented a waterproof prosthetic foot.

His father had polio as a child, and consequently his right leg didn’t grow as much as his left. Al Balooshi was first driven to invent while waiting for his father in the sea. He knew his father loved swimming, but it took him a long time to join his son, because he had to unstrap and remove his prosthetic first – a laborious process.

Al Balooshi set to work inventing a prosthetic foot that was lightweight and waterproof, so his father would never have to remove it at the beach again. The previous version was made from metal rods and leather, but the young inventor upgraded this to one made of graphene, a super-light, super-strong wonder material made of carbon. 

This new foot doesn’t have straps and is powered by hydraulics, much like a cutting-edge hand developed a few years earlier by a team of university-educated, adult researchers.

With the success of his father’s prosthetic foot, Al Balooshi went on to invent a cleaning robot for his mother and a seatbelt with a heart rate monitor inside, that can wirelessly beam health alerts to emergency services. Today he holds seven patents – and by a more youthful measure of success has over 36,000 Instagram followers.

Doherty decided to design a glove that could detect sign language using motion sensors and then convert it into speech

Then there’s Emma Doherty, a 15-year old from Greater Manchester in the UK who is developing the Speaking Signs device. This prosthetic isn’t for amputees, but for people with hearing loss.

It started two years ago. “I read an article where I saw how deaf people were struggling to interact with society because they were restricted to a certain number of people who understood sign language, and I was very interested to find a way around that,” she says.

Doherty decided to design a glove that could detect sign language using motion sensors and then convert it into speech. It was inspired by the singer Imogen Heap, who has invented gloves to turn gestures into music. “The deaf person wouldn’t be able to hear the response, so a microphone would be able to listen instead and note it down, sort of like how on an iPhone you can dictate to it. Then the response would be displayed on a screen on the glove,” she says.

Though it’s currently in the prototyping stage, Doherty’s glove has already attracted the attention of those it was designed to help. “Once it got out there and people heard about it, I started getting emails from people saying ‘How much do you need, how much are they, because my son is really struggling to interact with his friends, or with people in his class’,” she says.

Last year, Doherty’s idea won the UK’s Big Bang Fair, a prize for young inventors, and has attracted funding to continue its development from a software company based in Cambridge. Eventually, she hopes the Speaking Signs device will allow people with hearing difficulties to have conversations with any one of the seven billion people on our planet.

The field of prosthetics improved massively over the 20th Century. It seems there are a number of young inventors who want to ensure that innovation continues well into the 21st.

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