Wits students’ robotic hand
A team of Wits University engineering students are developing a game-changing fully functional yet affordable prosthetic hand
KIDS are curious creatures – they want to know how this works and what that means and why, why, why. And this guy was no exception – although from early on it was clear he was next-level in the inquisitive department.
Exactly how did the TV work, he wanted to know? What was the chemical composition of the wiper fluid in his dad’s car? And why didn’t it freeze in countries where it snowed a lot?
His parents, often at a loss, tried their best to answer him – and they’re no fools. His mom is a nurse and his dad a gastroenterologist, so they have a fair amount of knowledge between them.
But their young son wanted to know everything and the sooner he could figure things out for himself the better for everyone, they reasoned.
Today Abdul-Khaaliq Mohamed’s mind is as curious and active as ever – and he’s using it in a rather amazing way.
He’s leading a team at Wits University in Johannesburg who are developing a prosthetic hand that works with electrochemical signals from the brain. Their hand is sensitive and nimble enough to hold all sorts of objects, including a pen and a marble.
It requires no surgery to be fitted and costs a fraction of what something similar would cost elsewhere in the world.
The hand, which is still in the planning phase, could give amputees a new lease of life.
Artificial hands can be cumbersome, heavy, difficult to operate and cripplingly expensive. This one, the 32-year-old boffin says, is none of those things.
IT COMES as no surprise to learn Abdul-Khaaliq has an impressive CV. He has a degree in information engineering and a master’s degree in biomedical and control engineering. He’s worked as a software developer for Nokia Siemens Networks, a business analyst for Nedbank and an engineering consultant for an electrical industry consultancy.
The idea of controlling a prosthetic hand using signals from the brain started to take hold in 2008 while he was doing his master’s degree.
“I investigated whether it’s possible to discriminate between five different hand movements just by looking at the brain
signals. That analysis would be used to control a device such as the prosthetic hand,” he says.
In 2013 he became a lecturer in the department of electrical and information engineering at Wits and set out to build the hand.
Over the past four years the project has been part of the coursework for final-year electrical and information engineering students, which has allowed it to grow under Abdul-Khaaliq’s supervision.
“Most of the students are passionate about the project itself and they’re all keen to add on extra functionality, bring their own flare to it and suggest a lot of ideas.
“So they’ve all put in a lot of work and effort. They’ve been instrumental in getting the project to where it is now.”
Abdul-Khaaliq thanks his anthropologist wife, Raheemah Boomberg (26), and their young son, Abdul-Haadee (16 months), for supporting him throughout his journey.
“My son is very good at exploring and learning, and making me laugh,” he adds.
Exploring and learning – sounds like a chip off the old block!
HOW DOES THE HAND WORK?
Abdul-Khaaliq’s prosthetic hand is fully detachable and works with sensors that detect electrochemical signals from the arm muscles.
With a flex of the bicep the fingers of the prosthetic move, detecting the body’s electrochemical signals.
“The brain will transmit an electrical control signal through the nerves into the muscles and that will cause the muscles to move,” Abdul-Khaaliq explains. “You can pick up those electrical signals either directly from the brain or from the muscles.”
WHAT WILL IT COST?
A robotic hand like the one AbdulKhaaliq and his team are working on would go for around R500 000 in First World countries. “But how many people can afford that?” he says.
“Our hand costs about R2 000 the way it is now. It will change as we go along – we have to change and polish things up.
“So I would imagine the cost might go up, but I’ve always emphasised the cost needs to be as low as possible. As long as we keep it within an affordable bracket, I think we’ll be good.”
The hand is assembled in the lab with commercially available parts designed by Abdul-Khaaliq and the team, then printed using a 3D printer.
“One of the main reasons the cost is low is because we have budgeting constraints at the school,” he says.
“And the hand has to be kept affordable so the average person in South Africa who’s had an amputation can strive to get one.”
Their hand should make life for amputees much easier, he adds.
“Amputees often struggle because their prosthetic hands don’t fit properly or are too bulky or heavy. Current prosthetics have limited functionality, so a hand can’t always grip properly.
“For R30 000 you can’t even get a robotic hand. You’d get a mechanical hand that you’ve got to bend at the elbow in order for it to grip,” he says. Abdul-Khaaliq hopes to complete the project in the next three years.
WHAT’S NEXT FOR THE BOFFIN?
His next ambition is to create an exoskeleton with the technology he’s using on the hand and he hopes to start this project as early as next year.
“The exoskeleton would be for people who are paralysed, who have spinal cord injuries and don’t have the use of a hand anymore, or have limited use of their hands.
“In these cases you can’t cut off their hand and put on a prosthetic one. You’d have to have some sort of exoskeleton surface system that would be able to pick up what the person is trying to do and strengthen those movements or enable the hand to move.”