A group of Nelson Mandela University engineering students, academics and their University of KwaZulu-Natal counterparts have built a robotic prosthetic to help amputees perform day-to-day functions.
The group presented the invention at the 2020 Global Cybathlon hosted virtually by Switzerland on the 13th & 14th of November 2020.
The members of the Touch Hand team were the only participants from Africa. The members of the team were NMU students; Sthuthi Varghese, Zahid Imran, Daniel Trask and Jode Fourie. They partnered with UKZN professor Riaan Stopforth and other contributors to create their prosthetic hand.
Cybathlon is a multi-sport event, that allows people with physical disabilities compete against each other to complete everyday tasks. They are able to do this using newly developed and adapted state-of-the-art technical assistance systems.
The Touch Hand team’s battery-operated prosthesis is able to imitate natural hand function, allowing the user to practise hand grips by picking up and placing items. Their technology used electromyography (EMG) signals from a person’s arm muscles to control the prosthetic’s movements.
At the Cybathlon there were 24 predetermined tasks across six stations. The African team had to compete against teams from other countries to complete these tasks using the Touch Hand-Socket prosthetic. The team finished 11th out of 13 competitors in their section.
NMU student Sthuthi Varghese said that the competition was quite tough because teams had to perform a lot of task in different stations, when discussing the tasks he said “It’s something that would be hard even for someone with a functioning [natural] hand but we’re very happy with our performance, especially because we were competing against international teams who are mostly in the private sector.”
The team noted that competition gave them the opportunity to identify where they could improve their prosthetic. They said they noticed that many of their competitors prosthetics were similar to theirs in design. However, competitors prosthetics had less motors allowing them to perform better and faster. They also noticed that many other prosthetics were smaller than theirs and therefore were able to perform some of the finer tasks better.
The team’s operator of the prosthetic hand was Port Elizabeth’s Lungile Dick. Before the Cybathlon they consulted with Livingstone Hospital’s Dr Bryan Theunissen to develop and test the limb on Dick, who lost his hand in an accident.
The prosthetic device was designed to be attached to Dick’s forearm where his natural hand would start using a 3D printed socket that covers, and keeps his forearm stable.
The hand picks up signals from Dick’s forearm to perform functions under his guidance. He is able to close the prosthetic hand into a fist, open it or move just the fingers.
Dr Theunissen advised the team that genrally, there is a stronger focus on lower-limb prosthetics as most upper-limb amputees don’t use their prostheses. This is not only because the prostheses are heavy, but also due to the fact that upper-limb amputees are currently not well served.
Most receive prosthetics with old 1970s technology or a cosmetic form that does not function in any way. It is due to this poor functionality that those who do have upper-limb prosthetic’s tended to abandon their prostheses. Knowing this the team’s primary aims was to create a light and safe prosthesis that is easy to use and walk around with.
Akhani 3D’s Lynton Dent said: “As an industry partner, we’re looking to localise the knowledge [of] technology and through linking with students and these projects we are achieving in terms [of] getting experts that can take this knowledge into industries and utilising it.”
The team partnered with Rapid 3D, 3D printer suppliers and consultants, to optimise their design of the 3D printed socket their prosthetic device attaches too and with 3D print service providers, Akhani 3D to 3D print the prosthetic.
