Ryerson biomedical engineering students Michal Prywata and Thiago Caires’ prosthetic arm
Biomedical engineering students at Ryerson University, Toronto, Canada, have invented a prosthetic arm controlled by brain signals.
The Artificial Muscle-Operated (AMO) Arm, developed by third-year student Thiago Caires and second-year student Michal Prywata, uses compressed air as its main source of power. The device employs signals in the brain that are detected by a head-set worn by the user-for example, the thought “up”-that is sent wirelessly to a miniature computer in the arm. The computer then compares the signal to others in a database. The resulting information is sent to the pneumatic system, which in turn activates the arm to create the appropriate movement. The system uses compressed air from a small, refillable tank in the user’s pocket to simulate the expansion and contraction of real muscles. The AMO Arm can currently move up, down, left, and right, as well as open and close.
The artificial muscle system created by Caires and Prywata is a first in the field of prosthetics, according to a university press release, and the students continue to perfect their system. For example, they are at work on a design to fit the tank into the arm itself and to get each finger on the AMO Arm to move individually.
“Independent finger movements require many more sensors,” Caires said. “For example, while not impossible, it’s still quite difficult to grab a key and unlock a door.”
Since the AMO Arm does not include microelectronics and motors or require surgery for its application, it’s less costly to produce than other functional prosthetic arms, and requires a short period of adjustment.
“In just ten minutes of practicing, a person can pick up the mind-control aspect of the technology,” Prywata said. Moreover, he added, the AMO Arm will not only benefit amputees, but could also be used as an assistive device on wheelchairs, enabling users to reach things with greater ease. The technology could also be used by the military to facilitate remote operations and in situations requiring robotics.
It took a year for the students to develop the software program for the AMO Arm while the actual prototype was created during a marathon 72-hour design session.
The AMO Arm won first prize at the 2011 Ryerson Engineering Competition in January. The students took home first-place awards for innovative design and social awareness at the Ontario Engineering Competition in February, and in the Canadian Engineering Competition in March, the device placed second in the innovative design category.
In the future, the pair would also like the AMO Arm to sense different materials, such as an egg versus a full bottle of water, and adjust the force used proportionately. The students also have plans to develop an adaptive system, one that will progressively “learn” from a user’s movements for more seamless outcomes.
Prywata and Caires have formed their own company, Bionik Laboratories, Ontario, Canada, and are currently seeking three patents for the AMO Arm and their other technologies for commercialization purposes.
Adapted from source material provided by Ryerson University.
