On June 12th, the FIFA 2014 World Cup in Brazil will be kicked off by a paralyzed person using a highly innovative brain-controlled robotic exoskeleton. This feat is being carried out as a demonstration of the current state-of-the art in assisted mobility technology, as the researchers involved – part of the "Walk Again Project" – work toward refining their invention.
Early prototypes of robotic exoskeletons are pushing the boundaries of technology to allow paralyzed people to walk again, even allowing people to control the device with their thoughts alone. However, these exoskeletons are often very cumbersome and give the user poor feedback, which limits both range and precision of movement.
The Walk Again Project, an international collaboration of over 100 scientists across the globe, is developing a smart, modular and lightweight exoskeleton that can be precisely controlled using the power of thought alone.
"It's a key societal endeavor that we want to accomplish, to enable someone to walk again after they have been paralyzed for many years," says Prof. Gordon Cheng at Technische Universität München, one of the main contributors to the project.
In the device a set of external, non-invasive electrodes read the patient's brain signals and attempt to decode his or her intentions. The commands are then used to move the exoskeleton, which is laden with a dense network of sensors that provide immediate feedback to the patient.
The sensors are embedded in what the researchers call CellulARSkin, a surface consisting of flat, hexagonal cells in a honeycomb structure. Each cell is approximately one inch in diameter and contains a low-power microprocessor and accelerometer, as well as sensors for proximity, pressure, vibration and temperature.
The artificial skin in being used in two ways: as a part the exoskeleton, including in the soles of the feet, it is used to measure proximity to the ground and then send signals for tactile feedback against the patient's arms; and secondly, wrapped around the patient's body, it is used to monitor the patient's vitals, looking for possible signs of distress.
The large number of cells within a single exoskeleton make the system highly redundant and therefore more reliable. Also, the cells can be manufactured from off-the-shelf hardware, which cuts down costs significantly.
Eight Brazilian men and women between the ages of 20 and 40 who are paralyzed from the waist down have been training for months to use the exoskeleton, and soon one of them will be the one to kick off the next World Cup.
"This is one big milestone, a demonstration of what science can really do for somebody, but we still have a lot to do," says Cheng. "We should be able to make the exoskeleton cheaper, more agile, more diverse for the patient. I think we'll be able to invest another 10 years on this, and it's a worthy effort."