Wearable robots are nothing new to science fiction and comic book heroes, and have been gaining popularity in the real world as a means to extend human physical capabilities.
A new possible application of robotic exoskeletons has now come to light, thanks to a recent study from the University of Chicago – these devices may hold the key for patients hoping to regain the use of a paralyzed limb.
If there’s anything cooler than wearable robots, it’s moving things with your mind, and that’s exactly what these robots are designed to facilitate. In their study, published last month in The Journal of Neuroscience, a research team led by Nicholas Hatsopoulos set up a system that translated brain wave activity of monkeys into the motion of a cursor on a screen, allowing a monkey to control the movement of the cursor using only its thoughts.
A robotic sleeve was fitted around the monkey’s arm, which moved the arm along with the motion of the cursor. The researchers found that the robotic sleeve, which gave the monkey sensory feedback about how the cursor was moving, greatly improved the ability of the monkey to mentally manipulate the cursor.
The idea for the use of the robot came from what is known about how the brain usually controls movement of the body. Imagine moving your arm: first, your brain tells your arm where to go. As your arm moves, nerves in your arm relay information back to the brain about the arm’s position. This allows the brain to make a new informed decision about where to move the arm next. If the arm is paralyzed due to illness or injury, the brain can’t control the movement of the arm, but can often still receive information about the arm’s position (depending on the extent of the damage).
This is where the wearable robots come in – the robot does the job of moving the arm in response to instructions from the brain, and the arm keeps the brain updated about its motion. In the study, this sensory feedback, so-called proprioception, allowed the monkeys to more quickly and more directly move the cursor on the screen towards targets compared to the case where the arm remained stationary.
Previous instances of devices that can be controlled by brain activity have relied on visual feedback alone, where the patient must watch the movement of the device. The use of the robotic arm to add proprioceptive feedback more closely mimics motor control in healthy individuals.
The results presented by Hatsopoulos and his team are promising for patients with a paralyzed limb – devices with proprioception capabilities would offer a patient not only improved control, but also the ability to move the limb while looking away or with closed eyes.
Are robotic exoskeletons in the future for restoring the use of paralyzed limbs? Only time will tell, but it’s safe to say that robot suits aren’t just for Ironman anymore.
See the press release from the University of Chicago here: http://www.uchospitals.edu/news/2010/20101214-robot-arm.html
Want to learn more about devices that can be controlled by the brain? Watch this video of researchers at the University of Pittsburgh explaining how monkeys mentally control a robotic arm!
About the Author
Minna is a Ph.D. candidate in Materials Science and Engineering at Northwestern University
In her current research, Minna is working to solve mysteries about how organisms form biological minerals (such as bones and shells) by looking at them in new ways using X-ray microscopes at the Advanced Photon Source. Most of her work involves a type of green algae that she hopes to use for cleanup of radioactive waste, but she’s also had the opportunity to work with other fun organisms such as bees, sea urchins, mussels, and clams (although she definitely could have done without the bees).