A team of researchers from Carnegie Mellon University, in collaboration with 
the University of Minnesota, has made a breakthrough in the field of 
noninvasive robotic device control. Using a noninvasive brain-computer 
interface (BCI), researchers have developed the first-ever successful 
mind-controlled robotic arm exhibiting the ability to continuously track and 
follow a computer cursor.

Being able to noninvasively control robotic devices using only thoughts will 
have broad applications, in particular benefiting the lives of paralyzed 
patients and those with movement disorders.

BCIs have been shown to achieve good performance for controlling robotic 
devices using only the signals sensed from brain implants. When robotic devices 
can be controlled with high precision, they can be used to complete a variety 
of daily tasks. Until now, however, BCIs successful in controlling robotic arms 
have used invasive brain implants. These implants require a substantial amount 
of medical and surgical expertise to correctly install and operate, not to 
mention cost and potential risks to subjects, and as such, their use has been 
limited to just a few clinical cases.

A grand challenge in BCI research is to develop less invasive or even totally 
noninvasive technology that would allow paralyzed patients to control their 
environment or robotic limbs using their own "thoughts." Such noninvasive BCI 
technology, if successful, would bring such much needed technology to numerous 
patients and even potentially to the general population. 

However, BCIs that use noninvasive external sensing, rather than brain 
implants, receive "dirtier" signals, leading to current lower resolution and 
less precise control. Thus, when using only the brain to control a robotic arm, 
a noninvasive BCI doesn't stand up to using implanted devices. Despite this, 
BCI researchers have forged ahead, their eye on the prize of a less- or 
non-invasive technology that could help patients everywhere on a daily basis. 

Bin He, Trustee Professor and Department Head of Biomedical Engineering at 
Carnegie Mellon University, is achieving that goal, one key discovery at a time.

"There have been major advances in mind controlled robotic devices using brain 
implants. It's excellent science," says He. "But noninvasive is the ultimate 
goal. Advances in neural decoding and the practical utility of noninvasive 
robotic arm control will have major implications on the eventual development of 
noninvasive neurorobotics."

Using novel sensing and machine learning techniques, He and his lab have been 
able to access signals deep within the brain, achieving a high resolution of 
control over a robotic arm. With noninvasive neuroimaging and a novel 
continuous pursuit paradigm, He is overcoming the noisy EEG signals leading to 
significantly improve EEG-based neural decoding, and facilitating real-time 
continuous 2D robotic device control.

Using a noninvasive BCI to control a robotic arm that's tracking a cursor on a 
computer screen, for the first time ever, He has shown in human subjects that a 
robotic arm can now follow the cursor continuously. Whereas robotic arms 
controlled by humans noninvasively had previously followed a moving cursor in 
jerky, discrete motions--as though the robotic arm was trying to "catch up" to 
the brain's commands--now, the arm follows the cursor in a smooth, continuous 
path.

In a paper published in Science Robotics, the team established a new framework 
that addresses and improves upon the "brain" and "computer" components of BCI 
by increasing user engagement and training, as well as spatial resolution of 
noninvasive neural data through EEG source imaging.

The paper, "Noninvasive neuroimaging enhances continuous neural tracking for 
robotic device control," shows that the team's unique approach to solving this 
problem not enhanced BCI learning by nearly 60% for traditional center-out 
tasks, it also enhanced continuous tracking of a computer cursor by over 500%.

The technology also has applications that could help a variety of people, by 
offering safe, noninvasive "mind control" of devices that can allow people to 
interact with and control their environments. The technology has, to date, been 
tested in 68 able-bodied human subjects (up to 10 sessions for each subject), 
including virtual device control and controlling of a robotic arm for 
continuous pursuit. The technology is directly applicable to patients, and the 
team plans to conduct clinical trials in the near future.

"Despite technical challenges using noninvasive signals, we are fully committed 
to bringing this safe and economic technology to people who can benefit from 
it," says He. "This work represents an important step in noninvasive 
brain-computer interfaces, a technology which someday may become a pervasive 
assistive technology aiding everyone, like smartphones."

This work was supported in part by the National Center for Complementary and 
Integrative Health, National Institute of Neurological Disorders and Stroke, 
National Institute of Biomedical Imaging and Bioengineering, and National 
Institute of Mental Health. 

About the College of Engineering: The College of Engineering at Carnegie Mellon 
University is a top-ranked engineering college that is known for our 
intentional focus on cross-disciplinary collaboration in research. The College 
is well-known for working on problems of both scientific and practical 
importance. Our "maker" culture is ingrained in all that we do, leading to 
novel approaches and transformative results. Our acclaimed faculty have a focus 
on innovation management and engineering to yield transformative results that 
will drive the intellectual and economic vitality of our community, nation and 
world. 

About Carnegie Mellon University: Carnegie Mellon (www.cmu.edu) is a private, 
internationally ranked university with programs in areas ranging from science, 
technology and business to public policy, the humanities and the arts. More 
than 13,000 students in the university's seven schools and colleges benefit 
from a small faculty-to-student ratio and an education characterized by its 
focus on creating and implementing solutions for real world problems, 
interdisciplinary collaboration and innovation. 

Contact: Emily Durham; 412-268-2406; edurham1@andrew.cmu.edu

SOURCE: Carnegie Mellon University College of Engineering