Researchers in Graz control robots with their thoughts

The team at TU Graz made a significant breakthrough in neuroprosthetics using thoughts and a non-neurochip method to control robotic arms

Yesterday, the Graz University of Technology (TU Graz) reported a major breakthrough in neurotechnology – for the first time test subjects were able to non-invasively control a robotic arm just by thinking about it. The experiments were done in real-time and the subjects did not use implants or neural chips, but a simple EEG cap, measuring their brain activity.

This research holds great potential for paraplegics precisely because it is non-invasive. The neuroprosthetics uses a technology called Brain-Computer Interfaces (BICs) to measure brain activity and concert that to electrical signals.

Moving things with the mind

According to Gernot Müller-Putz, head of the Institute of Neurotechnology in TU Graz explained that the mere idea of movement triggers a measurable change in brain activity. What researchers needed to do was pinpoint the specific change and relate that to a specific movement.

It also turns out that hand-eye coordination is key to fluid precise motions. Müller-Putz was quoted in a press release explaining that "it is important that users are allowed to use their eyes to follow the trajectory of the robotic arm.” The visual information helps to capture the intention to move. The interfering signals from the eye itself, however, have to be calculated from the electrical activity.

The BIC also has a built-in error detection system. Essentially, the interface measures, recognises and corrects errors based on brain activity. Once it has detected an error it either corrects the motion or goes back into the starting position.

The test subjects, participating in the trials were paraplegic and according to Müller-Putz, they were able to replicate the successful trial runs several times.

Feeling the movement

The researchers went a step further and implemented a kinetic feedback system to go with everything else. What this means is that a subject can feel the movement of the robotic arm as if it were attached to their body. This is done with the help of vibration transmitters, stuck to the skin on the shoulder blade. Theoretically, this means that it is possible for someone who is completely disabled to feel movement again.

Furthermore, Müller-Putz and the team have decided to set the bar for the future even higher, as one of their distant goals is to find applications for the technology in the neck area. For now, however, their immediate pursuit is to decode brain activity even better and perfect the movement of the arm.