Using an electroencephalogram cap, the new system allows users to move forwards, turn left and right, sit and stand simply by staring at one of five flickering LEDs.

Each of the five LEDs flickers at a different frequency, and when the user focusses their attention on a specific LED this frequency is reflected within the electroencephalogram readout. This signal is identified and used to control the exoskeleton.

A key problem has been separating these precise brain signals from those associated with other brain activity, and the highly artificial signals generated by the exoskeleton.

“Exoskeletons create lots of electrical ‘noise.’ The electroencephalogram (EEG) signal gets buried under all this noise – but our system is able to separate not only the EEG signal, but the frequency of the flickering LED within this signal,” said team member Dr Klaus-Robert Muller from TU Berlin and Korea University.

Although the team reports tests on healthy individuals, the system has the potential to aid sick or disabled people.

“People with amyotrophic lateral sclerosis or high spinal cord injuries face difficulties communicating or using their limbs. Decoding what they intend from their brain signals could offer means to communicate and walk again,” said Dr Muller, who is a co-author of a paper published in the Journal of Neural Engineering.

The control system could serve as a technically simple and feasible add-on to other devices, with EEG caps and hardware now emerging on the consumer market.

It only took volunteers a few minutes to be training how to operate the system.

Because of the flickering LEDs, they were carefully screened for epilepsy prior to taking part in the research.

Dr Muller and his colleagues are now working to reduce the ‘visual fatigue’ associated with longer-term users of such systems.