Brain-computer interface for robot control with eye artifacts for assistive applications.

Journal: Scientific reports
Published Date:

Abstract

Human-robot interaction is a rapidly developing field and robots have been taking more active roles in our daily lives. Patient care is one of the fields in which robots are becoming more present, especially for people with disabilities. People with neurodegenerative disorders might not consciously or voluntarily produce movements other than those involving the eyes or eyelids. In this context, Brain-Computer Interface (BCI) systems present an alternative way to communicate or interact with the external world. In order to improve the lives of people with disabilities, this paper presents a novel BCI to control an assistive robot with user's eye artifacts. In this study, eye artifacts that contaminate the electroencephalogram (EEG) signals are considered a valuable source of information thanks to their high signal-to-noise ratio and intentional generation. The proposed methodology detects eye artifacts from EEG signals through characteristic shapes that occur during the events. The lateral movements are distinguished by their ordered peak and valley formation and the opposite phase of the signals measured at F7 and F8 channels. This work, as far as the authors' knowledge, is the first method that used this behavior to detect lateral eye movements. For the blinks detection, a double-thresholding method is proposed by the authors to catch both weak blinks as well as regular ones, differentiating itself from the other algorithms in the literature that normally use only one threshold. Real-time detected events with their virtual time stamps are fed into a second algorithm, to further distinguish between double and quadruple blinks from single blinks occurrence frequency. After testing the algorithm offline and in realtime, the algorithm is implemented on the device. The created BCI was used to control an assistive robot through a graphical user interface. The validation experiments including 5 participants prove that the developed BCI is able to control the robot.

Authors

  • Kaan Karas
    Politecnico di Milano, Department of Mechanical Engineering, via La Masa 1, 20156, Milano, Italy.
  • Luca Pozzi
    Bioengineering Department, Politecnico di Milano, 20133, Milano, Italy.
  • Alessandra Pedrocchi
  • Francesco Braghin
    Mechanical Engineering Department, Politecnico di Milano, Via Giuseppe La Masa 1, 20156 Milan, Italy.
  • Loris Roveda
    Dalle Molle Institute for Artificial Intelligence, Università della Svizzera italiana/Scuola universitaria professionale della Svizzera italiana, Lugano, Switzerland.