SSVEP-based BCI control for navigating a robot

Keywords
Loading...
Thumbnail Image
Issue Date
2013-12-31
Language
en
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Controlling devices without psychical contact is an important aspect of paralyzed people, operators who need to handle multiple controls and those missing limbs caused by an accident. Speech recognition can work for some, but is not efficient in noisy areas. BCI systems using imagined movement can overcome this, but it is tiring to keep a constant imagined state that is mentally clear enough for the system to detect. Steady-state visually evoked potentials (SSVEPs) are known to induce a clear signal for a BCI system to trigger external devices or mechanics. This way, someone can control a mobile device by merely looking at a particular target on the device. This research will answer the question of how BCI performance behaves over larger distances (>100 cm). More specific, we designed an experiment that would test how both the user-stimulus distance and orientation of the stimuli would affect SSVEP BCI performance. For this we used a Lego robot application to navigate a multiple-turn track. Performance rates during navigation varied between 59.0%-70.4% with large differences in completion times among participants. As our question remained unanswered, we conducted a second experiment with a focus on measuring the relation between user-stimulus distance and SSVEP BCI performance. Results show a relatively stable signal for non-target stimuli, while the target stimulus showed a decrease in frequency amplitude over distance. The majority of the obtained results shows a significant correlation between the distance, which is related to the visual angle, and the amplitude of the stimulated frequency. Keywords: BCI, brain-computer interface, SSVEP, steady-state visually evoked potential, LED, distance, visual angle, LEGO robot.
Description
Citation
Faculty
Faculteit der Sociale Wetenschappen