A Hybrid BCI Based on SSVEP and EOG for Robotic Arm Control.

Yuanlu Zhu,Ying Li,Jinling Lu,Pengcheng Li

doi:10.3389/fnbot.2020.583641

Abstract

Brain-computer interface (BCI) for robotic arm control has been studied to improve the life quality of people with severe motor disabilities. There are still challenges for robotic arm control in accomplishing a complex task with a series of actions. An efficient switch and a timely cancel command are helpful in the application of robotic arm. Based on the above, we proposed an asynchronous hybrid BCI in this study. The basic control of a robotic arm with six degrees of freedom was a steady-state visual evoked potential (SSVEP) based BCI with fifteen target classes. We designed an EOG-based switch which used a triple blink to either activate or deactivate the flash of SSVEP-based BCI. Stopping flash in the idle state can help to reduce visual fatigue and false activation rate (FAR). Additionally, users were allowed to cancel the current command simply by a wink in the feedback phase to avoid executing the incorrect command. Fifteen subjects participated and completed the experiments. The cue-based experiment obtained an average accuracy of 92.09%, and the information transfer rates (ITR) resulted in 35.98 bits/min. The mean FAR of the switch was 0.01/min. Furthermore, all subjects succeeded in asynchronously operating the robotic arm to grasp, lift, and move a target object from the initial position to a specific location. The results indicated the feasibility of the combination of EOG and SSVEP signals and the flexibility of EOG signal in BCI to complete a complicated task of robotic arm control.

Highlights

Brain-computer interfaces (BCIs) are designed as a bridge to construct direct communication between the brain and external devices without relying on normal peripheral nerves and muscle tissue (Wolpaw et al, 2000)
As for the cue-based experiment, the classification accuracy and information transfer rates (ITR) were calculated to evaluate the performance of the SSVEPbased BCI
The false activation rate (FAR) which meant the rate of false triggering (Wang et al, 2014) was used to assess the Triple blink FAR Wink true positive rate (TPR) (%) Wink false positive rate (FPR) (%) Subject

Summary

Introduction

Brain-computer interfaces (BCIs) are designed as a bridge to construct direct communication between the brain and external devices without relying on normal peripheral nerves and muscle tissue (Wolpaw et al, 2000). BCIs aim to provide people with severe motor disabilities an alternative to communicate and control external devices. Many studies have attempted to realize BCI for robotic arm control to improve the life quality of people with motor impairment (Pfurtscheller et al, 2010b; Gao et al, 2017; Khan and Hong, 2017). Several types of physiological activation are usually chosen to generate the output commands of the EEG-based BCI, such as motor imagery (MI) (Wolpaw et al, 1991), P300 (Farwell and Donchin, 1988), and steady-state visual evoked potential

Methods

Results

Discussion

Conclusion