基于稳态视觉诱发电位的字符输入系统研究

Study on steady state visual evoked potential character input system

设计了一种基于稳态视觉诱发电位的实时脑-机接口系统,用于控制字符输入。系统以单片机和LED灯组成的视觉刺激器为稳态视觉诱发电位的刺激源,利用中科新拓NT9200系列脑电放大器对采集的脑电信号进行逐级放大,并采用滤波器进行滤波,之后通过USB数据线上传给计算机;在Lab VIEW平台上对不同频率刺激下产生的脑电信号进行实时处理,产生脑-机接口控制命令,实现字符输入。实验证实,该系统具有良好的可行性和可靠性,具有较高的应用价值。

Brain-computer interface（BCI） is a control system that utilizes electroencephalogram（EEG） to let people communicate with computers or other devices. The main point of this paper is a real-time BCT system based on the SSVEP which is used to control the character input. The system, with a visual stimulator consisting of a micro-controller and LED light as its stimulus source of SSVEP and using NT9200 series EEG amplifier to magnify and filter the collected EEG step by step to transmit it to computer through USB cable, processes the EEG generated under the stimulus of different frequencies on the Lab VIEW platform to create BCI controlling orders to input characters. The system is quite feasible and reliable and has a relatively higher application value.