Brain-Computer Interface And Its Application In Robot Control

Brain-Computer Interface (BCI) is a new interactive system. BCI is developing very fast and is increasingly being applied in many fields in the past decade. Rehabilitation medical field is an important application field of BCI. BCI technology provides a "third hand" for the people suffering from serious impaired motion control. With the help of BCI system, people can control wheelchair or robot to help them with their mind. So BCI will make their daily life easier and will improve the quality of life.EEG signals collectted from the forehead region is focused on. First of all, DEAP EEG database is analyzed simply to prove that the forehead EEG signals (Fpl/Fp2) are able to classify emotions. Subsequently, experimental system based on MindWave Mobile is built for emotion recognition. Valence-Arousal model is used for emotion evaluation and short video is used to evoke specific emotion in the experiment. At last, the experimental result is evaluated according to self-assessment data from the subjects.Frequency-domain and time-domain characteristics are extracted from raw EEG data. Support vector machine (SVM) classification algorithm is then used for emotion classification. Two groups are selected:Whole and Indivdual, while two pairs of emotions are chosed:Happy-Sad and Excited-sleepy. In addition, the classification accuracy created by the difference between length of time units is analysed. The results show that emotion classification accuracy is 78% when using all the data. While the individual emotion classification accuracy is up to 91%.An online robot control system based on BCI technology is set up. Through this system people can control a 4-DOF robot by changing their own attention state. In this system MindWave Mobile is used to acquire EEG signal and the EEG data is sent to PC via Bluetooth. Software of upper computer is developed with MFC, which connect with lower computer via serial communication. In lower computer, STM32F103 is the core controller, and it generates four PWM wave and captures four encoder signals to guarantee accurate control of the 4-DOF manipulator. Motor drive circuit is built by LMD18200 with PWM control mode. The system has many advantages, because it is flexible, convenient, real-time, interesting and so on.