Studies On The Methods Of EEG Acquisition And Its Application In The Artificial Hands

Acquisition of EEG signals is the important branch of the Biomedical Engineering; it provides not only the essential data for basic research in study of brain and neural clinical diagnosis but also the motion information in major limb produced by brain. It can be obtained by means of signal processing. And the application of EEG would be found in many fields especially in Rehabilitation Engineering. So the research of acquisition system of EEG signals is of important significance. In the system of artificial hands based EEG, acquisition of EEG is of the important part.So far, the studies in EEG have been concentrated on providing an efficient way to communicate with the outer-world and recall some limb functions for individuals with severe motor defects. In the research of artificial hands controlled by EEG, finding that the EEG acquisition plays the key role in the artificial hands system. However, the acquisition of EEG is all through the difficult project because of the unique feature in EEG itself and environments. In order to control the artificial hands, the EEG should be true and steady and the system should be of portable.In this paper, the conception and characteristic of EEG signals were introduced, and then the signal conditioning and data acquisition was set on two different boards, which reduced the interference between digital signals and analog signals. The signal acquisition system mainly deal with the acquisition of EEG, the conditioning, amplifying and A/D converting which are imposed on the signals, only after this can the signals enter the computer. The main design work as follow: the former disposal circuits were designed, and the circuit possesses very high input resistance, common-mode rejection and voltage gain; the design of AT89C2051 microprocessor system which can perform the A/D conversion from EEG signal to digital data; finished the serial communication from Microprocessor to PCs with the development environment LabVIEW; design the interface of EEG displaying which can do the simple EEG processing. At last, a kind of application of EEG in artificial hands system was put forward.