Research On Chinese Character Input Method On EEG Singal

Brain-computer interface(BCI)is a kind of external equipment that can rely on brain activity to operate,which does not rely on the normal output of the brain,namely peripheral nerves and muscle tissue,to achieve communication with the outside world.Combining current popular artificial intelligence technology,Brain-computer interfaces are gradually becoming the focus of research in brain science,and more and more research groups are involved in the research and design of braincomputer interfaces.At present,the main application scenarios of brain-computer interface are in exercise assistance or substitution,communication interaction,neurological function treatment or adjustment,etc.However,due to the impact of acquisition equipment and EEG classification accuracy,most brain-computer interface devices are still in the experiment In the room,there is no large-scale put into actual use.On the basis of consulting a large number of literatures,this article introduces the basic definition of brain-computer interface,common EEG patterns of brain-computer interface,and summarizes the current research status,application prospects and main challenges of brain-computer interface.It introduces the replication size,frequency range and generation mechanism of several common types of EEG patterns,and describes in detail the process of EEG processing and analysis.Through analysis and comparison of the advantages and disadvantages of several EEG modes,combined with their own brain-computer interface design needs,the SSVEP mode is proposed.Based on the previous theoretical research foundation and reference to other brain-computer interface research and design materials,a portable character input system based on steady-state visual stimuli was independently designed,which mainly includes EEG acquisition module,stimulus presentation interface and experimental paradigm method design.Introduce the design principles and specifications of the acquisition system circuit in detail,and use the designed equipment to conduct test experiments,record data,and perform offline processing and analysis of the data to verify the rationality and feasibility of the acquisition system.Conducting online experiments based on this system,try to compare the changes in the correct spelling of characters with different motor combinations,and aim to use the least number of electrodes to achieve a higher classification accuracy.On the basis of the above research,this article completed the character input system,realized the input of simple characters,the recognition rate of a single EEG signal is more than 80% and the recognition time of a single EEG signal is about 3.5 seconds,a good character input effect is achieved.