Research Of Multi-conductance And Multi-mode Transcranial Electrical Stimulation Device

With the rapid pace of life in modern society,more and more people are suffering from mental illness.In medicine,electrical stimulation is often used to treat depression,insomnia and other mental disorders.When the frequency and other parameters are set,the output waveform of the electrical stimulation will remain unchanged.Considering the strong adaptability of the human body,the human body will gradually adapt to this fixed stimulus if it takes a long period of constant electrical stimulation to the human body.In order to reduce the therapeutic effect,a multi-conductance and multi-mode transcranial electrical stimulation device was developed by using functional signals and EEG signals.The multi-conductance and multi-mode transcranial electrical stimulation device designed in this paper can output four channels function stimulation signals.Each stimulation signal can be adjusted separately.The device can also collect two channels EEG signals and convert them into two channels EEG stimulation signals.The device consists of two parts: hardware and software.The hardware mainly includes EEG conditioning circuit,electric stimulation conditioning circuit STM32F407 system circuit,FPGA control circuit and EEG A/D conversion ADS1298 circuit.The software part mainly includes STM32F407 logic program and GUI software application.The GUI application software is based on the windows operating system,and the input controls on the software interface choose the stimulation mode and parameters.The instruction is sent to STM32F407 module.STM32F407 module parses the received instruction and sends it to FPGA module via FSMC bus.If the function stimulation mode is selected,the FPGA module sends the parameters to the electrical stimulation conditioning circuit to output the function stimulus signal.If the EEG stimulation mode is selected,the FPGA module controls the ADS1298 circuit to collect the EEG signal and store it in the SDRAM chip.After the time of the acquisition arrives,the EEG signal stored in the SDRAM chip is read out.The experimental results show that the device can output the electrical stimulation signal with adjustable parameters and mode,and the performance of the device can meet the design requirements.In this paper,the significance of transcranial electrical stimulation equipment and its development at home and abroad are described,and the related theories and techniques of transcranial electrical stimulation equipment are studied.Then the overall design scheme of multi-conductance and multi-mode transcranial electrical stimulation equipment is proposed,and the detailed hardware design,software design and final test are given to verify the function of the system.