Design Of Human Body Surface Electromyography Signal Acquisition And Processing System

Surface electromyography(SEMG)signal plays an important role in medical diagnosis,sports research,rehabilitation training and other industries.Therefore,higher requirements are placed on the acquisition and processing of SEMG signal.Interference and noise filtering are the main aspects of the research.However,at present,most of the acquisition circuits in china are composed of multi-block amplifiers that are configured with peripheral circuits.The degree of system integration is low,and the noise immunity is poor.Therefore,in this paper,I design a system of SEMG acquisition and processing,which has the characteristic of low noise.The typical characteristics of SEMG signals and the main sources of interference are described in this paper.Based on this,the design requirements and overall design of the system are proposed.The whole design scheme is divided into the design of acquisition device on the lower computer and the signal processing and analysis of LABVIEW on the upper computer.In the lower computer,to reduce the noise of the acquisition circuit,a circuit of hardware acquisition is proposed innovatively in this paper.The circuit is composed of two highly integrated,low-noise instrumentation amplifiers AD8233 and AD8422,which are configured with external resistors and capacitors.And the acquired signals are converted into digital signals and transmitted through the serial port by ATmega2560 microcontroller.After the actual measurement of hardware circuit,the acquisition circuit operates stably,and the performance indicators of acquired signals meet typical characteristics of SEMG.In the upper computer,the paper adopts LABVIEW to design SEMG acquisition and processing system,which can realize the waveform display,storage and playback of signals,and further filter ECG interference,50 Hz power frequency signals and other noise signals and make corresponding analysis of signals finally.Through the actual measurement of upper computer,the system basically meets the design requirements and can achieve the filtering function effectively.