采用阵列式电极,通过空间滤波方法可提高表面肌电信号的MUAP分辨能力。本文实现的阵列式表面肌电信号采集仪由表面肌电电极阵列、信号调理电路和数据采集部分构成。表面肌电电极阵列实现了镀金圆盘式和弹簧探针式两种类型,信号调理电路对电极上的肌电信号进行放大和滤波,数据采集部分将调理后的信号转换成数据并进行显示和存储。电极阵列和前级信号调理电路集成在一起,有效的降低了微弱信号通过导线传输所引入的干扰。通过实验,验证了这种阵列式表面肌电采集仪在研究肌肉中动作电位传播和利用空间滤波提高MUAP分辨力的可行性,并证实了镀金圆盘式电极在降低噪声方面、弹簧探针式电极在缩短MUAP时长方面的优势。
The discrimination of MUAP from surface Electromyogram (sEMG) can be improved by using electrodes array and space filtering method. According to this principle, an array acquisition instrument for sEMG was developed in this paper, containing sEMG electrodes array, signal conditioning circuits and a data acquisition part. Gold plated disk shaped electrodes and spring probe electrodes built up two different kinds of sEMG electrode array; The conditioning circuit amplifies and filters the signal form electrode array; The data acquisition part converted the conditioned signal to digital for display and storage. The electrode array is integrated with the first-stage conditioning circuit, in order to prevent interferences of weak signal transmission through wires. It is proved that the array acquisition instrument can be used in the research of action potential transmission in muscles, and it can improve the discrimination of MUAP by using space filtering method. It is also proved that the gold plated disk shaped electrodes work better in noise reduction and the spring probe electrodes work better in reducing the MUAP duration.