基于光电容积描记法的多路肌肉收缩传感系统

Multichannel Muscle Contraction Sensing System Based on PPG

为了更好地研究肌肉的收缩运动,介绍了光电容积描记法(PPG)探测肌肉收缩运动的原理,设计了可以同时检测4路信号的反射式光电肌肉收缩传感系统。利用可编程恒流源驱动红外LED,将红外光照射到肌肉组织中,透射出肌肉的光被另外的红外探测电路检测到,并被转换为电信号。在单片机的控制下,4路检测到的电信号通过模拟多路开关实现分时导通,随后分别进行低通滤波和AD采样,最后将得到的4路数据通过蓝牙模块传送到上位机电脑端进行后继处理。电路实现了4路信号的同步探测功能,系统测量准确,性能可靠,具有一定的实用价值。

In order to better study muscle contraction,we introduce the principle of detecting muscle contraction using Photoplethysmography(PPG).An IR muscle contraction sensing system in reflection mode is designed,the system can detect signals from 4 channels at the same time.An IR LED driven by a programmable current source emits IR light into the muscle tissue.The optical detection circuit translates the tiny output light from the muscle into electronic signal.Under the control of MCU,the 4 channels of detected signals are sent to an analog multiplexer,each channel is turned on at different times,and then executed lowpass filtering and AD converting separately.Finally the data of the4 channels is sent to a upper computer through Bluetooth module for further processing.This system have the capability of detecting signals from 4 channels simultaneously,and it is accurate,reliable and useful.