基于单片机的人体脉搏检测系统设计.doc

基于单片机的人体脉搏检测系统设计 摘要 脉搏波所呈现出来的形态、强度、速率和节律等方面的综合信息，能反映出人体心血管系统中许多生理疾病的血流特征。本文首先描述本设计的整体思路，然后介绍各个部分设计中的细节问题，最后提出一些完善本设计的改进意见。 THE DESIGN OF HUMAN PLUSE DETECTION SYSTEM BASED ON MCU ABSTRACT The shape, intensity, speed, and rhythm of pulse signals mostly reflect the physical and pathological characters of heart-blood system in human bodies. This topic is a design of body pulse measuring instrument. Because of the specificity of the pulse signal, the design must pay attention to achieve an accurate measurement.The point of this design is the simple and precise of the measurement.We need to measure the pulse of the human body in one minute,and to ensure that the error in less than 2 times..The whole system is center on single-chip microcomputer 89s51,using the signle-chip to achieve the system core function of counting pulse.In the front-end of the signal, we use piezoelectric ceramics to collect the signal of the human body pulse.And then,after after amplification of the AD620, shaping of the 555, filtering of the low-pass filter and other operations,the signal will be converted to the pulse signal with the same frequency,and this signal will be input to the single-ship.The single-ship will count to this.The method of counting is using the timer of the single-ship,and then use the cycle,get the frequency,by the frequency,we can get the number of the one-minute pulse. The final result of the count will display in the 1602 LCD screen.Although the performance of the piezoelectric ceramics is not very good,in the signal collection.it can’t do it very precise.But its price is very low,and after the signal conditioning circuit of the system,the signal can be quite satisfactory to achieve our objectives. At the beginning of the paper, the integral notion of the device design is brought out. Afterwards, the detail information of each part is narrated. At last part, some suggestions for improving the device are provided. Key words: Pulse measurement; piezoelectric ceramics;