单片机的脉搏测量仪的设计开题分析方案6Word文档下载推荐.docx

1、2018年 3 月11日开题报告内容与要求一、毕业设计论文）内容及研究意义价值）随着科技发展的不断提高，生命科学和信息科学的结合越来越紧密，出现了各种新颖的脉搏测量仪器，特别是电子脉搏仪的出现，使脉搏测量变得非常方便。 脉诊在我国已具有2600多年临床实践，是我国传统中医的精髓，但祖国传统医学采用“望、闻、问、切”的手段进行病情诊断，受人为的影响因素较大，测量精度不高。科技的创新，脉搏测试不再局限于传统的人工测试法或听诊器测试法，脉搏测量可利用电子仪器测量出精度更就的数据。 人体脉搏信号中包含丰富的生理信息，也逐渐引起了临床医生的很大兴趣，达到了方便、快捷、准确的测量脉搏的目的。随着电子测量技

2、术的迅速发展，现代电子测量仪器以极快的速度向数字化、自动化的方向发展。制成的脉搏测量仪器性能良好，结构简单，有较好的应用和推广价值。脉搏测量仪的设计，必须是通过采集人体脉搏变化引起的一些生物信号，然后把生物信号转化为物理信号，使得这些变化的物理信号能够表达人体的脉搏变化，最后要得出每分钟的脉搏次数，就需要通过相应的硬件电路及芯片来处理物理变化并存储脉搏次数。在硬件设计中一般的物理信号就是电压变化。本系统的组成包括传感器、信号处理、单片机电路、显示电路、键盘输入等部分。二、毕业设计论文）研究现状和发展趋势文献综述）随着科学技术的发展，脉搏测量技术也越来越先进，对脉搏的测量精度也越来越高，国内外先

3、后研制了不同类型的脉搏测量仪，脉搏测试不再局限于传统的人工测试法或听诊器测试法，脉搏测量可利用电子仪器测量出精度更就的数据。人体脉搏信号中包含丰富的生理信息，也逐渐引起了临床医生的很大兴趣，达到了方便、快捷、准确在测量脉搏的目的。而其中关键是对脉搏传感器的研究。起初用于体育测量的脉搏测试集中在对接触式传感器的研究，利用此类传感器所研制的指脉、耳脉等测量仪各有其优缺点。指脉测量比较方便、简单，但因为手指上的汗腺较多，指夹常年使用，污染可能会使测量灵敏度下降：耳脉测量比较干净，传感器使用环境污染少，容易维护。但因耳脉较弱，尤其是当季节变化时，所测信号受环境温度影响明显，造成测量结果不准确。过去在医

4、院临床监护和日常中老年保健中出现的日常监护仪器，如便携式电子血压计，可以完成脉搏的测量,但是这种便携式电子血压计利用微型气泵加压橡胶气囊，每次测量都需要一个加压和减压的过程，存在体积庞大、加减压过程会有不适、脉搏检测的精确度低等缺点。脉搏测量仪的发展主要向以下几个趋势发展：、强度（波幅、速率（波速和节律（周期等方面的综合信息，在很大程度上反映出人体心血管系统中许多生理病理的血流特征,因此对脉搏波采集和处理具有很高的医学价值和应用前景。但人体的生物信号多属于强噪声背景下的低频的弱信号, 脉搏波信号更是低频微弱的非电生理信号,因此必需经过放大和后级滤波以满足采集的要求。三、毕业设计论文）研究方案及

5、工作计划含工作重点与难点及拟采用的途径）本设计采用单片机AT89C51为控制核心，实现脉搏测量仪的基本测量功能。系统硬件框图如下图1所示：图1 脉搏测量仪硬件框图本设计的难点在软件编码与调试这一部分，软件这部分用C语言编写，C语言编写比较简单，而且看起来脉络清晰，明白，易懂。并且调试、修改起来也比较方便。编写时各个模块可以独立编写，各个模块用一个函数表示，需要时只需调用即可，最后再将各个模块联系起来。当然，各个模块程序的编写还是相当不容易的，需要多查阅资料与学习。重点在硬件设计，硬件设计主要就是各个模块的设计，其关键在于仪器选型和电路设计，如：显示电路用LED显示，键盘主要用于设定脉搏波速上下

6、限，不在此范围，则就报警。这部分也需多查阅资料，多多请教别人，多思考。工作计划起止日期日/月）周次内容进程备注2.25-3.31熟悉毕业论文的题目，查阅相关的资料3.4-3.102构思设计模块，撰写开题报告3.11-3.173理清思路，提出论文设计方案3.18-3.244论证方案3.25-3.315硬件设计各模块设计）4.1-4.764.8-4.1474.15-4.2184.22-4.289软件编码与调试4.29-5.5105.6-5.12115.13-5.1912撰写论文5.20-5.26135.27-6.214完成初稿6.3-6.915修改定稿，送审6.10-6.1616再修改并准备答辩6

7、.17-6.2317答辩6.24-6.3018四、主要参考文献不少于10篇，期刊类文献不少于7篇，应有一定数量的外文文献，至少附一篇引用的外文文献 is ameasure of the elasticity （or stiffnessof peripheral arterial blood vessels. The pulse referred to here will be thepressure pulse as opposed to the flow pulse measured by ultrasound Doppler.The pressure pulse velocity vari

8、es over the range from about 12 m s1 to15 m s1 in stiff peripheral arteries, whereas in normal arteries it has a velocityin the range of 7 to 9 m s1.The aimof this projectwas the development of a fast and easy to use systemfor the determination of peripheral arterial pulse wave velocity. The princip

9、leof the PWV measurement is based on simultaneous measurement of two pulsewaves at two different positions, such as the radial artery at the wrist andthe brachial artery just above the elbow. By determining the pulse transit timebetween these points and the distance measured between the two location

10、s,pulse wave velocity may then be calculated. The pressure pulse detection isdone by using two piezoelectric sensors which generate a measurable voltageat the output contacts if they are mechanically deformed. The deformationproduced voltage is first amplified and filtered and then digitalized with

11、a dataacquisition card. The analysis of the data obtained from the sensors includesa filtering process, the calculation of the PWV with three different methodsfoot-to-foot, cross-correlation and peak-to-peakand the determination of thearterial pulse rate.The sensor technique used in this work involv

12、es the piezoelectric effect in polyvinylidene fluoride （PVDF, which produces an output voltage in response to mechanical pressure on the material. Three methods of APWV determination are used: foot-to-foot APWV。 peak-to-peak APWV and cross-correlation APWV. The FFAPWV and CCAPWV methods are less sen

13、sitive to pressure wave reflections at bifurcations, etc in the arterial tree, than the PPAPWV method. Mean values and standard deviations were computed for all three methods and compared.Foot-to-foot APWV （FFAPWV. This is based on the velocity of the foot, orleading edge, of the pressure pulse wave

14、. The arrival times of the foot of the pulse wave attwopositions along the artery are recorded. If t is the difference in arrival times and s thedistance between the two recording positions （proximal and distal, the FFAPWV is simplyFFAPWV = s/t.Peak-to-peak APWV （PPAPWV. This is completely analogous

15、 to the FFAPWVexcept that the points of observation are the two （proximal and distal peaks of the pulse waveandPPAPWV = s/t.Apparent pulse wave velocity （AAPWV. The pressure wave may be represented as aFourier series,P（t = P0 +Pn sin（nt + nWhereP0 is the mean fluid pressure, n is the harmonic number

16、, Pn is the amplitude of the nthharmonic and n is the phase angle of the nth harmonic.The spatial rate of change of the phase for one harmonic based on two simultaneouspressure measurements separated by a distance _s along an artery, is related to the apparentarterial pulse wave velocity （AAPWV by t

17、he following equation,AAPWVn = （sn（f （360o/（x1x2WhereAAPWVn is the apparent pulse wave velocity for the nth harmonic, f is the heart rate,x1 is the phase angle for the proximal harmonic n and x2 is the phase angle for the distalharmonic n.Cross-correlation PWV. If the arterial pulse at the proximal

18、measurement position isrepresented by the pressure time series P（x1, t and that at the distal position by P（x2, t andthe cross-correlation coefficient is x1,x2（ , then will have a maximum value at some timelag.The correlation function can be expressed asx1,x2（ = （1/T P（x1, tP（x2, t dt.The value of a

19、t whichmaximumcorrelation occurs represents the transit time （_t of thepressure wave from position x1 to position x2 along the arterial segment. From the separationdistance and transit time data the correlation arterial pulse wave velocity isCCAPWV = （x2 x1/t.In this work normal, young test subjects

20、 were used, and it has the primary objectives of optimizing the measurement procedures and establishing the statistical spread and mean values of the observed PWVs for a specific peripheral arterial segment. Based on this, it is planned to use the system in clinical trials involving patients with pe

21、ripheral arterial disease （due to diabetes, hypertension, etc, pre-, during and post treatment （pharmaceutical or surgical.Analogue and digital circuitryAnalogue charge amplifier. Piezoelectricmaterials convert mechanical stress or strain into proportionate electrical energy, by producing a charge w

22、hen subjected to mechanical stress. The charge is converted to a voltage by an operational amplifier connected as a current integrator, called a charge amplifier. The signal output of the amplifier is approximately 30 mV. It is augmented by signal amplification.Analogue signal amplification . This i

23、s done by use of an inverting amplifier. Because a dc signal appears at the output of the charge amplifier, dc offset removal is essential and is implemented in the inverting summing The next phase of the analogue circuitry is a low pass filter to remove the 50 Hz noise interference.Digital controll

24、ed data acquisition and analysis. A data acquisition board （DAQ is required when the transducer signals need interfacing with a PC. The board contains 12 bit plus sign and a successive approximation and self-calibrating analogue-to-digital （ADC converter. The ADC incurs a systematic error known as the q