心音产生与控制系统的设计.doc

毕业设计(论文)心音产生与控制系统的设计心音产生与控制系统的设计系 别自动化工程系专 业生物医学工程班 级50616姓 名孟令男指导教师贺忠海2010 年 6 月 16 日- 1 -东北大学毕业设计（论文）摘 要心音（heart sound）是一项反映人体器官生理及病理状况的重要指标，临床医学上广泛应用心音听诊对心脑血管方面疾病进行诊断，因此需要开发一种心音产生与分析系统，以供实习医生训练听诊使用传统听诊方法由于难以捕捉一些微弱的心音信号，诊断结果易受听诊者主观经验的影响，同时诊断不具有重复性、结果无法保存，无法达到实习医生训练听诊的目的为此，本文提出一种心音产生与控制系统的设计方案本系统可以对采集到的同一心音进行重复听诊该系统增强对心音分析和诊断的准确性，减少了传统听诊中主观经验的影响，使实习医生对心音的学习简单化、实践化，最终达到实习医生训练听诊的目的本文首先介绍了人心音产生与控制系统的研究背景、课题目的及意义；从心音信号的检测和处理两方面分析国内外心音的研究现状在此基础上，提出心音产生与控制系统的总体设计方案，该方案包括系统的设计要求、总体结构设计、系统功能设计三方面内容，为下一步系统的详细开发与设计奠定良好的基础。

硬件设计方面，主要包括心音信号采集模块、录放电路模块、主控模块、USB 通信模块、D/A 转换模块采集模块采用驻极体传声器作为传感器，完成心音信号向电信号的转换；录放模块选用 ISD（Information Storage Device）公司的 ISD4003-04M 芯片，由交流小信号放大电路、心音录制与回放电路和功率放大电路组成；主控模块选用 Microchip 公司的 PIC16F917 芯片，实现对录放模块、USB 通信模块和 D/A 转换模块的控制；USB 通信模块实现了主控模块和计算机之间的通信，把采集到的心音信号送入主机端以供分析；D/A 转换模块主要完成数模转换，输出心音信号软件设计方面，实现了系统初始化、心音录放流程及相应程序和 USB 固件设计等模块的功能关键词：心音产生；听诊；PIC16F917 单片机- 2 -东北大学毕业设计（论文）Heart Sounds Generation and Control System AbstractHeart sound is an important content of human organs physiology and pathology. Auscultation is one of the major diagnosis methods for the disease of cardio-cerebrovascular system. Therefore it is needed to develop a system of heart sound generation and control as a physiological module in medical patient simulator.It is difficult for traditional method of auscultation to capture some weak physiological signal. Meanwhile the diagnosis results are subject to be influenced by auscultator. As to the residency it can’t be repeated and saved so not suitable for the goal of training. In this thesis, a design project of heart sound generation and control system in medical patient simulator is introduced. This system not only may repeat the same heart sound but also may display the waveform on the computer, which strengths the objectivity of diagnosis. Simultaneously, the heart sound data can be saved and decomposed on the computer, so as to simplify the study of heart sound.This dissertation introduces the research background, significance and status of heart sound generation and control system in medical patient simulator at home and abroad. On this basis, overall design is put forward. There are three aspects: the system technical content, the designing requirements and the system function. They are the indications of the system’s hardware and software design.The hardware system mainly includes modules of signal input, recording and playing circuit, main, USB communication and D/A. Electric microphone is used as a sensor of signal input module, accomplishing the signal conversion. Recording and playing module is designed by choice of ISD’s ISD4003-04M, which is composed of AC small signal amplifying circuit, recording and playing circuit and power amplification circuit. The chip of Microchip’s PIC16F917 is used in main module. It controls the module of recording and playing circuit, USB communication and D/A conversion. The USB communication module connects the main module and computer, which sends the signal to computer for analysis. D/A conversion module realize data to analog conversion, outputting heart sound.- 3 -东北大学毕业设计（论文）The software design includes the flow of the system software, system initialization and flow of the recording and playing module. Then introduce the design flow of USB firmware, which is composed of main cycle, interrupt service routine, USB standard request and firm request progress. USB firmware is the driver of USB equipment and decides the transmission efficiency of USB communication module.Keywords： Heart Sound Generation; Auscultation; PIC16F917 MCU- 4 -东北大学毕业设计（论文）目录摘 要.........................................................................................................................................1ABSTRACT................................................................................................................................2第一章 绪 论.............................................................................................................................61.1 论文的研究背景..................................................................................................................71.2 论文的研究意义..................................................................................................................71.3 本论文的主要内容..............................................................................................................8第二章 心音产生与控制系统总体设计...................................................................................92.1 系统设计要求......................................................................................................................92.2 系统功能和外围接口..........................................................................................................92.2.1 系统功能描述...........................................................................................................92.2.2 系统外围接口描述...................................................................................................92.3 系统总体架构...。