基于单片机的儿童身高、体重测量系统的设计

基于单片机的儿童身高、体重测量系统的设计(任务书,开题报告,外文翻译,论文12900字)
摘  要
身高和体重是儿童成长发展的重要标准，而测量身高和体重也是儿童体检时必不可少的项目。家长和医生可以通过体重、身高的改变趋向来大致判断孩子的发育情况，随之作出相应的培养计划,这就要求有一个能够方便地测量儿童身高体重的仪器。
本次设计是一个基于51单片机的儿童身高体重测量仪。本设计硬件模块包括电源模块、单片机最小系统模块、LCD显示模块、超声波模块、AD转换模块、压力传感器模块、串口通信模块。软件程序包括主程序、系统初始化程序、AD转换器通信程序、超声波信号发送与接收程序、LCD驱动程序、串口通信程序、按键扫描程序。本设计以51单片机为基础，凭借人的重量使压力传感器形变从而改变电阻，而电流与电压也随之改变，在经过AD转换将转换过后的数字信号传入51单片机，来测量体重。同时利用超声波的指向性强，在传播过程中能量损耗缓慢等特性，在介质中声波的传播速度为340m/s，再配合所用时间计算出传播距离，实现了身高的测量。最后控制单片机将数据显示在显示屏上，并通过串口将数据传送到电脑上。
本设计可以同时测量儿童的身高和体重，在LCD1602上显示出来并上传到电脑上分析。基于单片机的儿童身高体重测量系统成本低，设计简单，显示清晰，基本满足需求。

关键词：STC89C52  超声波  HX711  LCD  串口通信

Children's height and weight measurement system based on single chip microcomputer
Abstract
Height and weight are important criteria for children's growth and development,and measurement of height and weight is essential for children's physical examination.Parents and doctors can determine the child's development by changing the weight, height, and then make the appropriate training plan.This requires an instrument that can easily measure the height and weight of a child.
This design is based on the 51 single chip computer height and weight measuring instrument.The design of the hardware part includes power module, MCU minimum system module, LCD display module, ultrasonic module, AD conversion module, pressure sensor module, serial module.The software part includes the main program, the system initialization program, AD converter communication program, ultrasonic signal transmitting and receiving program, LCD driver, serial program, key scanning program.This design with 51 single chip microcomputer as a platform, with the weight of the pressure sensor deformation and resistance to change, and current and voltage also changed, in after AD conversion will be digital signal after conversion of the incoming MCU to measure weight.At the same time, the use of ultrasonic with high directivity, in the communication process energy loss characteristics, such as slow, in the medium acoustic propagation velocity 340m / s, together with the time to calculate the propagation distance, the realization of the height measurements.In the end, the data is displayed on the display screen, and the data is transmitted to the computer through the serial port. [资料来源：www.THINK58.com]
This design can measure the height and weight of children at the same time, the LCD1602 is displayed on the computer and uploaded to the computer analysis.Based on single chip microcomputer children's height and weight measuring instrument low cost, design is simple, show clearly, basically meet the needs.
Key words: STC89C52; ultrasonic; HX711; LCD; serial communication
 

目  录
摘  要    I
Abstract    II
第一章  绪论    1
1.1  引言    1
1.2  研究现状    2
1.3  论文组织结构    3
第二章  系统总体方案设计    4
2.1  总体方案    4
2.2  主控制器的选择    5
2.3  测距模块的选择    6
2.4  压力传感器的选择    6
2.5 AD模块的选择    7 [资料来源：http://think58.com]
2.6 LCD模块的选择    7
2.7 串口模块的选择    8
第三章  系统硬件电路设计    9
3.1  系统设计思路与功能设计    9
3.2 单片机最小系统    9
3.2.1  晶振电路    9
3.2.2  复位电路    10
3.2.3  电源电路    11
3.3  超声波电路    11
3.4  按键电路    12
3.5  液晶显示电路    12
3.6压力传感器模块    13
3.7 HX711AD转换模块    15
3.8总体硬件工作原理    15
3.9 单片机IO的资源分配    15
第四章 系统软件设计    16
4.1  概述    17
4.2  系统初始化函数的编写    19
4.3 HX711 AD转换器通信函数的编写    19
4.4 按键检测函数的编写    20
4.5 超声波模块函数的编写    21

[资料来源：http://THINK58.com]

4.6 液晶屏驱动函数的编写    22
4.7 串口通信函数的编写    23
第五章  调试    25
5.1 硬件的制作    25
5.2 硬件的开发平台    25
5.3 软件的调试    26
5.4 软件的开发平台    26
第六章  总结与展望    28
参考文献    29
致谢    31

[来源：http://www.think58.com]