基于单片机的智能水平仪设计

摘要

电子水平仪是一种非常普遍的测量小角度的量具。用它可测量对于水平位置的倾斜度。基于传感器、数字信号处理、单片机技术的数字水平仪是当前倾角测试仪器数字化发展的方向。

本毕业设计就是采用STC89C52单片机和ADI公司生产的三轴加速度传感器ADXL345相结合，利用ADXL345三轴加速度传感器感应水平倾角，通过单片机的控制以及运算将倾角以数值的形式直接在LCD显示屏上进行显示、处理，从而使角度测量变得方便、快捷，实现了倾角的高精度测量。通过ADXL345三轴加速度传感器原理，提出了使用软件和硬件结合的自动校正技术进行测量角度，最大限度简化了电路，提高了系统的稳定性和可靠性。

通过对本课题的研究，让我对水平仪有了一定的了解，在未来水平仪将在建筑方面起着重要作用，并且随着时代发展，水平仪对角度的测量将越来越精细，随着光学应用领域的不断扩展，也相应的产生了一些基于光电原理的光电式水平仪和激光式水平仪，光电原理的应用将是未来水平仪的发展方向。

关键词：智能水平仪；单片机；ADXL345；角度

Abstract

Electronic level gauge is a very common small angle measurement. Measurement for the horizontal position of the inclination to use it. Based on the digital level sensor, digital signal processing, computer technology is the current development of digital instrument tilt testing instrument in the direction of.

This graduation design is the use of three axis accelerometer ADXL345 microcontroller STC89C52 and ADI company production of combination, using the ADXL345 three axis acceleration sensor level angle, processing through the MCU control and operation will dip in numerical form directly in the LCD screen display,, so that the angle measuring is convenient, quick, realize high precision measurement of angle. The principle of the ADXL345 three axis accelerometer, and proposes to use the combination of hardware and software of the automatic calibration technique for measuring the angle, the maximum simplifies the circuit, improves the stability and reliability of the system.

This graduation design is the use of three axis accelerometer ADXL345 microcontroller STC89C52 and ADI company production of combination, using the ADXL345 three axis acceleration sensor level angle, processing through the MCU control and operation will dip in numerical form directly in the LCD screen display,, so that the angle measuring is convenient, quick, realize high precision measurement of angle. The principle of the ADXL345 three axis accelerometer, and proposes to use the combination of hardware and software of the automatic calibration technique for measuring the angle, the maximum simplifies the circuit, improves the stability and reliability of the system.

Keywords: Intelligent level; MCU; ADXL345; angle

目录

1 绪论 (1)

1.1 课题研究背景和意义 (1)

1.2 国内外水平仪发展现状和趋势 (1)

1.3 系统设计的主要工作 (1)

1.4 论文结构及安排 (2)

2 三轴加速度传感器感应原理 (3)

2.1 ADXL345工作原理 (3)

2.2 ADXL345寄存器映射 (5)

2.3 ADXL345主要寄存器定义介绍 (6)

2.4 测量倾斜角度原理 (8)

2.4.1 加速度传感器进行倾角测量简介 (8)

2.4.2 ADXL345测量角度原理 (9)

3 水平仪总体设计 (12)

3.1 水平仪硬件设计 (12)

3.1.1 单片机模块 (13)

3.1.2 LCD液晶显示模块 (14)

3.1.3 ADXL345接口设计 (16)

3.1.4 ADXL345加速度传感器模块 (18)

3.2 水平仪软件设计 (20)

3.2.1 I2C总线协议分析 (21)

3.2.2 液晶显示驱动程序设计 (25)

3.2.3 ADXL345加速度传感器软件模块 (27)

3.2.4 ADXL345加速度传感器误差校准 (28)

4 实验数据及总结 (30)

结论 (33)

致谢 (34)

附录A 英文原文 (37)

附录B 汉语翻译 (41)