摘要电气化铁路的快速发展对接触网测量技术提出了更高的要求。激光测距技术是接触网测量系统的关键技术之一，相比其他测距方式，激光测距具有精度高、方向性强、稳定性强等特点。以单片机为核心，配置步进电机进行软硬件开发，结合激光测距技术与自动控制技术，实现了接触网测量的自动化，加快了铁路现代化的发展进程。75150

本设计首先简单介绍了激光测距的几种方法，并对脉冲-相位式激光测距进行详细介绍。根据激光测距的特点，给出了总体的设计方案。其次是对ATMEL公司的AT89C52单片机的结构与工作原理的介绍，针对高精度的短程激光测距要求，使用单片机来代替专用的集成电路来计算与控制，配置步进电机，结合激光测距模块，达到了精度高、成本低、速度快、便于携带的要求。

毕业论文关键词：接触网  激光  测距  单片机

Design of automatic distance measuring system based on MCU

Abstract The rapid development of electrified railway put forward higher requirements to the measurement technology of the contact network。 Laser ranging technology is one of the key technologies of the contact network measurement system。 Compared with other methods, the laser ranging has the characteristics of high precision, strong directivity, strong stability and so on。 With single chip microcomputer as the core, the development of hardware and software of the stepper motor is configured, the automatic control technology of the laser ranging technology and automatic control technology are combined to realize the automatic measurement of the contact network, and speed up the development process of the modernization of the railway。

In this design, we first introduce several methods of laser range finder, and introduce the method of pulse phase laser ranging。 The overall design scheme of single chip computer ranging system is proposed。 Followed by introduction of structure and working principle of ATMEL Corporation AT89C52, according to the requirement of high precision of range finder, the use of single-chip microcomputer to replace the special integrated circuit to calculate and control, with laser ranging module, achieves the high accuracy, low cost, fast, portable requirements。

Key Words: contact net  laser  ranging  microcontroller

目  录

1 绪论 4

1。1研究背景及意义 4

1。2国内外发展现状 4

1。3本设计的要求 5

1。3本设计主要研究内容 6

2测量仪总体设计方案 6

2。1系统总体硬件组成 6

2。1中央处理器的设计选型 7

3激光测距模块电路设计 8

3。1激光测距特点及方法介绍 9

3。2脉冲-相位式激光测距技术 11

3。3激光发射与接收模块设计 14

4步进电机细分驱动模块设计 16

4。1步进电机的构造及特点 17

4。2步进电机选型与设计 17

5红外键盘控制及显示方案设计 17

5。1电源模块设计 18

5。2外遥控及按键模块设计 18

5。3LCD显示模块设计