【作者】 朱维娜；

【导师】 周文祥；

【作者基本信息】 西南交通大学 ， 精密仪器及机械， 2012， 硕士

【摘要】 光栅技术应用极为广泛,除应用于大型精密数控机床、测量仪器外,在中小型测量设备上也有诸多应用,近年来在便携式精密测量仪器领域也逐渐推广应用,如西南交通大学牵引动力实验室研发的五连杆轮轨测量仪中也用到光栅编码器来测量角度。光栅细分是实现精密测量的必由之路,为跟踪该技术的发展,提高轮轨测量仪精度,本文对光栅细分技术进行了如下研究：首先,对光栅测量原理进行分析,研究了经典细分法方法及新型细分方法的特点,根据现代数字信号处理器(DSP)的发展现状,结合设计中采用直线式粗光栅,选取了一种软硬件结合的幅值相位细分法,设计了系统总体方案,对细分系统的主要组成模块进行了选择及功能设计其次,设计了细分硬件电路：差分放大电路滤除光栅尺输出信号中的直流分量,然后一路通过过零比较电路将正弦波转换为方波,另一路在通过低通滤波电路滤除高频噪声后,两路分别通过不同参数的加法及比例运算电路对幅值进行调节,以满足各自后续电路对输入信号的要求；DSP2812芯片的正交编码模块用于方波信号的辨向和计数,其A/D转换模块检测光栅信号正弦电压波形,串口通信模块向外发送细分计数结果。再次,编写了DSP软件：对QEP、 A/D模块及串口的功能进行设置,设计了数字滤波程序对采样数进行滤波,零点补偿程序模块消除温漂,设计幅值相位细分表,编写查表程序,实现了非完整脉冲位移细分计数,设计串口发送程序,实现了细分结果的正确发送。最后分析了光栅细分系统的测量误差,介绍了系统调节、测试情况,结果表明,系统的分辨率由0.04mm提高到0.001mm。更多还原

【Abstract】 Grating technology is widely used. In addition to used in large precision CNC machine tools, measuring instruments area, it also used in the portable precision measuring instruments also gradually popularized by recent years. Traction Power State Key Laboratory of Southwest Jiaotong University developed five-bar mechanism wear precision rofilometer is also used the Grating measurement to measuring the angle. Grating subdivision is an important way to realization precision measurement, in order to tracking the technology development, improve the measurement accuracy of five-bar mechanism wear precision rofilometer, this paper did research on grating subdivision technology as following:First, analysis the principle of grating measurement, studied on the characteristic of classics subdivision method and new subdivision method, according to the current development of modern digital signal processor (DSP), combined with the actual grating, selects a the amplitude phase subdivision method combining hardware and software. Designed the overall program, selecting and functional designing the main subdivision system function modules.Secondly, designing the hardware circuit of subdivision:DC component in the output signal filtered by differential amplifier circuit, then one road sine wave converted to square wave when passed over zero-crossing comparison circuit; the other road filtered the high-frequency noise by a low-pass filter circuit, the two road signals through separate addition and proportion arithmetic circuit with different parameters of for amplitude regulation for amplitude regulation to meet their the requirements of signa input subsequently; The orthogonal coding module of DSP2812chip was used to identify the direction and count, its AD conversion module detects the grating signal voltage waveform, serial communication module is used to send subdivision counting results.Once again, the preparation of the DSP software:initialized and set the QEP, AD module and serial port, designed the program of digital filtering on the number of samples is filtered, zero compensation program module to eliminate temperature drift designed amplitude phase subdivision table, writing the look-up table procedures, realized displacement of nonholonomic pulse subdivision count, designed the program of serial port sending to realized the correct data transmission.更多还原