【作者】 胡汝豪；

【导师】 刘丽华；

【作者基本信息】 哈尔滨工业大学 ， 仪器科学与技术， 2010， 硕士

【摘要】 表面粗糙度是评定工件性能的一项重要指标,直接影响到工件的摩擦系数、抗疲劳能力等性能以及外观,因此,作为测量表面粗糙度的重要仪器,轮廓仪在机床、汽车、仪器仪表等行业中运用广泛。轮廓仪的性能优劣主要取决于测量精度,而信号调理电路的性能以及粗糙度数字滤波器的好坏直接决定着轮廓仪的测量精度。在查阅相关资料的基础上,本文首先对国内外的粗糙度测量技术进行了分析,在此基础上设计了轮廓仪的信号调理电路与数字滤波器,并将所研究的技术运用到了Talysurf5型轮廓仪的改造过程中。对轮廓仪信号调理电路的功能与结构进行了分析,并研制了正弦波振荡电路、交流放大电路、带通滤波电路、量程切换电路、相敏检波电路以及低通滤波电路。研制了模数转换电路以及高精度的参考电压电路。分析了光电耦合抗干扰的原理,并运用光电耦合器来对信号调理电路的模拟部分和数字部分进行隔离。分析了数字滤波原理,推导出2RC、相位校正、高斯滤波这三种数字滤波方法的滤波方程,并在软件上实现了这三种数字滤波方法。根据国家标准GB/T 3505-2009中关于粗糙度评定参数的定义,推导了主要粗糙度评定参数的计算流程。运用VB和VC混合编程的方式编写了表面粗糙度评定软件。将本文所设计的信号调理电路和粗糙度评定软件运用到Talysurf5型轮廓仪的改造中,并对改造后轮廓仪进行了校准。更多还原

【Abstract】 Surface roughness is an important plant of work piece, and it will directly affects the performances such as coefficient of friction, anti-fatigue, performance, and so on, so, as an important instrument for measuring surface roughness, profilometer is widely used in machine tools, automobiles, instrumentation and other industries. The performance of profilometer mostly depends on the precision of measurement, which is absolutely determined by the performance of signal conditioning circuit and digital filter. Referring to great lot of scientific and technical literatures which are relevant with surface roughness measurement, this dissertation, firstly analyzes the present condition of roughness measurement techniques domestically and abroad, on this basis, signal conditioning circuit and digital filters are developed, and applied to the process of the transformation of Talysurf5 type profilometer.This dissertation analyzes the function and structure of signal conditioning circuit, and develops sine wave oscillating circuit, AC amplification circuit, band pass filter circuit, range switching circuit, phase sensitive detection circuit and a low pass filter circuit. Develops analog-digital conversion circuit and high-precision reference voltage circuit. This dissertation also analyzes the anti-jamming principium of photocoupler, and uses photocoupler to isolate the analog part of signal conditioning circuit from the digital part.This dissertation derives the filtering equations of 2RC filter, phase-correct filter, and Gaussian filter from corresponding digital filtering principles, and also implements these three digital filters in software. According to the definitions on roughness evaluation parameters of national standard GB/T 3505-2009, this dissertation derives the process of calculating main roughness evaluation parameters. Develops surface roughness evaluation software based on VB and VC. Applies both the signal conditioning circuit and this software to the transformation process of Talysurf5 type profilometer, and calibrates it.更多还原