摘要
为了提高基于条纹计数的位移测量在存在强振动的情况的测量精度与可靠性,提出了一种基于迟滞比较器的条纹辨向、计数与细分电路。该电路用迟滞比较器将正弦信号变换为方波信号,并为上升与下降跳变设置不同的门限电压,屏蔽信号在零点附近抖动引起的高频方波的出现。波形变换之后得到的方波由微分器与逻辑电路进行辨向产生双向计数脉冲。由于高频方波在微分之前被屏蔽,则误计数脉冲也被屏蔽。实验证明,这种电路具有很强的抗干扰能力,适用于存在振动及频繁换向情况下位移测量的条纹计数与细分。
In order to improve the accuracy and reliability of the displacement measurement based on fringe counting with vibrations, a novel direction recognizing and subdivision circuit for fringe counting based on hysteresis comparators is introduced. In the circuit, hysteresis comparators are adopted to convert sinusoidal signals into square signals with different reference voltages as upper threshold and down threshold. Owing to the existing of the difference of the two thresholds, which is called hysteresis voltage, high frequency square signals due to high frequency noises in the sinusoidal signals can be shielded. Therefore when the square signals are input into direction recognizing and counting circuit which is composed of differentiators and logic circuit, counting error will be restrained. Experimental testing on the circuit verify its good anti-disturbances ability. So it is very preferable for fringe counting based displacement measurement with vibrations and frequent direction-reversing.
出处
《光学仪器》
2010年第5期58-63,共6页
Optical Instruments
基金
973国家重点基础研究发展计划(2007CB714005)
湖北省自然科学基金重点资助项目(2008CDA029)
关键词
条纹
迟滞比较器
误计数
细分
fringe
hysteresis comparator
counting error
subdivision
