摘要
根据一维正弦条码对位移进行编解码的原理,提出了一种绝对位移和相对位移测量的新方法。该方法通过对一维正弦条码图像进行傅里叶频谱分析, 根据首条码的相位值进行粗定位,并对该条码进行中心几何定位实现连续位移的精确测定。误差分析表明:位移测量误差完全取决于首条码中心几何定位。为此,采用亚像素定位技术建立了正弦条码尺测位移的原理装置,并对 2米远处步距分别为 1.5cm 和 1mm 时正弦条码尺的两种垂直位移进行了测量,测量值的最大误差为 0.036mm,标准差优于 0.024mm。
A new method for measuring absolute and relative displacement is proposed according to the principle of coding and decoding for displacement with 1-D sinusoidal bar code. Through Fourier spectrum analysis for 1-D sinusoidal bar code image, the phase of the first bar code can be calculated to find the coarse position, and then the precise position can be found by geometrically positioning the first bar center. Error analysis shows that the displacement measuring error entirely depends on geometric positioning precision of the first bar code center. For this reason, based on sub-pixel positioning technique a principal setup is constructed to make vertical displacement measurement of sinusoidal bar code in two cases where the step lengths are 1.5 cm and 1mm respectively for an identical distance 2m. The measurement results show that the maximum measuring error is 0.036 mm and the standard deviation is 0.024 mm.
出处
《光电工程》
EI
CAS
CSCD
北大核心
2005年第3期44-46,65,共4页
Opto-Electronic Engineering
关键词
正弦条码
位移测量
图像测量
Sinusoidal bar code
Displacement measurement
Image measurement
