Position coding-based displacement detection system and detection method

Abstract

The invention relates to a position coding-based displacement detection system and detection method. The position coding-based displacement detection system comprises a workbench, an optical imaging system, a planar array CCD sensor, an image acquisition card, a PC and a power module, wherein a position coding scale is fixed on the workbench. Two coded images of a start position and a stop position of the position coding scale on the workbench in the movement direction are collected by using the planar array CCD sensor; and image processing, such as correction, filtering and edge extraction, and decoding and positioning calculation are carried out on the coded images to obtain displacement of the workbench. Non-contact displacement measurement is carried out through the imaging system andthe CCD sensor, so that the position coding-based displacement detection system is simple in structure, easy to miniaturize, simple in coding, high in anti-jamming capability and easy to process and install; and different coding cycles are represented with different widths of ''1'' value score lines at coded bits, so that the displacement measurement range is expanded and the displacement measurement accuracy still can be ensured. The displacement detection system has the characteristics of being low in manufacturing cost, simple in operation and high in measurement accuracy.

Description

technical field [0001] The invention relates to a displacement detection system and method, in particular to a non-contact displacement measurement device and detection method suitable for precision processing workbenches such as wide range, high-precision displacement measurement, photoelectric conversion, and image processing. Background technique [0002] Precision displacement measurement technology plays a very important role in precision machinery manufacturing, semiconductor processing and other fields, but it is very difficult to meet the requirements of large range, high resolution and high precision at the same time. At present, the long grating digital display sensor is the most commonly used length precision measuring instrument, which is simple, reliable and has high precision. However, its measurement range is limited by the length of the grating ruler, and as the length increases, the accuracy of the instrument decreases. Position encoders are sensors that me...

AI Technical Summary

Problems solved by technology

The number of digits of the coded value of the barcode in the continuous combination code is proportional to the measurement range. The larger the measurement range, the more digits of the coded value of the barcode, and the higher the sensor size or resolution of the imaging system is required, otherwise the measurement accuracy will be affected; the periodic combination code is One coded bit is taken from each set of n coded sequences to form an n-bit coded value. The width of each coded bit is different. It is necessary to accurately extract the width of each coded bit to obtain the coded value. The image processing and decoding process is relatively complicated.

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