Displacement detection system and detection method based on position coding

Abstract

The invention relates to a displacement detection system and detection method based on position coding, which is composed of a worktable fixed with a position coding ruler, an optical imaging system, an area array CCD sensor, an image acquisition card, a PC and a power supply module. The present invention uses an area array CCD sensor to collect two coded images of the start and end positions of the position coding ruler on the workbench in the moving direction, performs image processing such as correction, filtering, and edge extraction on the coded images, as well as decoding and positioning calculations, and obtains the position of the workbench. displacement. The invention uses an imaging system and a CCD sensor to perform non-contact displacement measurement, and has a simple structure and is easy to miniaturize; it has simple coding, strong anti-interference ability, and easy processing and installation; Encoding cycle, thereby expanding the range of displacement measurement, and can still ensure the accuracy of displacement measurement. The displacement detection system has the characteristics of low manufacturing cost, simple operation and high 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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