Anti-interference and anti-noise subdivision processing method for single-loop absolute encoder

Abstract

The invention discloses an anti-interference and anti-noise subdivision processing method for a single-loop absolute encoder. According to the method, first, a centroid algorithm is adopted to estimate respective pulse centers of a plurality of pieces of encoding disk depiction image data within a CCD observation range, then a subdivision matrix is constructed according to the positions of the pulse centers, respective subdivision weights of depiction line groups are solved through a matrix decomposition method, low weights are allocated to the depiction line groups under great interference and noise pollution, large weights are allocated to the depiction line groups under a small interference influence, and therefore overall measurement precision is improved. The method has the advantagesof high precision, interference resistance and noise resistance and is quite suitable for being applied to precise angular instruments such as an electronic theodolite and a total-station instrument(single-code-channel absolute encoding mode) operating in a severe working condition environment for a long term.

Description

technical field [0001] The invention belongs to the technical field of photoelectric measurement, and in particular relates to a single-turn absolute encoder anti-interference and noise subdivision processing method. Background technique [0002] The single-turn absolute encoder is mainly composed of a shaft system, a light source, a single-turn absolute encoder disk, a CCD read head, a measurement circuit board and other components, as well as algorithm software. The specific measurement scheme is: with the rotation of the shaft system, the incident light emitted by the light source is transmitted Pass the coded dial and irradiate the coded light and dark spot stripes containing angle information to the photosensitive surface of the linear array CCD, and then the signal processing circuit board sends the CCD timing signal to drive the CCD to work, and at the same time collect the light and dark of the code disc projected on the photosensitive surface of the CCD The fringe i...

AI Technical Summary

Problems solved by technology

Although the interpolation method and binarization method are simple to implement, the accuracy is low; the centroid method has high subdivision accuracy, but when the individual pixel signal of the CCD is disturbed and collapses (such as the code disk is polluted by dust particles in the air or the measurement circuit is affected by the outside Strong electromagnetic field interference will greatly reduce the quality of the photoelectric signal) It is easy to appear "double peak" phenomenon which seriously affects the measurement accuracy

It is not difficult to see that the traditional subdivision method is either difficult to meet the requirements of algorithm accuracy, or is greatly affected by environmental factors, and the algorithm's anti-interference and anti-noise adaptability is insufficient

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