Pseudo random code track grating ruler and reading method thereof

Abstract

The invention discloses a coding method of a pseudo random code track grating ruler, the pseudo random code track grating ruler made by using the coding method of the pseudo random code track gratingruler and a method for reading the pseudo random code track grating ruler. The pseudo random code track grating ruler includes a linear guide rail, a reading head and a pseudo random code track grating ruler body; the pseudo random code track grating ruler body includes a main ruler, a vice ruler and an incremental code track; the code tracks of the main ruler and the vice ruler are grating grooves which are arranged continuously at non-equal internals and are arranged according to the coding method, and the incremental code track is periodic grating grooves which are arranged continuously atequal internals. The grating ruler is high in resolution ratio and large in range capacity, the startup identification position distance is short, a mathematical derivation method of an absolute valuecode track is simple, and the manufacturing technique of products is simplified.

Description

technical field [0001] The invention relates to the research field of grating ruler position measurement technology, in particular to a pseudo-random code track grating ruler and a reading method thereof. Background technique [0002] The grating ruler is a measurement feedback device that uses the optical principle of the grating. Grating rulers are often used in the closed-loop servo system of CNC machine tools for the detection of linear displacement or angular displacement. The signal output by the grating ruler is a digital pulse, which has the characteristics of large detection range, high detection accuracy and fast response speed. [0003] The current grating ruler is mainly divided into incremental grating ruler and absolute grating ruler. The measuring principle of the incremental grating scale is to modulate the light into moiré fringes through two relatively moving gratings, and obtain the displacement variation after counting and subdividing the moiré fringes,...

AI Technical Summary

Problems solved by technology

The code channels used in this patent are multi-dimensional multiple pseudo-random code channels. As the range increases, the number of code channels will also increase, which causes the problem of complex overall measurement, reading and calculation structures of the grating ruler; in addition, the encoding method It adopts full-scale coding. This method is a cyclic coding method. Pseudo-random codes appear periodically. The main reason is to increase the parallel code method of the code channel to expand in the length direction. As the length increases, the technical complexity increases significantly, which is not conducive to Applied to grating scales with large measuring range length

Images