High-speed decoding method for sine-cosine encoder based on FPGA

Abstract

The invention relates to a high-speed decoding method for a sine-cosine encoder based on an FPGA. The method is characterized by comprising the following steps of step 1.carrying out encoder signal processing on two paths of sine-cosine signals output by the sine-cosine encoder and one path of zero signals; step 2.realizing coarse-level angle signal measurement through the FPGA in order to obtaina coarse-level pulse edge count value; step 3.realizing fine-level angle signal measurement through the FPGA in order to obtain a fine-level angle value; and step 4.obtaining a current encoder angle value through coarse-fine coupling resolving according to the coarse-level pulse edge count value and the steering of the sine-cosine encoder of step 2, and the fine-level angle value of the step 3. According to the method, the high-speed and high-precision measurement of the angle is realized under a condition that the encoder with the low cost and the small volume is used.

Description

technical field [0001] The invention belongs to the technical field of rotary inertial system control and measurement, and relates to a high-speed sine-cosine encoder decoding device, in particular to an FPGA-based high-speed sine-cosine encoder decoding method. Background technique [0002] In the rotary inertial navigation system, the system attitude is one of the most important output indicators, and the system attitude is obtained by superimposing the attitude calculated by the IMU and the angle of the rotating mechanism. Therefore, a high-speed and high-precision angle measurement device is the guarantee of the system design. Commonly used angle measuring devices include resolvers and photoelectric encoders. The precision and reliability of the resolver are relatively good, but its price is high, and it is often used in ultra-high-precision inertial equipment; compared with the resolver, the photoelectric encoder has a lower cost, a variety of structures, and is easy to...

AI Technical Summary

Problems solved by technology

[0003] At present, the existing sine-cosine encoder decoding devices are mostly completed by single-chip microcomputer or DSP. Although it is easy to implement, it is difficult to improve the data acquisition speed. At the same time, it is difficult for the traditional low-precision AD conversion method to exert the signal subdivision performance of the sine-cosine encoder.

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