A zero-bias self-calibration mems gyroscope and its zero-bias self-calibration method

Abstract

The invention a MEMS gyroscope zero-bias self-calibration method based on driving / detecting modal inversion, and the MEMS gyroscope zero-bias self-calibration method is capable of solving problems inthe prior art that drift of fully-symmetrical MEMS gyroscopes is caused and power-on zero-bias of a plurality of times is different. According to the MEMS gyroscope zero-bias self-calibration method,gyroscope working characteristics are taken into consideration, a gyroscope dynamic model is taken as a base, the change rules of two working modes before and after driving modal and detecting modal inversion are given, switch of the circular gyroscope between the two working mode is realized using a signal processing circuit. The difference of the detection signals at the adjacent working modes is obtained, so that MEMS circular gyroscope zero-bias self-calibration is realized at last. The MEMS gyroscope zero-bias self-calibration method is capable of extracting zero-bias signals effectively,inhibiting zero-bias drift, and increasing the precision of the MEMS circular gyroscopes.

Description

technical field [0001] The invention relates to a MEMS gyroscope zero-bias self-calibration method, in particular to a MEMS gyroscope zero-bias self-calibration method based on drive / detection mode inversion, which is suitable for a structurally symmetrical MEMS ring gyroscope to realize zero-bias online self-calibration. calibration. Background technique [0002] As an important inertial device, MEMS gyroscope has the advantages of small size, low power consumption, low cost, strong anti-overload ability, etc., and has a wide range of applications. However, the performance of MEMS gyroscopes is affected by various factors such as process errors and the environment, resulting in problems such as zero bias in the output, easy drift of zero bias, and inconsistent zero bias after multiple power-on. The signal is extracted from the useful angular velocity signal, which limits its application. [0003] Temperature is an important factor affecting the accuracy of MEMS gyroscopes...

AI Technical Summary

Problems solved by technology

The currently reported methods to improve the accuracy of gyroscopes mainly include temperature control and temperature compensation. However, these two methods have certain limitations in terms of design and compensation effects.

Among them, temperature control requires the design of additional temperature control components, which will increase the size and power consumption of the gyro system. In addition, the dynamic performance of the constant temperature control, such as rapidity, stability, and hysteresis, will affect the performance of the gyroscope, and there are design difficulties.

Temperature compensation needs to establish a temperature compensation model through high and low temperature tests, and the temperature sensor is required to truly characterize the working environment of the gyroscope resonant ring. In addition, the accuracy of the temperature sensor and the repeatability of the gyroscope are high, and the zero bias of the gyroscope - temperature Models are subject to change and require regular calibration, adding additional work time

In addition, the gyroscope has the inherent disadvantage of relatively poor zero bias repeatability. In order to eliminate the problem of inconsistent zero bias after multiple power-on of the gyroscope, improve the zero bias repeatability, and reduce the cumulative error, it is necessary to study the zero bias on-line automatic Calibration method

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