Autonomous calibration method of MARG sensor based on MEMS

Abstract

The invention discloses an autonomous calibration method of an MARG sensor based on MEMS. The method comprises the three calibration steps of: firstly carrying out error correction on a triaxial accelerometer, i.e. performing error correction on the accelerometer through an ellipsoid fitting method, thus obtaining a gravity vector provided by the accelerometer after correction; secondly, conducting error calibration on a triaxial magnetometer, i.e. taking a gravity vector provided by the accelerometer obtained by calibration in the first step as an auxiliary vector of a dot product invariant method to correct the magnetometer; and finally, performing error calibration on a triaxial gyroscope, i.e. calibrating the gyroscope by using the calibrated measurement value of the triaxial vector field as an internal reference standard and using a cross product calibration method. According to the calibration method provided by the invention, the performance of a low-precision MEMS sensor is obviously improved, and the calibration method has the advantage of low cost.

Description

technical field [0001] The invention relates to the technical field of inertial navigation systems, in particular to an autonomous calibration method based on MEMS sensors. Background technique [0002] The inertial navigation system is a complete three-dimensional dead reckoning navigation system, which can output three-dimensional navigation information independently. Inertial sensors include accelerometers and gyroscopes. The inertial measurement unit (IMU) is the sensing component in the inertial navigation system. It is a set of inertial sensors, including multiple accelerometers and multiple gyroscopes, usually 3 gyroscopes and 3 accelerometers, to achieve three-dimensional ratio Measurement of force and angular rate. Regarding the technology of inertial sensors, whether they are designed with the same technology or developed according to different principles, there are several orders of magnitude differences in volume, weight, performance and cost of various inertia...

AI Technical Summary

Problems solved by technology

As mentioned earlier, the accuracy of MEMS sensors is low, especially for MEMS devices for low-cost applications, and various errors contained in them have a great impact on the accuracy of attitude measurement

On the other hand, due to the weak magnetic induction of the earth's magnetic field, the magnetometer is susceptible to interference from other magnetic fields, especially from the carrier

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