Inertial and magnetometer combination adaptive anti-interference method

Abstract

The invention belongs to the field of data fusion of magnetometers and inertial navigation systems and the field of adaptive Kalman filtering, and particularly relates to an inertial and magnetometercombination adaptive anti-interference method. The inertial and magnetometer combination adaptive anti-interference method comprises the steps that first, an output model of a magnetometer and a gyroscope is utilized to deduce a model for updating magnetometer output through the angular rate, then direct output of the magnetometer serves as the measurement amount to be substituted into a filter. Meanwhile, the invention designs an adaptive extension Kalman filter based on robust control. A noise variance array of measurement information is calculated according to the residual between the measurement amount and the predicted amount, and thus interference is effectively suppressed. The interference duration is judged while interference is handled; when it is judged that interference is long-time interference, through the inertial and magnetometer combination adaptive anti-interference method, a magnetic field value is extrapolated through inertial navigation at the early stage of interference, the magnetometer is quickly recalibrated, after calibration is completed, a magnetometer calibration parameter is substituted back into an anti-interference module again, and thus the long-timeanti-interference effect is ensured.

Description

technical field

[0001] The invention belongs to the field of data fusion of a magnetometer and an inertial navigation system and the field of adaptive Kalman filtering, and in particular relates to an adaptive anti-jamming method combined with an inertial and magnetometer. Background technique

[0002] With the development of MEMS, low-cost inertial navigation systems are usually integrated into a module or chip, and are widely used in indoor positioning, human motion tracking, unmanned systems, etc. However, as the cost decreases, the accuracy of the MEMS inertial navigation system also decreases, and it cannot be sensitive to the rotation of the earth, so the alignment of the MEMS inertial navigation system can only rely on other sensors. The magnetometer can use the measured magnetic field value to solve the orientation. Therefore, the combination of MEMS magnetometer and inertial navigation system is one of the commonly used integrated navigation systems. Most of the r...

Examples

Embodiment Construction

[0084] The present invention will be further described below in conjunction with the accompanying drawings.

[0085] The purpose of the present invention is to overcome the problem that the magnetometer is disturbed by the changing magnetic field during the use process after calibration, which leads to the decrease of heading accuracy, and proposes a combined anti-jamming technology based on the adaptive robust Kalman filter of the magnetometer and inertial navigation system . The method firstly analyzes the output model of the magnetometer and the output model of the gyroscope, and uses the two models to derive a model that uses the angular rate to update the magnetic field component. Then the model is used as the state transition model of the filter, the magnetic field component is used as the state quantity, and the output of the magnetometer is used as the quantity measurement. Since there is random error interference in the output of the magnetometer, the residual error ...

technical field

[0001] The invention belongs to the field of data fusion of a magnetometer and an inertial navigation system and the field of adaptive Kalman filtering, and in particular relates to an adaptive anti-jamming method combined with an inertial and magnetometer. Background technique

[0002] With the development of MEMS, low-cost inertial navigation systems are usually integrated into a module or chip, and are widely used in indoor positioning, human motion tracking, unmanned systems, etc. However, as the cost decreases, the accuracy of the MEMS inertial navigation system also decreases, and it cannot be sensitive to the rotation of the earth, so the alignment of the MEMS inertial navigation system can only rely on other sensors. The magnetometer can use the measured magnetic field value to solve the orientation. Therefore, the combination of MEMS magnetometer and inertial navigation system is one of the commonly used integrated navigation systems. Most of the r...

Examples

Embodiment Construction

[0084] The present invention will be further described below in conjunction with the accompanying drawings.

[0085] The purpose of the present invention is to overcome the problem that the magnetometer is disturbed by the changing magnetic field during the use process after calibration, which leads to the decrease of heading accuracy, and proposes a combined anti-jamming technology based on the adaptive robust Kalman filter of the magnetometer and inertial navigation system . The method firstly analyzes the output model of the magnetometer and the output model of the gyroscope, and uses the two models to derive a model that uses the angular rate to update the magnetic field component. Then the model is used as the state transition model of the filter, the magnetic field component is used as the state quantity, and the output of the magnetometer is used as the quantity measurement. Since there is random error interference in the output of the magnetometer, the residual error ...

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