HKUST-Aerial-Robotics / VINS-Mono

A Robust and Versatile Monocular Visual-Inertial State Estimator
GNU General Public License v3.0
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IMU-preintegration linearized bias updates in integretation_base.h #339

Open sviisc opened 4 years ago

sviisc commented 4 years ago

Hi, I am trying to understand pre-integration concept implemented by VINS. I have a question regarding linearized_ba and linearized_bg in https://github.com/HKUST-Aerial-Robotics/VINS-Mono/blob/dc62ec4cfdb9c420c729524c86a32de4e6759088/vins_estimator/src/factor/integration_base.h. I am not able to see how these two variables are getting updated. After being initialized during new instance of class, in all other functions of this class, their value look to be copied from initial value. I am also unable to see how jacobian and covariance are being used in order to update linearized bias values. Am I missing something in understanding? I have also gone through #335 but it did not help in my understanding.