I have a question related to the state vector of robot_localization package.

I am trying to get a localization system working based on IMU and an absolute position sensor in 3D. It turns out that without any velocity measuremetns, I end up with non-zero velocity while having stabilized position (which is not the correct one in the end). This is likely caused by the bias of accelerometer, which is around 20 mg.

I think, that it should help to have "accelerometer bias" in the state vector of robot_localization and let EKF estimate it as well.

I found two questions related to this:

1. https://answers.ros.org/question/271566/robot_localization-enhance-local-positioning-with-imu/ , where Tom Moore writes: > I have yet to add acceleration bias correction for the IMU data
2. https://answers.ros.org/question/284325/imu_gps-robot_localization-and-navsat_transform_node/ , where he states that: > The filter does not have active bias correction, so unless you have a velocity reference (e.g., wheel encoder or visual odometry), the integration of acceleration data will cause your state estimate to start running away rapidly.

I am about to start implementing the bias estimation into EKF. I wanted to ask -- what is the reason for not having accelerometer bias in the state vector of robot_localization package?