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Hello, currently i'm using an EKF from the robot localization package to generate the odom->base_link transformation. For this, i'm using three sources: wheels velocities, laser and visual. Since visual and laser approaches rely heavily on features my approach was to derive instantaneous velocities from two consecutive measurements in time (yea i know they can be noisy).

In this EKF i'm only using velocities so i don't have any reference for position, thus it seems like that my filter covariances for a two d mode starts to grow slowly for position (velocities are fine).

Besides all this, i never have jumps or nothing on my global EKF which takes this velocities from the first ekf and fuse them with a global estimator such as AMCL.

My questions are:

  • can the parameter dynamic process covariance help me in this case? Or
  • since i'm not relying on the state prediction (not feeding any dynamics to the my prediction stage) is generating this behaviors?
  • Or is just some issue with the integration from velocities to position?

I'm still very new on using and tuning Kalman Filters ;)

Thank you in advance.

Originally posted by tiagojdias on ROS Answers with karma: 16 on 2019-05-28

Post score: 0

Original comments

Comment by Tom Moore on 2019-06-06:
I'm not clear what the actual issue is. Are you trying to get the state estimate to jump/correct when you fuse it with AMCL data?

In any case, I can't comment at all unless you provide your full EKF configurations, as well as a sample sensor message for each sensor input.

I will say that you should not be fusing the output of one EKF into the second. Just fuse the same input sources in both.

Comment by Tom Moore on 2019-08-22:
Any update on this? If not, may I close the question?


1 Answer 1


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You can close the issue.

I was able to solve the problem after some tune on each sensor covariance.

Originally posted by tiagojdias with karma: 16 on 2019-08-25

This answer was ACCEPTED on the original site

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