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Difference between state estimate data and odometry data

asked 2015-09-26 11:12:09 -0600

boon gravatar image

updated 2015-09-26 11:18:59 -0600

I am trying my hand at robot navigation. I am not able to comprehend, the following differences,

  1. Difference in the odometry data from sources like wheel or visual and the output generated by state estimators like robot_pose_ekf packages. Because they both seem to have the same message format.

  2. I am able to understand the transform between baselink and different sensor coordinate frames. But what is the difference between world, map, nav, odom and base_link frame. In some cases I find, base_footprint and base_stabilized coordinate frames too.

  3. In the tf map, should there be one fixed frame and can odom_frame be made as fixed frame in the presence of /map or /world frame?

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answered 2015-09-26 19:16:47 -0600

Naman gravatar image
  1. Data from sources like wheel encoders or visual odometry can be noisy and might not be good enough. Therefore, robot_pose_ekf combines measurements coming from different sources (like IMU, Wheel encoders, Visual Odometry) using EKF to provide a better estimate of the 3D pose of the robot.

  2. REP-105 explains different coordinate frames. base_footprint is just a projection of base_link on the ground.

  3. Yes.. odom_frame can be made a fixed frame in presence of other frames. I am not 100% sure about this. Can someone confirm this?

Hope it helps.

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Asked: 2015-09-26 11:12:09 -0600

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Last updated: Sep 26 '15