how gmapping gather odom data?

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Hi, If my understanding is correct, The Odometry information and TF transform are two things. The TF transform stands for the transforms between two frames (like the transforms between two rigids). The odometry information records the wheel data, like how long the robot has gone.

Why gmapping receive the odom information from /tf instead of from /odom?

Thankyou

TF is a standard used by the TF toolset (which you should look up its wiki page if you don't know it) for time variant transformations. This gives it an interpolated, high-quality estimate of the odometry vs just taking the last message from a single source.

TF transformation will provide a very similar thing to the odometry message, but they are used for different purposes.

Thank you. I found the TF tutorial on the wiki. Got a better though after running the tutorial.