Ground truth from the jackal robot

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Shouldn't this be possible by using the tf library in ROS without a plugin as described in their tf tutorials? I am a little confused about the transformation between frames. For the real pose of the robot which frames should we be transforming between?

Normally in a scenario with localization you have at least two frames that are the map and base_link frame and if you are using odometry i have the odom frame as well. The map frame is fixed in the world and the base_link is fixed to your robot. Read the next comment please

What you want is the real pose of the robot that gazebo can give you. That being said, the position that the robot think it is is given by the transform between the map and the base_link frame.

Hi jbga, Thanks for your answer. The jackal does not have a map frame. It has a odom frame and a chassis_link frame. I think, I need to replace the map frame with the odom frame. How will this work on the real jackal?

Let me explain the process: Normally the map frame appear when you have a localization node like amcl that publishes a transform from the map frame to the odom frame. The odom frame is typically created by the node that publish the odometry. Next comment please

This odometry node publish the transform between the odom frame and the chassis_link as well. So, from what you said i think that you need a localization node as well as a map. Think about it before pass the code to the real robot. Any doubt just ask

Hi Jbga, I have code that runs the robot in simulation with a certain velocity. I subscribe to the odometry frame to get the odometry pose values. I want to know the position of the robot to compare with the odometry values to plot and show the shift in pose values.

The tf_echo command shows that the odom frame is the parent of the base_link frame. It says there is no map frame. So how do I get a transform? I probably need to run the jackal with gmapping.