Hi everyone,

I have a question about the ground truth. I have implemented navigation based on GPS and applied the robot-localisation package (https://github.com/cra-ros-pkg/robot_localization). Now I want to consider GPS data as my ground truth and compare the results of global-odometry and slam odometry with GPS odometry. but the GPS is not working properly in some parts of the environment and does not provide accurate data. now my question is that how can I define a ground truth for my system?