implementing SLAM while using GPS map

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Thanks a lot, I know about this robot_localization pkg. I want to do autonomous mapping and navigation at the same time based on GPS. I want to do outdoor navigation.

Now I am confused that how is it possible to merge SLAM (for instance rtabmap), with robot_localization pkg which create map->odom and odom-> base_link.

It seems that if I use robot_localization pkg, it is not possible to use SLAM and mapping part is not autonomous.

robot_localization is a poor name - it doesn't do "localization" in the classical sense of SLAM. It really is just an EKF/UKF implementation that helps you fuse sensors (odometry, IMU, GPS) to get the base_link -> odometry transform. The odometry -> map transform is what SLAM gives you.

for navigation based on GPS, it necessitates to implement robot_localization pkg two time, once for the fusion of imu and wheel odometer, which provides odom-> base_link frame, and in the other implementation for the fusion of Imu, wheel odometer, and GPS, which provides map->odom frame. so in this case when all the frames have been created it seems we cannot use SLAM(at least i don't know). now my question is that: Is it possible to do autonomous mapping and navigation based on GPS? if yes, for the mapping part am I able to use Rtabmap or any other kind of SLAM?

let me ask another question, I have seen in some of the works they applied robot_localization packages (two instances), and gmapping. how is it possible to use gmapping and use robot_localization pakage which has created all the frames! (map > odom and odom> base-link)

I have the same problem. Did you solve it?