My project consist to build a 3D map with RGB-D SLAM, i worked with microsoft kinect and turtlebot2 (hydro distro) i want to know if i can do this task with RTAB-Map and also to understand the difference between RTAB-Map package and RGB-D SLAM v2 package and what launch does make the 3D mapping!
I'll try to answer this question, but I'm not very familiar with the RGB-D SLAM v2 package. The GUI and the results are somewhat similar to RTAB-Map. So with both, you can get a 3D point cloud of the environment with only a Kinect.
What is the goal of creating a 3D map in your project? Will it be used for robot navigation? or robot teleoperation? or just for visualization? Well, if it is just for visualization, you don't need a robot at all, just use a hand-held Kinect and compare the results between RGB-D SLAM v2 and RTAB-Map:
(Don't launch them at the same time!)
RGB-D SLAM v2:
$ roslaunch rgbdslam openni+rgbdslam.launch
$ roslaunch freenect_launch freenect.launch depth_registration:=true
$ roslaunch rtabmap rgbd_mapping.launch
For navigation in a 3D map, you will need an octomap. Octomap seems more integrated in RGB-D SLAM v2 than in RTAB-Map. However, RTAB-Map generates a 3D point cloud, this point cloud can be converted to an octomap like in this post.