An RGB-D sensor, like the Orbbec Astra or Microsoft Kinect, houses a color camera (RGB) along with a depth camera (D). Using the depth sensor, we can map the color image on top of the depth image to get a 3D color image.
RTABMAP (Real-Time Appearance-Based Mapping) is a RGB-D Graph-Based SLAM approach based on an incremental appearance-based global Bayesian loop closure detector.
RGBDSLAM is a RGB-D loop-closure graph-based SLAM approach using visual odometry and custom implementations of opencv methods
ORB_SLAM is a