Chapter 7, Interfacing Vision Sensors with ROS

1. Most of the 3D depth sensors have additional vision sensors to detect the depth. It may be using IR projection method or using stereo vision.
2. The message passing interface, tools to visualize and debug robots, off-the-shelf robot algorithms.
3. OpenCV is mainly having computer vision algorithm, OpenNI is having algorithm implementation for implementing NI applications, and PCL is having algorithm to process point cloud data.

4. It stands for Simultaneous Localization and Mapping. It is an algorithm commonly used to map the robot environment and localize on it at the same time.
5. It is an algorithm to map the robot environment in 3D.