Mapping | Notion

A map is a representation of the environment where the robot is operating. It should contain enough information to accomplish a task of interest.
There are different ways to represent a map
1. Metric
  - Feature based
  - Grid based
  - Hybrid
2. Topological
3. Hybrid
In order to create a map it is necessary to merge the measurements from previous positions and also keep a track of current measurements and the pose of the bot as they are changing.
To overcome this problem we use a technique called Simultaneous Localization and Mapping(SLAM). It estimates the map of the environment and the trajectory of a moving device using a sequence of sensor measurements.
There are a lot of SLAM algorithms around. To name a few, Gmapping, Hector mapping, Cartogrpaher, Rtab mapping etc. Here is a little comparison,

Here is an example of mapping using slam-toolbox by nav2 stack, we will be learning to do it in the next section:

More About Mapping