How Do Robots Know Where To Go

Map
Robots need to be aware of the structure of their environment. For this, they first require a map. This is typically achieved through SLAM (Simultaneous Localization and Mapping) technology. SLAM allows the robot to move within an unknown environment while constructing a map and locating itself within it.。

Localization
Once the robot has a map, the next step is to determine its position on the map. This is accomplished using various sensors, such as LIDAR, gyroscopes, and wheel encoders. Localization algorithms fuse this sensor data, match it with the map, and ascertain the robot's exact position.。

Planning
Once the robot has its location on the map, we select a target point from the map and notify move_base, which is a key package within the ROS navigation stack, responsible for bridging localization and path planning. move_base combines global and local path planning. Global planners, such as navfn or global_planner, are used to generate the optimal path from the robot's current position to the target location based on the known map. This often involves graph search algorithms like A* or Dijkstra. Local planners, such as dwa_local_planner or teb_local_planner, are used to dynamically plan the path as the robot proceeds along the global route, avoiding obstacles or other unknown factors in real-time

4. Navigation Completed
Once the robot has planned its global route to the target point and has executed the motion planning, it checks by comparing the commanded target coordinates with the robot's current localization coordinates. If the error is within an acceptable range, it is determined that the destination has been reached.