docs(readme): clarify mapping and Nav2 multi-terminal workflow

- Document per-terminal commands for Cartographer SLAM and map save path
- Document Nav2 two-terminal flow and custom map:= usage
- Warn against pasting blocking launch commands in one shell
- Fix Docker comment: compose service name is go2_sim
- Sync README_EN.md with the same structure

Made-with: Cursor

README_EN.md

@@ -48,7 +48,7 @@ The following commands cover the main Docker workflow:
 ```bash
 cd go2_sim_ws/src/docker
 docker compose up -d --build --remove-orphans        # Build containers
-docker compose up -d go2_sim                        # Start container in detached mode
+docker compose up -d go2_sim                        # Start in detached mode; go2_sim is the compose service name
 docker compose ps                                    # List containers
 docker compose exec go2_sim bash                    # Enter container
 docker compose down                                  # Remove containers
@@ -85,20 +85,71 @@ ros2 service call /robot1/robot_behavior_command quadropted_msgs/srv/RobotBehavi
 ```
 
 ## 2.3 Mapping and Navigation
-For mapping, run the following commands in terminal:
+
+**Multiple terminals are required.** `ros2 launch ...` blocks the shell until you stop it with Ctrl+C. For mapping you must run **Gazebo, Cartographer, and teleop** at the same time, so use **separate terminals** (or tmux/screen panes). **Do not** paste all commands into one terminal in sequence—the first `launch` will block and the rest will never run.
+
+**In every new terminal**, load the workspace:
+
+```bash
+cd go2_sim_ws
+source install/setup.bash
+```
+
+### Mapping (Cartographer SLAM)
+
+1. **Terminal 1 — Gazebo** (extended sensors, warehouse world):
+
 ```bash
 ros2 launch gazebo_sim launch.py sensors:=true world:=warehouse.sdf
-ros2 launch cartographer go2_cartographer.launch.py
-ros2 run teleop_twist_keyboard teleop_twist_keyboard --ros-args -r /cmd_vel:=/robot1/cmd_vel # keyboard control
-ros2 run nav2_map_server map_saver_cli -t map -f warehouse_map # save map
 ```
 
+2. **Terminal 2 — Cartographer + RViz**:
+
+```bash
+ros2 launch cartographer go2_cartographer.launch.py
+```
+
+3. **Terminal 3 — Keyboard teleop (strongly recommended)** so the robot explores; otherwise the map will stay poor or incomplete.
+
+```bash
+ros2 run teleop_twist_keyboard teleop_twist_keyboard --ros-args -r /cmd_vel:=/robot1/cmd_vel
+```
+
+4. **Terminal 4 — Save the occupancy grid** (run when you are happy with the map; writes `warehouse_map.yaml` and `warehouse_map.pgm` in the **current directory**):
+
+```bash
+cd go2_sim_ws
+source install/setup.bash
+mkdir -p maps_out && cd maps_out
+ros2 run nav2_map_server map_saver_cli -t map -f warehouse_map
+```
+
+If you open a fresh terminal elsewhere, `cd` into `go2_sim_ws`, `source install/setup.bash`, then `cd` to the save directory and run `map_saver_cli`. For Nav2, pass the **absolute path** to `warehouse_map.yaml` as `map:=` (from `maps_out`, run `realpath warehouse_map.yaml`).
+
 ![alt text](images/image-21.png)
 
-For navigation, run:
+### Navigation (Nav2)
+
+When using the bundled warehouse map, keep the same world as for mapping (`warehouse.sdf`).
+
+1. **Terminal 1 — Gazebo**:
+
 ```bash
 ros2 launch gazebo_sim launch.py sensors:=true world:=warehouse.sdf
+```
+
+2. **Terminal 2 — Nav2** (default map: installed `navigation2/maps/warehouse_map.yaml`):
+
+```bash
 ros2 launch navigation2 go2_navigation2.launch.py
 ```
 
+To use a map you saved yourself:
+
+```bash
+ros2 launch navigation2 go2_navigation2.launch.py map:=/absolute/path/to/go2_sim_ws/maps_out/warehouse_map.yaml
+```
+
+Set the initial pose and goal in RViz; Nav2 plans and executes—keyboard teleop is not required as the primary interface.
+
 ![alt text](images/image-22.png)