Update composite_controller.py (#700)

* Update composite_controller.py

Explain what `get_controller_base_pose` does

* Update composite_controller.py

Update docstring

* Update composite_controller.py

Update docstring

* Format

Author: kevin-thankyou-lin

robosuite/controllers/composite/composite_controller.py

@@ -122,6 +122,23 @@ def get_control_dim(self, part_name):
             return self.part_controllers[part_name].control_dim
 
     def get_controller_base_pose(self, controller_name):
+        """
+        Get the base position and orientation of a specified controller's part. Note: this pose may likely differ from
+        the robot base's pose.
+
+        Args:
+            controller_name (str): The name of the controller, used to look up part-specific information.
+
+        Returns:
+            tuple[np.ndarray, np.ndarray]: A tuple containing:
+                - base_pos (np.ndarray): The 3D position of the part's center in world coordinates (shape: (3,)).
+                - base_ori (np.ndarray): The 3x3 rotation matrix representing the part's orientation in world coordinates.
+
+        Details:
+            - Uses the controller's `naming_prefix` and `part_name` to construct the corresponding site name.
+            - Queries the simulation (`self.sim`) for the site's position (`site_xpos`) and orientation (`site_xmat`).
+            - The site orientation matrix is reshaped from a flat array of size 9 to a 3x3 rotation matrix.
+        """
         naming_prefix = self.part_controllers[controller_name].naming_prefix
         part_name = self.part_controllers[controller_name].part_name
         base_pos = np.array(self.sim.data.site_xpos[self.sim.model.site_name2id(f"{naming_prefix}{part_name}_center")])