fix: update section references to use consistent formatting (#1169)

Author: AtsushiSakai

docs/modules/1_introduction/3_technologies_for_robotics/technologies_for_robotics_main.rst

@@ -5,22 +5,54 @@ The field of robotics needs wide areas of technologies such as mechanical engine
 electrical engineering, computer science, and artificial intelligence (AI).
 This project, `PythonRobotics`, only focus on computer science and artificial intelligence.
 
+The technologies for robotics are categorized as following 3 categories:
 
+#. `Autonomous Navigation`_
+#. `Manipulation`_
+#. `Robot type specific technologies`_
+
+.. _`Autonomous Navigation`:
 
 Autonomous Navigation
 ^^^^^^^^^^^^^^^^^^^^^^^^
-
-In recent years, autonomous navigation technologies have received huge
-attention in many fields.
-Such fields include, autonomous driving[22], drone flight navigation,
-and other transportation systems.
-
-An autonomous navigation system is a system that can move to a goal over long
+Autonomous navigation is a capability that can move to a goal over long
 periods of time without any external control by an operator.
-The system requires a wide range of technologies:
+
+To achieve autonomous navigation, the robot needs to have the following technologies:
 - It needs to know where it is (localization)
 - Where it is safe (mapping)
+- Where is is safe and where the robot is in the map (Simultaneous Localization and Mapping (SLAM))
 - Where and how to move (path planning)
 - How to control its motion (path following).
 
 The autonomous system would not work correctly if any of these technologies is missing.
+
+In recent years, autonomous navigation technologies have received huge
+attention in many fields.
+For example, self-driving cars, drones, and autonomous mobile robots in indoor and outdoor environments.
+
+In this project, we provide many algorithms, sample codes,
+and documentations for autonomous navigation.
+
+#. :ref:`Localization`
+#. :ref:`Mapping`
+#. :ref:`SLAM`
+#. :ref:`Path planning`
+#. :ref:`Path tracking`
+
+
+
+.. _`Manipulation`:
+
+Manipulation
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+#. :ref:`Arm Navigation`
+
+.. _`Robot type specific technologies`:
+
+Robot type specific technologies
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+#. :ref:`Aerial Navigation`
+#. :ref:`Bipedal`

docs/modules/2_localization/localization_main.rst

@@ -1,4 +1,4 @@
-.. _localization:
+.. _`Localization`:
 
 Localization
 ============

docs/modules/3_mapping/mapping_main.rst

@@ -1,4 +1,4 @@
-.. _mapping:
+.. _`Mapping`:
 
 Mapping
 =======

docs/modules/4_slam/slam_main.rst

@@ -1,4 +1,4 @@
-.. _slam:
+.. _`SLAM`:
 
 SLAM
 ====

docs/modules/5_path_planning/path_planning_main.rst

@@ -1,4 +1,4 @@
-.. _path_planning:
+.. _`Path Planning`:
 
 Path Planning
 =============

docs/modules/6_path_tracking/path_tracking_main.rst

@@ -1,4 +1,4 @@
-.. _path_tracking:
+.. _`Path Tracking`:
 
 Path Tracking
 =============

docs/modules/7_arm_navigation/arm_navigation_main.rst

@@ -1,4 +1,4 @@
-.. _arm_navigation:
+.. _`Arm Navigation`:
 
 Arm Navigation
 ==============

docs/modules/8_aerial_navigation/aerial_navigation_main.rst

@@ -1,4 +1,4 @@
-.. _aerial_navigation:
+.. _`Aerial Navigation`:
 
 Aerial Navigation
 =================

docs/modules/9_bipedal/bipedal_main.rst

@@ -1,4 +1,4 @@
-.. _bipedal:
+.. _`Bipedal`:
 
 Bipedal
 =================