oridong
diff --git a/‎docs/source/arm.rst
Lines changed: 1 addition & 0 deletions b/‎docs/source/arm.rst
Lines changed: 1 addition & 0 deletions
diff --git a/‎docs/source/arm_superclass.rst
Lines changed: 34 additions & 0 deletions b/‎docs/source/arm_superclass.rst
Lines changed: 34 additions & 0 deletions
diff --git a/‎roboticstoolbox/robot/DHLink.py
Lines changed: 4 additions & 3 deletions b/‎roboticstoolbox/robot/DHLink.py
Lines changed: 4 additions & 3 deletions
@@ -8,5 +8,6 @@ Manipulator arms
    arm_dh
    arm_ets
    arm_urdf
+   arm_superclass
    arm_backend
    arm_trajectory
@@ -0,0 +1,34 @@
+Superclasses
+============
+
+
+Robot
+-------
+
+.. inheritance-diagram:: roboticstoolbox.ERobot
+   :top-classes: roboticstoolbox.Robot
+   :parts: 2
+
+The various models :ref:`E Models` all subclass this class.
+
+.. automodule:: roboticstoolbox.robot.Robot
+   :members:
+   :undoc-members:
+   :show-inheritance:
+   :inherited-members:
+   :special-members: __getitem__
+   
+Link
+-------
+
+The ``ERobot`` is defined by a tree of ``ELink`` subclass objects.
+
+.. inheritance-diagram:: roboticstoolbox.Link
+   :top-classes: roboticstoolbox.robot.Link
+   :parts: 2
+
+.. automodule:: roboticstoolbox.robot.Link
+   :members:
+   :undoc-members:
+   :show-inheritance:
+   :inherited-members:
@@ -41,9 +41,10 @@ def _sin(theta):
 
 class DHLink(Link):
     """
-    A link superclass for all link types. A Link object holds all information
-    related to a robot joint and link such as kinematics parameters,
-    rigid-body inertial parameters, motor and transmission parameters.
+    A link superclass for all robots defined using Denavit-Hartenberg notation.
+    A Link object holds all information related to a robot joint and link such
+    as kinematics parameters, rigid-body inertial parameters, motor and
+    transmission parameters.
 
     :param theta: kinematic: joint angle
     :type theta: float