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--- doc:srdl2_tutorial [2014/11/27 16:52] – [Requirements of an action] admin
+++ doc:srdl2_tutorial [2014/11/27 17:05] (current) – [Matching requirements to capabilities] admin
@@ Line 28: / Line 28: @@
 $ rosrun rosprolog rosprolog knowrob_srdl
-% Load SRDL model of the PR2 robot
+% Load SRDL model of the PR2 and Baxter robots
 ?- owl_parse('package://knowrob_srdl/owl/PR2.owl').
+?- owl_parse('package://knowrob_srdl/owl/baxter.owl').
 % Load an example task description for serving a drink
@@ Line 120: / Line 121: @@
 ===== Missing components or capabilities =====
-  ?- missing_cap_for_action(tablesetting:'TableSetting', tumrosie:'TUM_Rosie1', Cap).
+<code prolog>
-  Cap = 'http://ias.cs.tum.edu/kb/srdl2-cap.owl#PuttingDownAnObjectCapability' ;
+% No components nor capabilities are missing for the ServeADrink action on the PR2:
-  Cap = 'http://ias.cs.tum.edu/kb/srdl2-cap.owl#PickingUpAnObjectCapability' ;
+?- missing_comp_for_action(serve_drink:'ServeADrink', pr2:'PR2Robot1', C).
+false.
-  ?- missing_comp_for_action(tablesetting:'TableSetting', tumrosie:'TUM_Rosie1', Comp).
+?- missing_cap_for_action(serve_drink:'ServeADrink', pr2:'PR2Robot1', C).
-  false.
+false.
+% The Baxter robot, in contrast, cannot perform the task due to lacking navigation abilities:
-===== Matching requirements to capabilities =====
+?- missing_cap_for_action(serve_drink:'ServeADrink', baxter:baxter_baxter1, C).
+C = srdl2cap:'BaseMotionCapability'
+</code>
+===== Behind the scenes: Implementation of the matching procedures =====
 The matching can effectively reduced to the following statement:
+<code prolog>
   missing_cap_for_action(Action, Robot, Cap) :-
      required_cap_for_action(Action, Cap),
      \+ cap_available_on_robot(Cap, Robot).
-A missing capability is thus defined as one that is required by an action, but not provided by the robot. Required means that either the action itself or any sub-action has a dependency on this capability:
+</code>
+A missing capability is thus defined as one that is required by an action but not provided by the robot. "Required" thereby means that either the action itself or any sub-action has a dependency on this capability:
+<code prolog>
   required_cap_for_action(Action, Cap) :-
      class_properties(Action, srdl2cap:'dependsOnCapability', Cap).
@@ Line 140: / Line 149: @@
      plan_subevents_recursive(Action, SubAction),
      class_properties(SubAction, srdl2cap:'dependsOnCapability', Cap).
+</code>
-There are three possibilities to express that a capability is available on a robot: Either it is asserted to be available for the whole class of robots (e.g. every PR2 has a holonomic base), for a specific robot instance, or it can be concluded that the capability should be available because all specified dependencies on components or other capabilities are fulfilled:
+There are three possibilities to express that a capability is available on a robot: Either it is asserted to be available for the whole class of robots (e.g. every PR2 has a mobile base), for a specific robot instance, or it can be concluded that the capability should be available because all specified dependencies on components or other capabilities are fulfilled:
+<code prolog>
   % capability asserted for robot instance
   cap_available_on_robot(Cap, Robot) :-
@@ Line 162: / Line 173: @@
      forall( class_properties(Cap, srdl2cap:'dependsOnCapability', SubCap),
              cap_available_on_robot(SubCap, Robot) ).
+</code>
 The matching procedure is equivalent for components.