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--- tutorials:intermediate:simple_mobile_manipulation_plan [2019/08/02 13:19] – Added details about the reachability costmap in the end amar
+++ tutorials:intermediate:simple_mobile_manipulation_plan [2019/08/02 14:31] – [Some Useful Designators] Added more information about the object designator amar
@@ Line 42: / Line 42: @@
       * <code lisp> (desig:a motion (type going) (target ?loc-desig)) </code> is a motion that moves the body of the robot and expects a key ''target'', whose value should be of type ''location-designator''.
       * <code lisp> (desig:a motion (type looking) (target ?loc-desig))</code> is a motion that moves the head of the robot to look at the specfied location. It expects a key ''target'' with value of type ''location'' designator.
-      * <code lisp> (desig:a motion (type detecting) (object ?obj-desig)) </code> is a a motion that perceives and detects the specified object. It expects a key ''object'' with a value of type ''object-designator''
+      * <code lisp> (desig:a motion (type detecting) (object ?obj-desig)) </code> is a a motion that perceives and detects the specified object. It expects a key ''object'' with a value of type ''object-designator''. An example is <code lisp>
+      (desig:a motion (type detecting) (desig:an object (type bowl))) </code>. This motion perceives and tries to find an object of type bowl in the field of view where the camera of the robot is pointed to. The resultant of this is also an object designator, but it has much more information. A sample is given below <code lisp>
+    #<A OBJECT
+    (TYPE BOWL)
+    (NAME BOWL-1)
+    (POSE ((:POSE
+            #<CL-TRANSFORMS-STAMPED:POSE-STAMPED
+   FRAME-ID: "base_footprint", STAMP: 1.564755796743144d9
+   #<3D-VECTOR (0.7672472770564228d0 -0.35741216776250767d0 0.888642116546631d0)>
+   #<QUATERNION (-0.005783746257358676d0 -0.0013544535828327665d0 -0.26923602469246516d0 0.9630558655492675d0)>>)
+           (:TRANSFORM
+            #<CL-TRANSFORMS-STAMPED:TRANSFORM-STAMPED
+   FRAME-ID: "base_footprint", CHILD-FRAME-ID: "bowl_1", STAMP: 1.564755796743144d9
+   #<3D-VECTOR (0.7672472770564228d0 -0.35741216776250767d0 0.888642116546631d0)>
+   #<QUATERNION (-0.005783746257358676d0 -0.0013544535828327665d0 -0.26923602469246516d0 0.9630558655492675d0)>>)
+           (:POSE-IN-MAP
+            #<CL-TRANSFORMS-STAMPED:POSE-STAMPED
+   FRAME-ID: "map", STAMP: 1.564755796743144d9
+   #<3D-VECTOR (1.5255411783854167d0 0.761638069152832d0 0.8886421203613282d0)>
+   #<QUATERNION (-0.005410938989371061d0 -0.0024511234369128942d0 -0.07722260057926178d0 0.9969961643218994d0)>>)
+           (:TRANSFORM-IN-MAP
+            #<CL-TRANSFORMS-STAMPED:TRANSFORM-STAMPED
+   FRAME-ID: "map", CHILD-FRAME-ID: "bowl_1", STAMP: 1.564755796743144d9
+   #<3D-VECTOR (1.5255411783854167d0 0.761638069152832d0 0.8886421203613282d0)>
+   #<QUATERNION (-0.005410938989371061d0 -0.0024511234369128942d0 -0.07722260057926178d0 0.9969961643218994d0)>>)))> </code> Note that this resulting object designator has the name of the object along with the coordinate of the object w.r.t the robot coordinate frame and other useful coordinate transformations which can later be used to calculate the pose of the end effector for grasping.
     * **Action Designators** - These describe the high-level actions which may consist of multiple calls to different low-level motion to carry out a small plan.
         * <code lisp> (desig:an action (type picking-up) (arm ?grasp-arm) (grasp ?grasp-pose-identifier) (object ?obj-desig)) </code> is an action that picks an object with the specified arm and grasp pose. It expects an ''object'' key with value of type ''object-designator'', an ''arm'' with the value of type keyword for the arm to choose, and a ''grasp'' key whose value specifies a keyword which is an identifier of the grasp pose to pick the object with.
@@ Line 360: / Line 384: @@
                                (object ?perceived-bottle)))
 </code>
 We see that the robot defaults the right arm when the object is in the center and will always try to grasp the left side of the bottle, even when the object is slightly favoring the left side under it (Refer the figure below).
+Note: ''We have been using left-side here a lot. In the context of (grasp left-side), it refers to the left-side of the bottle. But what defines the "left-side"?''
+''Before we understand it, we have to acknowledge that every object spawned in the bullet world has its own coordinate axes - even rotationally symmetric objects like the bottle here. And the definition for left-side is the side of the -ve Y-axis in the bottle coordinate frame. Similarly right-side is +ve Y-axis, front is denoted by +ve X-axis and the back by -ve X-axis. ''
+''With this the "left-side" grasp can change based on how the object is oriented in the world. But it remains the w.r.t the object coordinate frame.''
+''The file at <your workspace>/cram/cram_common/cram_object_knowledge/src/household.lisp holds some definitions for grasps supported by the household objects supporte in CRAM.''
 {{:tutorials:intermediate:btw-tut-grasp-config-fail.png?800|}}