Action to move robot to some pose from which an object can be picked up

[mpomarlan]

What does NOT, in general, work: going to a location described by (desig:a location (reachable-for pr2) (arm ?arm) (location '(some description of the location of an object or the pose of the object))

Why it doesn't work: unless the object is small, there may be a significant distance between its center (which is, its pose) and the pose of whatever handles the object has. Further, the way in which these handles may be graspable may have a different orientation than the object pose itself.

Example: the center of a tray is not reachable for the gripper aligned to the object orientation, but a side handle is reachable from the top with the gripper pointing down.

Apparent alternatives: (to see) seems to have been intended as this, and there may be an (obj) location designator keyword for the same purpose. I didn't get these to work however.

Suggested fix: have a way to list all possible (arm grasp) pairs for an object. This is enough to query object-to-gripper transforms, therefore to get a set of poses for the robot to try to reach.