
3.5 Controlling the arm globally
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will bounce backward along the table until it reaches the edge
and then proceed straight home. If the robot is grasping some-
thing, however, the hand will jam it against the table top causing
the DEPOSIT and UNCRASH behaviors to release the object.
The "up then back" strategy used by HOIST eliminates this
difficulty. Yet HOIST does not completely subsume HOME;
once the hand leaves the workspace HOIST no longer generates
any outputs and allows HOME to finish retracting the arm. This
is another case where a more specific behavior (HOIST)
suppresses a general purpose behavior (HOME).
The other behavior in this ...