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6. Discussion
module in some sequence fails when the first module could have
succeeded. For instance, once the IR proximity detectors on the
front of the hand change from on to off, the robot has enough
information about the sensed object's position to make a ballistic
grab for it. Yet, instead, the EXTEND behavior attempts to
trigger the beam sensor between the fingers in order to initiate
grasping. However, if the finger sensor's receiver is bathed in
bright sunlight, it may not respond to the can. If there were
some medium for communication between the two processes, at
least GRAB could try to adjust its sensing threshold to com-
pensat ...