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3.
Manipulation
3.6 Controlling the base
The system described so far can retrieve cans from a wide range
of heights and at a variety of distances from the robot's body.
However, the arm operates only in a single vertical plane. For
successful operation the can must be aligned with this plane to
within the tolerance of the gripper (about
0.75"
either
way).
The
final level of the arm controller, Swivel, loosens this restriction
by using information from the hand IRs to turn the entire robot
and help center the can. As shown back in figure 3-5, the hand's
crossed infrared sensors respond over a region nearly three
times the width of the "gra ...