Patent ID: 7397539

Claim:
A transfer apparatus for transferring an object, comprising: a gripper for at least one of (a) gripping the object at a first position and releasing said object at a second position proximate to a receiver and (b) releasing said object at a first position after gripping said object at a second position proximate to said receiver; a measurement device, separate and displaced from said gripper, configured to measure a relative position of said gripper with respect to said receiver in at least one direction, wherein a relative position error is determined with respect to a desired relative position of said gripper with respect to said receiver, the determination based on the measured relative position of said gripper with respect to said receiver, and the relative position of the gripper with respect to said receiver is adjusted based on the reduction of the relative position error at the second position and a difference in relative velocity or acceleration between said gripper and said receiver is minimized.