Patent ID: 8226142

Claim:
A workpiece detection system, comprising: a gripper arm assembly comprising a first gripper member, wherein the gripper arm assembly is configured to selectively grip a workpiece between the first gripper member and one or more second gripper members via a selective contact of a dielectric layer of the first gripper member with a peripheral edge of the workpiece; an electrode operably coupled to the first gripper member; an integrated circuit configured to detect a change in capacitance between the electrode and ground based on a grip condition of the gripper arm assembly, wherein the grip condition is associated with the first gripper member contacting the workpiece; and a voltage source operably coupled to the electrode, wherein the dielectric layer of the first gripper member is configured to store an electric charge, and wherein the integrated circuit is further configured to detect a change in the electric charge between the electrode and the workpiece, wherein the change in charge is based on the first gripper member contacting the workpiece.