A robot has a gripper for gripping parts and releasing the gripped part at a destination position. The gripped part is vibrated at the destination position to cause the gripper to release the gripped part. The gripped part can be directly vibrated or vibrated by vibrating the mechanical structure of the gripper or by vibrating air in the gripper mechanical structure. The vibrator can connect the gripper to the robot. The vibrator can be inside or attached to the one or more of the articulated fingers of the gripper. The vibrations can be stopped when a sensor detects that the gripped part has been released or after the passage of a preset vibration time.