A control device is provided to more quickly and efficiently verify which item has been grasped by a robot system whilst also providing a solution which is scalable. Verification of the item which has been grasped is achieved by measuring a dynamics property of the item. A control unit for operation with a robot system a sensor unit, the robot system arranged to grasp an item from a container. The control unit includes a verification unit arranged to receive identifying information of an item expected to be in the container, receive information from the sensor unit indicative of a dynamics property of the item grasped by the robot system and verify that the item grasped by the robot system matches the item expected to be in the container based on the received identifying information and the received dynamics property information.