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With an increased use of composite materials within the aerospace industry follows a need for rational and cost-effective methods for composite manufacturing. Manual operations are still common for low to medium manufacturing volumes and complex products. Manual operations can for example be found in material handling, when picking prepreg plies from a cutter table and stacking them to form a plane laminate in preparation for a subsequent forming operation. Stacking operations of this kind often involves a great number of different ply geometries and removal of backing paper and other protecting materials like plastic. In this paper two different demonstrator cells for automated picking of prepreg plies and stacking of plane laminates are presented. One demonstrator is utilizing a standard industrial robot and an advanced end-effector to handle the ply variants. The other demonstrator is using a dual arm robot which allow for simpler end-effector design.

Automation in aerospace industry is often in the form of dedicated solutions and focused on processes like drilling, riveting etc. The common industrial robot has due to limitations in positional accuracy and stiffness often been unsuitable for aerospace manufacturing. One major cost driver in aircraft manufacturing is manual assembly and the bespoke tooling needed. Assembly tasks frequently involve setting relations between parts rather than a global need for accuracy. This makes assembly a suitable process for the use of force control. With force control a robot equipped with needed software and hardware, searches for desired force rather than for a position. To test the usefulness of force control for aircraft assembly an experimental case aligning a compliant rib to multiple surfaces was designed and executed. The system used consisted of a standard ABB robot and an open controller and the assembly sequence was made up of several steps in order to achieve final position.

Variability in composite manufacture and the limitations in positional accuracy of common industrial robots have hampered automation of assembly tasks within aircraft manufacturing. One way to handle geometry variations and robot compliancy is to use force control. Force control technology utilizes a sensor mounted on the robot to feedback force data to the controller system so instead of being position driven, i.e. programmed to achieve a certain position with the tool, the robot can be programmed to achieve a certain force. This paper presents an experimental case where a compliant rib is aligned to multiple surfaces using force feedback and an industrial robot system from ABB. Two types of ribs where used, one full size carbon fiber rib, and one smaller metal replica for evaluation purposes. The alignment sequence consisted of several iterative steps and a search procedure was implemented within the robot control system.