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Previously given Paper 09ATC-0232 delivered at the SAE Aerotech conference in Seattle in 2009 reports on the E6000 machine installing slug rivets with the EMR. Paper 2015-01-2491given at the SAE conference in Seattle in 2015 reports on index head rivets being installed with screw driven squeeze process. This paper reports on the screw driven squeeze process installing unheaded slug rivet which is a more complex process. We also report on improvements to the fixture automation.

There exists a demand in the aerospace industry for highly configurable and flexible automated riveting cells to manufacture small to medium sized panels of complex geometries. To meet this demand Electroimpact has developed a manufacturing system consisting of a stationary Electro-squeeze C-frame riveter, coupled with a robot part positioner to present the component to the process head tool point. The C-frame can install a wide range of aerospace rivets and perform specialist functions including backside countersinking operations, giving potential for double flush fastening. The geometric limitations and high implementation costs of large cartesian based positioning barges or fixed jig tooling and moving gantry riveters are avoided when exchanged for a robot part positioner.

The use of a narrow profile posts or Skinny Fixture increases build speed and flexibility while improving quality of aluminum aircraft panels fastened in one-up assembly cells. Aluminum aircraft panels are made up of an outer skin and a series of stringers. The components must be held in accurate relative positions while preliminary fasteners are installed. By using narrow fixture posts in conjunction with deep drop stringer side machine tools, the fastening machine can apply fasteners at tighter initial spacing. The spacing is gained by providing clearances that allows the centerline of the fastening system to work closer to the post than previously achieved with deep fixture posts and short stringer side tooling. At one time the standard process was to hold the parts in manual tack cells and after tacking the panels are moved to a separate automated fastening cell. One-up assembly fixtures improve the process by reducing manual processes while minimizing component handling.

The Boeing 787 Dreamliner will be the most fuel-efficient airliner in the world when it enters service in 2008. To help achieve this, Boeing will utilize state-of-the-art carbon fiber for primary structures. Advanced manufacturing techniques and processes will be used in the assembly of large composite structures. Electroimpact has proposed a system utilizing the low recoil Low Voltage Electromagnetic Riveter (LVER) to drill and install bolts. A test program was initiated between Boeing Materials Process and Engineering (MP&E) and Electroimpact to validate the LVER process for swaging titanium collars on titanium pins in composite material. This paper details the results of these tests.

The A380 aircraft is the largest passenger aircraft ever built and an appropriate machine was required to accomplish the fastening of the wing plank to stringer and buttstrap joints. The lower wing panels are curved along the length and move 1.42m out of plane. All previous E4000 machines had clampup heads that would extend and retract whatever distance was required to contact the wing panel. To improve toolpoint alignment, Electroimpact added a Z-axis that moves the yoke in order to reduce the necessary travel envelope of the clamp table axes and to cause them to clamp in the same plane regardless of panel position along the Z-axis.

Northrop Corporation manufactures body panels for the Boeing 747 aircraft. There are 1259 different stringer configurations used on the three 747 models with an average of 839 stringers per ship set. Until recently, all drain holes and skin coordination pilot holes were drilled manually using plastic application template tools (PATTS). Inventory costs were high and manual drilling errors led to excessive scrap and rework rates. Northrop engineers recognized that automating the stringer drilling process would produce higher quality parts at a lower cost. Northrop worked with Electroimpact, Inc. to develop the Automatic Stringer Drilling System (ASDS). The ASDS automatically clamps and drills all straight and contoured stringers used on the 747. Stringers are mounted on a rotating platform that provides +/- 90° of motion. Two servo-servo drills are mounted on a cantilevered arm with 25 feet of X-axis travel.

New EMR technologies have been developed in response to customer demand for better process control and reliability. In hand riveting of large panels visual contact between operators is blocked. A reliable means was required to insure that guns could only discharge when properly deployed upon opposing ends of the rivet. A second problem is to satisfy the demand for improved process control in EMR operation. These goals were achieved by implementing a fully digital control scheme for the EMR operation. These new technologies are covered in this paper.