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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.

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.

The 787 Section 11 Assembly Cell is a combination fixed post and moving frame holding and indexing system, designed to determinately build the 787 Section 11 Wing box. The retractable overhead frame allows maximum clearance for safer and faster loading and unloading of component parts, as well as completed wingbody sections. Additionally, each index is also retractable allowing maximum fastener access inside the jig.

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.

For seven years Electroimpact, Inc. has been providing manufacturing equipment to the aerospace assembly business. Our industry is not partial toward working with small companies such as Electroimpact. But we fill a niche. The niche which we fill is in the area of new processes. We have developed new processes which have made inroads into the industry. This paper will review a number of case studies for the implementation of new manufacturing technology in the aerospace industry. In all of these cases motivation for the implementation of new technology is the driving force and concurrent engineering is the vehicle for successful implementation. Although this review is only cursory it can provide a reference to help you make further inquiries.

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.

Electroimpact has retrofitted two E4100 riveting gantry machines and two more are in process. These machines use the EMR (Electromagnetic Riveter) riveting process for the installation of slug rivets. We have improved the skin side EMR to provide fast and reliable results: reliability improved by eliminating a weekly shutdown of the machine. In paper 2015-01-2515 we showed the slug rivet injector using a Synchronized Parallel Gripper that provides good results over multiple rivet diameters. This injector is mounted to the skin side EMR so that the rivet injection can be done at any position of the shuttle table. The EMR is a challenging application for the fingers due to shock and vibration. In previous designs, fingers would occasionally be thrown out of the slots. To provide reliable results we redesigned the fingers retainer to capture the finger in a slotted plastic block which slides along the outside diameter of the driver bearing.

Two spindles are discussed in this paper. The first spindle was installed on nine C-frame riveters on the 737/757 wing line at the Boeing Renton facility. Due to discontinuing the use of Freon coolant and cutting fluid, the C-frame riveters had difficulty shaving 2034 ice box rivets with the existing 6000 RPM hydraulic spindles. The solution was to install electric 30,000 RPM shave spindles inside the existing 76.2 mm (3 in.) diameter hydraulic cylinder envelope. The new spindle is capable of 4 Nm (35 in. lbs.) of torque at full speed and 110 kgf (250 lbs.) of thrust. Another design of interest is the Electroimpact Model 09 spindle which is used for 20,000 RPM drilling and shaving on wing riveting systems. The Model 09 spindle is a complete servo-servo drilling system all mounted on a common baseplate. The entire spindle and feed assembly is only 6.5″ wide.

The Electromagnetic Bolt Inserter (EMB) is a new tool that combines functions that on previous machines were performed by two tools, a bolt inserter followed by an EMR. By combining the operations of two tools in one the processing time for the wing spar is reduced. The tool incorporates quality checks for bolt length, stake height and bolt insert height.

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.

A new style of all electric riveting machine has been developed with saddle hoppers that does not require a track between the hoppers and the fingers. This enables feeding square rivets without difficulty. The upper ram has a bent knee which allows the rivet fingers to be brought up to the hopper and rotated 30 degrees rather than the rivet sliding down a track, which minimizes jamming that occurs with some fasteners in the track, and increases reliability. A mixture of fasteners can be loaded side by side in the hoppers, increasing flexibility. The rivet feeding is accomplished by bringing the rivet fingers to the hopper. The machine uses a power drawbar to change out different rivet fingers. A small industrial robot is incorporated into the machine to complete different sized coupons and also complete small assemblies. In larger machines larger robots or CNC positioners can be used to scale up the use of the machine.

A frame-clip riveting end effector has been developed for installing 3.97mm (5/32) and 4.6mm (3/16) universal head aluminum rivets. The end effector can be mounted on the end of a robot arm. The end effector provides 35.6 kNt (8000 lbs) of rivet upset. Rivets can be installed fifteen millimeters from the IML. The clearance allowed to rivet centerline is 150 millimeters. The riveting process features a unique style of rivet fingers for the universal head rivet. These fingers allow the rivet to be brought in with the ram. This differentiates from some styles of frame-clip end effectors in which the rivet is blown into the hole. The paper shows the technical components of the end effector in sequence: the pneumatic clamp, rivet insert and upset. The end effector will be used for riveting shear ties to frames on the IML of fuselage panels.

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.

This paper will cover the design of the horizontal rivet injector use on the SA2 LVER designated for stage 0 production of Airbus A320 Upper Wing Panels. The injector design is intended to decrease cycle times and increase reliability while not reducing the functionality over previous rivet feed designs used by Electroimpact. Specific rivet handling methods and design features will be reviewed and their result on cycle time and reliability discussed.

A new wing panel riveting cell capable of replacing tack fasteners and performing small repair jobs has been developed. Using two mobile scissor lift platforms with electromagnetic riveters mounted on each, the operators can access every portion of the wing panel without the use of ladders or platforms. This method minimizes fatigue, allows workers to carry all tools and supplies with them, meets current safety standards and minimizes coldworking of the components.

A simple, open, post and index system is used for final alignment and joining of the fuselage and wings of a new passenger business jet. 19 manually actuated axes precisely move the wings, forward, and rear fuselage sections into position. Movement is accomplished with industrial jacking screws and positions recorded with precision linear potentiometers. Wing sweep, angle of attack, and dihedral are monitored and controlled. The axes positions are downloaded to data files for verification and data archiving. The Gulfstream G150 Join Cell's open architecture enhances access to fasten the main aircraft structure while maintaining flight critical geometry.

The handheld (HH) electromagnetic riveter (EMR) has been proven to be an effective means of installing rivets up to 3/8″ diameter. However, early versions were heavy and cumbersome to use. A new generation of handheld riveting systems has been developed with substantially reduced weight and improved ergonomics by incorporating a spring-damper recoil reduction system. Additional improvements include a simpler and more robust control system and a 0-1000V voltage range to improve efficiency.

There is an ever-present risk for the lower ram on a riveting machine to suffer a damaging collision with aircraft parts during automated fastening processes. The risk intensifies when part frame geometry is complex and fastener locations are close to part features. The lower anvil must be led through an obstructive environment, and there is need for crash protection during side-to-side and lowering motion. An additional requirement is stripping bolt collars using the downward motion of the lower ram, which can require as much as 2500 pounds of pulling force. The retention force on the lower anvil would therefore need to be in excess of 2500 pounds. To accomplish this a CNC controlled electromagnetic interface was developed, capable of pulling with 0-3400 pounds. This electromagnetic safety base releases when impact occurs from the sides or during downward motion (5 sided crash protection), and it retains all riveting and bolting functionality.

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.

Two Automated Electromagnetic Riveting Assembly Cells (AERAC) were manufactured for Textron Aerostructures by Electroimpact, Inc. The AERAC installs the final rivets in the A330/A340 upper wing panel in the floor assembly jig. At Textron for each wing the corresponding floor assembly jigs for each wing are lined up end to end. An operating procedure in which the formboards are removed in bays allows efficient operation of an in the jig riveter such as the AERAC. Specialized machine codes developed for the AERAC allows quick fully programmed stringer to stringer jumps of the stringer side offset tooling. The AERAC is programmed entirely from a CATIA drawing of the part. Of the 5 axes of rivet data available only two are retained for use by the AERAC.