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The foundation of many production aircraft assembly facilities is a more dynamic and unpredictable quantity than we would sometimes care to admit. Any tooling structures constructed on these floors, no matter how thoroughly analyzed or well understood, are at the mercy of settling and shifting concrete, which can cause very lengthy and costly periodic re-certification and adjustment procedures. It is with this in mind, then, that we explore the design possibilities for one such structure to be built in Belfast, North Ireland for the assembly of the Shorts C-Series aircraft wings. We evaluate the peak floor pressure, weight, gravity deflection, drilling deflection, and thermal deflection of four promising structures and discover that carefully designed pivot points and tension members can offer significant benefits in some areas.

A significant step is achieved on the flight control actuation system toward the more electrical aircraft through the Airbus A380, A400M and the A350 development phase ongoing. The A380/A400M/A350 features a mixed flight control actuation power source distribution, associating electrically powered actuators with conventional FlyByWire hydraulic servocontrols. In the scope of the preparation of the future Airbus Aircraft, this paper presents the perspectives of the use of the EMA technologies for the flight control systems in the more electrical aircraft highlighting the main technical challenges need to treat: jamming susceptibility, ?on board? maintenance reduction, Operational reliability increase, power electronics and power management optimization, and regarding the environmental constraints, the predicted performances; the benefits associated to the optimized utilization of on-board power sources.

Serial link articulated robots applied in aerospace assembly have largely been limited in scope by deficiencies in positional accuracy. The majority of aerospace applications require tolerances of +/−0.25mm or less which have historically been far beyond reach of the conventional off-the-shelf robot. The recent development of the accurate robot technology represents a paradigm shift for the use of articulated robotics in airframe assembly. With the addition of secondary feedback, high-order kinematic model, and a fully integrated conventional CNC control, robotic technology can now compete on a performance level with customized high precision motion platforms. As a result, the articulated arm can be applied to a much broader range of assembly applications that were once limited to custom machines, including one-up assembly, two-sided drilling and fastening, material removal, and automated fiber placement.

Titanium is a difficult material to fabricate into complex configurations. There is several elevated temperature forming processes available to produce titanium components for aerospace applications. The processes to be discussed are Superplastic Forming (SPF), hot forming and creep forming. SPF uses a tool that contains the required configuration and seals around the periphery so inert gas pressure can be used to form the material. Of the processes to be discussed, this is the one that can produce the most complex shapes containing the tightest radii. A variation of the process combines an SPF operation with diffusion bonding (SPF/DB) of two or more pieces of titanium together to produce integrally stiffened structure containing very few fasteners. Another process for shaping titanium is hot forming. In this process, matched metal tools, offset by the thickness of the starting material, are used to form the part contour at elevated temperature.

Automated countersink measurement methods which require contact with the workpiece are susceptible to a loss of accuracy due to cutting debris and lube build-up. This paper demonstrates a non-contact method for countersink diameter measurement on CFRP which eliminates the need for periodic cleaning. Holes are scanned in process using a laser profilometer. Coordinates for points along the countersink edge are processed with a unique filtering algorithm providing a highly repeatable estimate for major and minor diameter.

In an attempt to be more flexible and cost effective, Aerospace Manufacturers have increasingly chosen to adapt a manufacturing style which borrows heavily from the Automotive industry. To facilitate this change in methodologies a system for locating robots has been developed which utilizes cameras for both locating and guidance of a mobile platform for a robot with drilling and fastening end effector.

Electroimpact has recently produced a high-speed fuselage panel fastening machine which utilizes an all-electric, CNC-controlled squeeze process for rivet upset and bolt insertion. The machine is designed to fasten skin panels to stringers, shear ties, and other internal fuselage components. A high riveting rate of 15 rivets per minute was achieved on the first-generation E7000 machine. This rate includes drilling, insertion, and upset of headed fuselage rivets. The rivets are inserted by a roller screw-driven upper actuator, with rivet upset performed by a lower actuator driven by a high-load-capacity ball screw. The rivet upset process can be controlled using either position- or load-based feedback. The E7000 machine incorporates a number of systems to increase panel processing speed, improve final product quality, and minimize operator intervention.

Electroimpact's newest riveting machine features a track-style injector with Bomb Bay Ejection Doors. The Bomb Bay Ejection Doors are a robust way to eject fasteners from track style injector. Track style injectors are commonly used by Electroimpact and others in the industry. Using the Bomb Bay Doors for fastener ejection consists of opening the tracks allowing very solid clearing of an injector when ejecting a fastener translating to a more reliable fastener delivery system. Examples of when fastener ejection is needed are when a fastener is sent backwards, when there are two in the tube, or when a machine operator stops or resets the machine during a fastening cycle. This method allows fasteners to be cleared in nearly every situation when ejecting a fastener is required. Additional feature of Electroimpact's new injection system is integrated anvil tool change.

Traditionally, automated fiber placement (AFP) motion platforms use rack and pinion drive trains coupled through a gearbox to a rotary motor. Extensive use of non-contact linear motors on a new AFP motion platform produces a quiet, low-maintenance system without sacrificing precision. A high-rail gantry arrangement allows dynamic performance improvements to machine acceleration and speed, while lowering power consumption costs and capital expenses. The seventh axis incorporated into the machine arrangement effectively produces an effective “five sides of a cube” work envelope, permitting complex spar and panel fabrication.

Developing the most advanced wing panel assembly line for very high production rates required an innovative and integrated solution, relying on the latest technologies in the industry. Looking back at over five decades of commercial aircraft assembly, a clear and singular vision of a fully integrated solution was defined for the new panel production line. The execution was to be focused on co-developing the automation, tooling, material handling and facilities while limiting the number of parties involved. Using the latest technologies in all these areas also required a development plan, which included pre-qualification at all stages of the system development. Planning this large scale project included goals not only for the final solution but for the development and implementation stages as well. The results: Design/build philosophy reduced project time and the number of teams involved. This allowed for easier communication and extended development time well into the project.

In many existing AFP cells manual inspection of composite plies accounts for a large percentage of production time. Next generation AFP cells can require an even greater inspection burden. The industry is rapidly developing technologies to reduce inspection time and to replace manual inspection with automated solutions. Electroimpact is delivering a solution that integrates multiple technologies to combat inspection challenges. The approach integrates laser projectors, cameras, and laser profilometers in a comprehensive user interface that greatly reduces the burden on inspectors and decreases overall run time. This paper discusses the implementation of each technology and the user interface that ties the data together and presents it to the inspector.

The Boeing Company is striving to improve quality and reduce defects and injuries through the implementation of lightweight “Right Sized” automated drill and fasten equipment. This has lead to the factory adopting Boeing developed and supplier built flex track drill and countersink machines for drilling fuselage circumferential joins, wing panel to spar and wing splice stringers. The natural evolution of this technology is the addition of fastener installation to enable One Up Assembly. The critical component of One Up Assembly is keeping the joint squeezed tightly together to prevent burrs and debris at the interface. Traditionally this is done by two-sided machines providing concentric clamp up around the hole while it is being drilled. It was proposed that for stiff structure, the joint could be held together by beginning adjacent to a tack fastener, and assemble the joint sequentially using the adjacent hole clamp up from the previous hole to keep the joint clamped up.

Over 1,200 large diameter holes must be drilled into the side-of-body join on a Boeing commercial aircraft's fuselage. The material stack-ups are multiple layers of primarily titanium and CFRP. Due to assembly constraints, the holes must be drilled for one-up-assembly (no disassembly for deburr). In order to improve productivity, reduce manual drilling processes and improve first-time hole quality, Boeing set out to automate the drilling process in their Side-of-Body join cell. Implementing an automated solution into existing assembly lines was complicated by the location of the target area, which is over 15 feet (4 meters) above the factory floor. The Side-of-Body Drilling machines (Figure 1) are capable of locating, drilling, measuring and fastening holes with less than 14 seconds devoted to non-drilling operations. Drilling capabilities provided for holes up to ¾″ in diameter through stacks over 4.5″ thick in a titanium/CFRP environment.

The newest generation of automated fastening machines require a feed system that is smaller, more flexible, and faster than any currently available. The feed system must be compact enough to fit on a robot base, yet have a capacity large enough to support unmanned production for hours. A large variety of fasteners must be supported and the entire system must be reloaded or reconfigured in minutes to match the next work piece being assembled by the machine. When requested by the part program, the correct fastener must be released directly and immediately into the feed tube to minimize cycle time. This paper describes a new “plate cartridge” feed system developed to meet these needs.

Very large multi-axis CNC machines offer a special challenge for efficient and accurate machine compensation. Aerospace applications demand tight tolerances, but conventional compensation methods become expensive for large machines. Volumetric compensation offers an approach for reducing costs and improving accuracies. A unique control architecture enabled by volumetric compensation enables the use of a single part program by multiple machines. Combining multiple technologies (a proprietary volumetric compensation solver program, Spatial Analyzer, API's Active Target, a laser tracker and bespoke CNC-Tracker communication software for measurement triggering) significantly reduces machine compensation time. Available analysis tools also enable the engineer to evaluate measurement uncertainties and determine the best locations for additional stations as well as quantify the accuracy benefits such stations would offer.

Electroimpact has developed a new automated squeeze riveting process. This process utilizes an innovative coaxial riveting head design in which the drill spindle and rivet driver share a common servo axis, with a simple toggle mechanism to switch which tool is active. This system has been optimized for the installation of headed solid rivets which can be automatically installed without the need for additional process tools beyond the drill and driver. By optimizing for the requirements of these rivets, Electroimpact has been able to eliminate much of the complexity typically seen on automated fastening equipment, resulting in an unprecedentedly simple and cost-effective design.

One of the largest advancements in the use of the Flextrack technology is the addition of automated fastener installation on the Multifunction Flextrack made by Electroimpact. The new Flextrack installs SSTF (Single Sided Temporary Fasteners) into the holes it drills without removing clamp-up force from the workpiece. This is the first Flextrack to drill and install fasteners and its functionality goes beyond even these functions. The fasteners, SSTF bolts, are increasingly replacing more cumbersome and manual tools for temporary fastening of aerospace components during assembly. They provide doweling, clamp-up, and feature a compact head to facilitate machine installation. The new Multifunction Flextrack carries the bolts on the machine head as opposed to being fed through a feed tube. A Bolt Cartridge System carries up to 80 bolts onboard the Flextrack and the Cartridges can be quick changed for use with several different diameters.

The use of portable automated equipment has increased in recent years with the introduction of flex track, crawling robots, and other innovative machine configurations. Portable automation technologies such as these lower infrastructure costs by minimizing factory floor space requirements and foundation expenses. Portable automation permits a higher density of automated equipment to be used adjacent to aircraft during assembly. This equipment also allows concurrent work in close proximity to automated processes, promotes flexibility for changes in rate, build plan, and floor space requirements throughout the life of an airplane program. This flexibility presents challenges that were not encountered with traditional fixed machine drilling centers. The work zone surrounding portable machines is relatively small, requiring additional setup time to relocate and position machines near the airframe.

Automated Fiber Placement (AFP) machines typically consist of 3 linear and 3 rotary axes of motion in order to manufacture complex shapes. These axes are generally orthogonal and semi-coupled. In these designs, a linear axis move will not affect the rotary axes orientation whereas a rotary axis move will affect the Tool Center Point (TCP) location with respect to the linear axes position. The wide range of motion required to maintain the compaction-axis normality needed for carbon fiber layup tends to prevent all of the rotational axes from passing through the TCP. The location and arrangement of these rotational axes has a great effect on the AFP machine performance and controllability during high speed layup. This paper presents a unique kinematic AFP axes design consisting of replacing the 3 orthogonal rotary axes with 3 tool-center-point-intersecting coupled-axes which decouple the linear axes from the rotary axes.

Wing and fuselage aircraft structures require large precise tools for assembly. These large jigs require periodic re-certification to validate jig accuracy, yet metrology tasks involved may take the tool out of service for a week or more and typically require highly specialized personnel. Increasing the time between re-certifications adds the risk of making out-of-tolerance assemblies. How can we reduce jig re-certification down time without increasing the risk of using out-of-tolerance tooling? An alternative, successfully tested in a prototype tool, is to bring automated metrology tools to bear. Specifically, laser tracker measurements can be automated through a combination of off-the-shelf & custom software, careful line-of-sight planning, and permanent embedded targets. Retro-reflectors are placed at critical points throughout the jig. Inaccessible (out of reach) tool areas are addressed through the use of low cost, permanent, shielded repeatability targets.