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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.

The Structures and Materials Research Center of the National Aerospace Laboratory of Japan (NAL) conducted a vertical drop test of a fuselage section from a NAMC YS-11 transport airplane in December2001. This test program is a part of research activities in NAL on the structural crashworthiness of transport aircraft. In addition a cooperative research related to this test program was carried out between NAL and Kawasaki Heavy Industries, Ltd.(KHI). The main objective of this program is to develop optimal numerical models for crash simulation of aircraft fuselage and to obtain background data by drop tests of small-scale structural models and a full-scale fuselage section. Prior to the drop test of a full-scale fuselage structure, a trial numerical simulation on the crash behavior of a small-scale sub-floor structure was conducted by NAL using the explicit, nonlinear dynamic analysis code, LS-DYNA3D.

A new style of rivet injector is in production use on a variety of fastening machines used by major aircraft manufacturers. In this injector the opposing sides of the rivet guide blocks are attached to the arms of a parallel gripper. We have implemented the parallel gripper in both vertical axis and horizontal axis riveting applications. It is equally effective in both orientations. We have implemented the parallel gripper rivet injector on headed rivets, threaded bolts, ribbed swage bolts and unheaded (slug) rivets.

As for automobile, the mass production period of Electric Vehicle(EV) has begun by the rapid progress of the battery performance. But for EV-Motorcycle(MC), it is limited for the venture companies' releases. The design and evaluation methodologies are not yet established or standardized so far. This paper provides the practical and the experimental examples. To study the feasibility of EV-MC, we developed the prototypes in the present technical and suppliers' parts environments, and evaluated them by the practical view of the MC usage. The developed EV-MC has the equivalent driving performance of the 250cc internal combustion engine(ICE)-MC and a cruising range of 100km in normal use.

In the closed environments such as manned space station, it is necessary to remove contaminant gas to keep a suitable environment. Removal of gaseous contaminants generated from crew, animals, and plants is important function to keep the environment below the allowable level in the Closed Ecology Experiment Facilities (abbreviated as CEEF). CEEF consist of three modules for habitat, animal and plant, the supporting facilities for each module and a plant cultivation facility. CEEF are scheduled to be constructed from 1994 in Aomori Prefecture, northern part of Japan. For designing Trace Contaminant Control Assembly (TCCA) for CEEF, the following six (6) trace contaminants have been selected as major contaminant gas in CEEF; Ammonia (NH3) Methane (CH4) Ethylene (C2H4) Carbon Monoxide (CO) Nitrogen Dioxide (NO2) Sulfur Dioxide (SO2) Ethylene is well-known as an aggressive contaminant to plant growth and maturity.

The authors developed an air-to-air surveillance system that acquires mutual position and informs the position to the pilot. This system transmits position information obtained by GPS via TDMA (Time Division Multiple Access) datalink. Position information received from other aircraft is shown on a display. If proximity condition exists, voice alert is activated. This system can be used as an support system for collision avoidance. This paper describes the outline of the system and flight test result. Two prototype systems were installed on two helicopters. The third system was installed on a ground vehicle. Flight tests were performed using these three systems.

Aircraft assembly systems which require tooling or machinery to pulse or move between multiple positions within a factory can be positioned with high repeatability without high performance foundations or sweeping out large areas of floorspace. An example shows a system of large left and right-hand frames which are positioned at 3 sequential manufacturing steps and then recirculated to the start of production via a central return aisle. The frames are 41 ton actual weight and are 72′ long, similar to a rail car. The system achieves rectangular motion for the recirculation path. The supporting and moving system incorporates low-cost rail in a floor with minimal preparation and simple to use controls. The system is also easily reconfigured if the manufacturing system needs to be altered to meet rate or flow requirements.

Structures and Materials Research Center of the National Aerospace Laboratory of Japan (NAL) conducted vertical drop tests of fuselage sections of a NAMC YS-11 A-200 transport airplane. This test program is a part of research activities in NAL on the structural crashworthiness of transport aircraft. In addition a cooperative research related to this test program has been carried out by NAL and Kawasaki Heavy Industries, Ltd.(KHI). The main objectives of this program are to develop optimal numerical models for crash simulation of aircraft fuselage and to obtain background data by drop tests of full-scale fuselage sections under a controlled impact condition. Two sections of the fuselage structure with seats and passenger dummies were tested at different drop velocity to a rigid impact surface(concrete). Finite element models of the test articles for simulation of vertical drop tests were developed using a nonlinear dynamic analysis code, LS-DYNA3D.

“ASKA” is a STOL airplane with Upper Surface Blown type (USB) flaps used to perform research on powered lift technology developed by the National Aerospace Laboratory (NAL). ASKA has four high bypass ratio turbofan engines mounted above and forward of the wings, hydraulically actuated flight controls, and the Stability and Control Augmentation System (SCAS). The SCAS is a triple redundant system with three digital computers. In order to develop and evaluate its control laws, flight simulator tests have been conducted for 9 years during the design phase. Four flights have been devoted to evaluate functions of the SCAS and the control laws. The significant features of the control laws are to realize satisfactory flying qualities in the deep backside region at low airspeeds.

Motorcycle engines are operated at an extremely broad range of revolutions, from 1000 min-1 to 10000 min-1 or more. Ideally, the natural frequency of each part should never match the engine excitation frequency at any point over that entire range of revolution speeds, but practically, there are times when resonance cannot be avoided because the range is so broad, and therefore the vibration amplitude at resonance must be kept low. For this reason, it is important to grasp not only the resonance frequency but also the vibration amplitude at that point. This may be achieved by two methods, measurement and analysis. The direct measurement of vibration is generally difficult because the motorcycle muffler system has a complex shape and in addition it gets very high temperature when the engine is operating. For this reason, with the aim of being able to predict muffler vibration at the design stage, we carried out a vibration test and FEM (finite element method) analysis.

The E7000 riveting machine installs NAS1097KE5-5.5 rivets into A320 Section 18 fuselage side panels. For the thinnest stacks where the panel skin is under 2mm (2024) and the stringer is under 2mm (7075), the normal process of riveting will cause deformation of the panel or dimpling. The authors found a solution to this problem by forming the rivet with the upper pressure foot extended, and it has been tested and approved for production.

A waterjet propulsor has come to be used more popularly for high speed watercrafts such as personal watercrafts. The most difficult problem for designing the waterjet system is that a tradeoff is required to properly determine the best parameters for the waterjet pump and subsequently the best overall propulsion system. This paper presents the design method and performance improvement of the waterjet propulsor used for personal watercrafts. The authors have clarified the performance of the individual component in the waterjet propulsor and improved the component efficiency empirically, and established the method to estimate the thrust and power characteristics of the propulsor on board from the component test results and other design parameters, which enables the optimization of the waterjet system.

Boeing has relied upon the 767 ASAT (ASAT1) since 1983 to fasten the chords, stiffeners and rib posts to the web of the four 767 wing spars. The machine was originally commissioned with a Terra five axis CNC control. The Terra company went out of business and the controls were replaced with a custom DOS application in 1990. These are now hard to support so Boeing solicited proposals. Electroimpact proposed to retrofit with a Fanuc 31I CNC, and in addition, to replace all associated sensors, cables and feedback systems. This work is now complete on two of the four machines. Both left front and right front are in production with the new CNC control.

In the modern aircraft manufacturing, the cost reduction, the manufacturing time reduction, and the weight saving of aircraft are strongly demanded. The Refill Friction Spot Joining [1,2](FSJ, in other words FSSW, Friction Stir Spot Welding), which is one of innovative solid-state joining methodologies based on the Friction Stir Welding[3], is a promising technology that can replace rivets and fasteners. This technology is expected to offer cost reduction and weight saving for the aircraft manufacturing. In this study, to make stronger and reliable joints, the shoulder-plunging process of Refill FSJ was employed. The weldability of the Alodine or Chromic Acid Anodize coated materials along with a faying-surface sealant was investigated. The joint properties, such as tensile shear strengths and corrosion resistance, were evaluated.

Drilling of carbon-fiber-reinforced plastic (CFRP) components in aircraft production presents many challenges. Factors including layup material, layup process, layup orientation, hole tolerance, surface finish, delamination limits, and inspection methods result in a wide range of process times. The purpose of the paper is to provide a framework to understanding the drilling process in CFRP and the resulting hole tolerance, surface finish and delamination. The paper will investigate drilled hole diameters from 3/16\mi (5 mm) up to 1\mi (25.4 mm) drilled thru CFRP/CFRP and CFRP/metallic stacks with automated drilling machines using single-sided clamping.

In this study, the technology that can predict fatigue life for motorcycle exhaust systems is developed. To predict the fatigue life, analyzing the engine vibration, modeling the vibration characteristics of exhaust systems and evaluating the fatigue damage of welded joints are considered essential. This paper shows an integrated numerical simulation and evaluation method. Furthermore, it is also shown with the result of a component vibration test of the muffler assembly to validate the technology. The results indicate a good correlation between the numerical simulation and the test.

This paper describes the predicted results of acoustic transmission loss (T.L.) for a motorcycle muffler. First, the T.L. of a prototype muffler with one expansion chamber was obtained by measuring sound levels at the inlet and outlet ports of the muffler by speaker test. T.L. was then calculated by using a three-dimensional Finite-Element Method (FEM) for acoustic fields in the muffler. There was good coincidence between the calculated T.L. and experimentally observed data. Second, T.L. of the prototype muffler while attached to a motorcycle engine was measured. On this step, however, a similarly calculated T.L. using FEM to consider the effect of exhaust gas temperature in the muffler showed differences from the measured one. It was estimated that muffler body vibration sounds may affect the result. A dynamic analysis of the structure was carried out using FEM to obtain the eigen modes of the muffler body.

As part of a Composite Wing Manufacture Program, Electroimpact was asked to design and develop a small portable milling machine for machining CFRP. The machine needed to be light so it could be lifted by two operators, robust to the production environment, and stiff enough to allow it to cut a 15 mm deep 3/8\mi slot through composite material (CFRP), in one pass, with no delamination. The machine also needed to be capable of performing a 30 mm deep finishing cut, in one pass, with 3 μm or better surface finish. Specialist Polycrystalline Diamond (PDC) roughing cutters were developed for the cutting process to reduce cutting loads and vibration while maximizing cutter life. The machine also needed to be capable of cutting along a 2 axis path. Electroimpact successfully introduced the machine in to the production environment in October 2011, within a 12 month development window.

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.

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.