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A GREAT deal has been said recently about the decentralized production scheme developed by Vickers‐Armstrongs Ltd. and approved by the Air Ministry, so that we are particularly pleased to be able to give an outline of its operation on one of the first types to be so constructed in series. It is common practice to sub‐contract minor assemblies and specialized work, but, in the case of the Spitfire I, many major assemblies such as main planes, all control surfaces, engine mountings and tail units are made out and brought together to be assembled at Woolston, Itchen or Eastleigh.

Describes the ARMA concept, adaptive robotized multifunction assembly cell, as used at CTRI Robotics, a division of Dassault Aviation. The concept evolved in response to the demand for flexibility in automation system design, having recognized the inherent limitations of overspecialized equipment. Defines the mobility and placement corrective systems, the assembly process, information system, programming system, quality system, cell pilot, process control and man/machine interface. Concludes that the ARMA concept was implemented to provide the capabilities necessary automatically to assemble the Rafale fighter but, more importantly, is flexible enough also to assemble other and future aircraft.

Riveting deformation is inevitable because of local relatively large material flows and typical compliant parts assembly, which affect the final product dimensional quality and fatigue durability. However, traditional approaches are concentrated on elastic assembly variation simulation and do not consider the impact of local plastic deformation. This paper aims to present a successive calculation model to study the riveting deformation where local deformation is taken into consideration.

Based on the material constitutive model and friction coefficient obtained by experiments, an accurate three-dimensional finite element model was built primarily using ABAQUS and was verified by experiments. A successive calculation model of predicting riveting deformation was implemented by the Python and Matlab and was solved by the ABAQUS. Finally, three configuration experiments were conducted to evaluate the effectiveness of the model.

The model predicting results, obtained from two simple coupons and a wing panel, showed that it was a good compliant with the experimental results, and the riveting sequences had a significant effect on the distribution and magnitude of deformation.

The proposed model of predicting the deformation from riveting process was available in the early design stages, and some efficient suggestions for controlling deformation could be obtained.

A new predicting model of thin-walled sheet metal parts riveting deformation was presented to help the engineers to predict and control the assembly deformation more exactly.

The purpose of this paper is to investigate the strain concentration factor in a central countersunk hole riveted in rectangular plates under uniaxial tension using finite element and response surface methods.

In this work, ANSYS software was elected to create the finite element model of the present structure, execute the analysis and generate strain concentration factor (,) data. Response surface method was implemented to formulate a second order equation to precisely compute (,) based on the geometric and material parameters of the present problem.

The computations of this formula are accurate and in a great agreement with finite element analysis (FEA) data. This equation was further used for obtaining optimum hole and plate designs.

An optimum design of the countersunk hole and the plate that minimizes the (,) value was achieved and hence validated with FEA findings.

The riveting process is a metal forming process involving complex elastic-plastic deformation, which will induce a compressive residual stress field and cause local distortions in the connecting areas. Regarding to the aircraft panel assemblies with plenty of rivets, the global deformation is inevitable and undesired, leading difficulties to downstream assembly processes. This paper aims to present a new method for the local distortion calculation and the global deformation prediction of sheet panel assemblies during the automated riveting process.

In this paper, a simplified algebraic study is presented to analyze the local distortion of single countersunk rivet joint with the consideration of the barrel-like shape of the driven head and the through-thickness variations along the rivet shank. Then, an equivalent rivet unit is proposed based on the result of the algebraic study and embedded into the global-level model for the prediction of the overall distortions of riveted panels.

The algebraic study is able to reach a more precise contour of the deformed rivet than the traditional assumption of cylindrical deformations and rapidly determine the equivalent coefficients of the riveting unit. The result also shows an industrial acceptable accuracy of the prediction for the global deformations of the double-layered panel assemblies widely used in the aircraft panel structures.

A new local-global method for predicting the deformations of the riveted panel assembly based on the algebraic study of the local distortions is proposed to help the engineers in the early design stages or in the assembly process planning stage.

WHEN a new aeroplane is produced, every effort is made to ensure that it will be free from the “bugs”, to use that expressive word of the aircraft industry, experienced on previous types. This goal is usually attained, but unfortunately the sum total of defects does not decrease, mainly because new and comparatively untried ideas will have been incorporated to improve the new aircraft. Defects arising from these will most probably outweigh those obviated by experience, and so, until finality in design is reached, there will continue to be design defects. Another factor is that the other aircraft with which the comparison is being made will usually have been in service for some time and their teething ailments largely eliminated and thus forgotten.

CONTROLLED EXPANSION has an important implication in the mechanical fastening of high performance structures. The technique provides that a cylindrical fastener expands plastically during installation to a slightly hour glass shaped cross section. Expansion is one to two per cent of the hole diameter at the shear plane, and three to five per cent at the surfaces. The result is a joint with remarkable integrity and attractive in cost saving potential. The advantages of controlled expansion are being incorporated into the fastening of the A300B wing structure after a critically thorough study of the systems described herein, in comparison with all proven and potential alternatives.

THIS presentation on fastening of composite structures includes material characteristics, hole generation parameters and methods, types of fasteners available and automation equipment and approaches.

The purpose of this paper is to present a review about sizing of joints, from the static and fatigue points of view. A discussion about advantages and disadvantages of each joining technology, among the ones mentioned above, will be presented.

Although many other aspects will be discussed, emphasis will be given to the joint fatigue behavior, and fatigue test results will be presented and discussed.

This paper is a subject review, where no new findings are presented. However, the comparison of fatigue test results for mechanically fastened joints and friction stir welding joints will show the advantages of the latter.

With the information presented, the authors expect to provide some guidelines that will help to improve future joint designs.

The review information contained in this paper may be used as reference for aircraft joint design.

This paper aims to study the influences of eccentricity on the fastener load and bearing strength of the eccentric connection in the aircraft structure.

The special experiment is designed for the researches. The fastener loads of the eccentric connection are gained by using the derived formulas and numerical analysis, and the fastener load rules is verified by the experiment. The bearing strength of the eccentric connection is investigated by the experiments under different eccentricities compared with that gained from the experiment.

The study results are summarized as follows. Magnitude of the fastener load in the eccentric connection is greatly affected by distance from the fastener to the centroid of the fastener cluster and that from the fastener to the concentrated load. With the increase of eccentricity of the homolateral concentrated load, the fastener load increases, and difference of the fastener loads becomes larger, forming the short plate effect of the bucket. It means that fastener with the maximum load (the shortest plate of the bucket) leads to decrease of the bearing strength of the eccentric connection (the capacity of the bucket).

The investigation on the influence of eccentricity on the bearing strength of eccentric connection is firstly presented. The vector expression of the fastener load in eccentric connection is firstly derived. And the influencing mechanism of the fastener load on the bearing strengths of the different eccentric connections is demonstrated. The study results can provide guidance for the structure design of the eccentric connection.