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The purpose of this paper is to examine the effect of changing some riveting parameters on the riveting quality of a riveted aircraft structure. In this study, riveting was performed by applying friction under pressure.

During this friction riveting process, a feed of 3 mm/min was applied in the axial direction. Rotation speed values of 2,000, 2,200 and 2,400 rpm were selected. A 3-axis die milling machine was used to achieve the required positioning, pressing force and friction effect. 1.27 mm-thick Al 7075-T6 sheets and 2117-T3 forged rivets were used. The feed rate was applied at 1 mm/min in both tensile shear and cross-tensile tests.

The feasibility of friction riveting in 2117-T3 rivets was examined, it was shown that it could be done, and the most suitable rotation value for this process was determined.

Clamping force is one of the most important parameters for riveting quality. This study will contribute to a better understanding of the friction-forging riveting process along with the effects of riveting parameters. At the same time, it will lead to more research and expand the application of friction forging riveting to more structural connections.

Aircraft structures are mainly connected by riveting joints, whose quality and mechanical performance are directly determined by vertical accuracy of riveting holes. This paper proposed a combined vertical accuracy compensation method for drilling and riveting of aircraft panels with great variable curvatures.

The vertical accuracy compensation method combines online and offline compensation categories in a robot riveting and drilling system. The former category based on laser ranging is aimed to correct the vertical error between actual and theoretical riveting positions, and the latter based on model curvature is used to correct the vertical error caused by the approximate plane fitting in variable-curvature panels.

The vertical accuracy compensation method is applied in an automatic robot drilling and riveting system. The result reveals that the vertical accuracy error of drilling and riveting is within 0.4°, which meets the requirements of the vertical accuracy in aircraft assembly.

The proposed method is suitable for improving the vertical accuracy of drilling and riveting on panels or skins of aerospace products with great variable curvatures without introducing extra measuring sensors.

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.

Determinative locating and riveting distortions are highly coupled at assembly locale. Recent methods only take every tested or assumed locating errors at the mating surface into the process planning for the assemblies in a simple form. However, the growth of part number makes it nearly infeasible to take every locating error at every mating surface into the dimensional precision calculation. This paper aims to provide a solid riveting process planning for the reduction of practical locating-related distortions.

Large-scale metrology firstly measures the determinative coordinates for the locating-deviated key points. Iterative finite element (FE) analyses then calculate the riveting-related key point distortions from every rivet upsetting directions (UDs) and assembly sequence. These key points on the actual assembly contour and relative FE nodes yield two virtual planes. Virtual plane manipulation adds the riveting distortions into the locating-deviated coordinates. Finally, optimal algorithm integrates the iterative FE analyses with virtual plane manipulation.

Case studies validate that the virtual plane manipulation coincides with the test well, and the proposed method has good compensation of practical locating distortion.

The optimized rivet UDs may be set in a chaotic distribution, which may complicate the abundant riveting operations and the assembly appearance. Therefore, the use of automatic riveting systems can overcome the operational complexity, and the industrial design of rivet UD distribution will improve the assembly appearance.

The optimized UDs and assembly sequence are for assembly workers or automatic riveting systems.

The proposed method is the first to reduce the determinative locating distortion by a novel and efficient solid riveting process planning in detail, and the solid riveting process designed is conservative and accurate for practice.

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 design, analyze and optimize a new type of inner-side working head for automatic horizontal dual-machine cooperative drilling and riveting system. The inner-side working head is the key component of automatic drilling and riveting system, and it is a challenge to design an inner-side working head which must be stiffness and stable with a compact structure to realize its functions.

According to the assembly structure features of large aircraft panels and riveting process requirements, a new type of inner-side working head is designed for pressure riveting. The force condition of the inner-side working head during the riveting process is analyzed and the deformation model is established. Design optimization is performed based on genetic algorithm and finite element analysis. The optimized inner-side working head is tested with automatic horizontal dual-machine cooperative drilling and riveting system.

The deformation model provides the precision compensation basis for control system. Application test results show that the automatic drilling and riveting system can realize assembly of large aircraft panel with high efficiency and quality through the inner-side working head.

The inner-side working head has been used in aircraft panel assembly.

The inner-side working head has been used in aircraft panel assembly.

This paper presents the design, analysis and optimization of a new type of inner-side working head which can realize automatic riveting for aircraft panel. The research will promote the automation of aircraft panel assembly.

The purpose of this paper is to present a dual-robot pneumatic riveting system for fuselage panel assembly, including the system design, dynamic analysis and sensitivity analysis. The dual-robot pneumatic riveting system is designed to improve riveting efficiency and quality, thus finally replace the traditional two-man riveting mode where possible.

The dual-robot pneumatic riveting system has been designed by considering vibration reduction for the tools and isolation for robots. Nonlinear multi-body dynamic model including clearance and collision is established for investigating the dynamic performance and analyzing the systemic sensitivities with respect to the key variations. Semi-implicit Runge–Kuta algorithm is used for solving the dynamic equations and shop experiments are implemented to verify the effectiveness of the numerical simulations.

The simulation results show the tools can be held stably enough for riveting operation and the system sensitivity with respect to robot gesture can achieve the expected level. The experiment validates the proposed system with a good performance, and the riveting quality could adequately meet the requirements. The system is capable of installing an aluminum alloy countersunk 5 mm diameter rivet in 5 s.

The dual robot pneumatic riveting system is successfully developed and test. It has been applied in a project of fuselage panel assembly in the aircraft manufacturing industry in China.

To replace the traditional manual rivet installation, this paper presents a dual robot pneumatic riveting system and includes both the system design and dynamic analysis.

Assembly variations, which will propagate along the assembly process, are inevitable and difficult to analyze in Aeronautical Thin‐Walled Structures (ATWS) assembly. The purpose of this paper is to present a new method for analyzing the variation propagation of ATWS with automated riveting.

The paper addresses the variation propagation model and method by first, forming a novel Stage‐State model to represent the process of automated riveting. Second, the effect of positioning error on assembly variation is defined as propagation variation (PV), and propagation matrix of key characteristic points (KCP) is discussed. Third, the effect between the variations in each stage is defined as expansion variation (EV). According to the analysis of mismatch error and the reference transformation, the expansion matrix is formed.

The model can solve the variation propagation problem of ATWS with automated riveting efficiently, which is shown as an example of this paper.

The variation obtained by the model and method presented in this paper is in conformity with the variation measured in experiments.

The propagation variation and expansion variation is proposed for the first time, and variations are studied according to novel propagation matrix and expansion matrix.

The purpose of this study is to investigate how the sloping head fault in solid riveting affects the strength of the joint and to develop an efficient system for the solution of the problem.

For rivet joints, 1.2-mm thick 2024-T3 plates were used. AD 2117 T4 solid rivets with a diameter of 3.2 mm were chosen for the joints. A new riveting mechanism has been created unmatched in the literature for solid rivets. In the riveting process, the bucking bar surface is positioned at a right angle to the riveting process axis. Alternative 5°, 10° and 15° fault angles were obtained. During the riveting process, a total of eight different test samples were produced, four for each of the tension-shear and cross-tension joints, by making 0°, 5°, 10° and 15° angles to the bucking bar. To determine the mechanical properties of the prepared samples, cross-tensile and linear tensile-shear tests were performed on a universal tensile testing machine. Special apparatus has been designed and produced for cross-tensile tests.

As a result of the tensile-shear tests, the decrease in the joint at 15° was 25% compared to the joint at 0°. There is no systematic change in elongation. As a result of the cross-tensile tests, there was a decrease in the cross-tensile force toward the sample with an error of 15°. Compared to the 0° joint, this decrease was approximately 14.5% in the 10° joint, while the decrease in the 15° faulty joint was 25.8%. It has been understood that riveting with an angle of 0° affects the strength very much.

A new riveting mechanism has been created unmatched in the literature for solid rivets. Experimentally, it has been shown that forged rivets can be made very economically and properly. It has been experimentally proven how much the rivet head shape formed in the wrong forged rivet application changes the result.

IN airframes of all‐metal construction an exceedingly important part is played by the riveting; e.g. no fewer than 250,000 rivets arc needed for the construction of a Focke‐Wulf “Condor.” It will be understood therefore why, with the increasing demands being made on the rate of aircraft production, the question of riveting methods receives such special attention. The object is, to save man‐hours, and thus to increase the rate of production.