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The riveting process with a solid rivet is one of the most applied joining processes in the aeronautic industry. New materials and new design requirements constitute challenges that drive the users to a better understanding of the installation process of riveted joints. Therefore, this study aims with the aid of FEM simulation to understand the phenomena occurring during the installation process and afterwards to predict the mechanical properties of the riveted joint depending on the installation parameters and characteristics of the adherends. The experimental installation process for the validation of the simulation model takes place in a fully automated C-frame riveting machine with all-electric drilling and riveting operations aptitude and continuous collection of process data. This paper deals with the simulation of the installation process. The simulation model consists of a solid rivet with universal head described by the standard EN6081 and aluminum (2024-T351) adherends.

Hybrid (bolted/bonded) joining is becoming one of the innovative joining processes for light weight structures in the transport industry, especially in the aerospace industry where weight reduction and high joining requirements are permanent challenges. Combining the adhesive bonding with the mechanical joining -riveting for instance- can lead to an enhancement of the properties of the joint compared to the wide established riveting, as a result of a synergistic load bearing interaction between the fastener and the adhesive bondline. The influence of the rivet installation process on a hybrid joint regarding the joint stress state, the change of the bondline thickness as well as its effects on the joint performance and load transfer are some of the factors that drive the users to a better understanding of the hybrid joining process.

ECOA is an active software architecture research programme conducted by the French Republic and United Kingdom. It is one product of the recent Defence and Security Co-operation Treaty signed between the two nations. This paper provides an overview of the programme goals and progress as well as an introduction to the technology being developed and comparison to related initiatives. The goal of the ECOA programme is to define an open software architecture that enables collaborative development of mission system software. The ECOA programme is needed to reduce development and lifecycle costs of future military air programmes. For this reason the programme has a specific focus on combat-air mission systems but the underlying technology is general purpose, applying to multiple military and civil domains. At present, the programme has defined a concept, delivered a set of initial technical standards and produced a joint demonstrator to validate the technology developed.

The use of composite materials in aircraft manufactures increases more and more with the need of light weight and efficient airplanes. Combining composite materials with an appropriate joining method is one of the primordial ways of exploiting its light weight potential. Since the widely-established mechanical fastening, which originally, was developed for metallic materials, is not a suitable joining method for composite materials because of its low bearing strength, the adhesively bonding technology might be an appropriate alternative. However, adhesively bonding in the aircraft manufacturing, especially for joining of primary structures is liable to certification requirements, such as testing of every bond up to limit load before the operation begins or non-destructive testing of every bond before the operation begins as proof of the joint characteristics, which cannot be fulfilled with the current state of the art.

A mobile robotic system is presented as a new approach for machining applications of large aircraft components. Huge and heavy workshop machines are commonly used for components with large dimensions. The system presented in this paper consists of a standard serial robot kinematics and a mobile platform as well as a stereo camera system for optical measurements. Investigations of the entire system show that the mechanical design of the mobile platform has no significant influence on the machining accuracy. With mobile machines referencing becomes an important issue. This paper introduces an optical method for determining the position of the mobile platform in relation to the component and shows its accuracy limits. Furthermore, a method for increasing the absolute accuracy of the robots end-effector with help of stereo camera vision is presented.

The high demand of efficient large scale machining operations by concurrently decreasing operating time and costs has led to an increasing usage of industrial robots in contrast to large scaled machining centers. The main disadvantage of industrial robots used for machining processes is their poor absolute accuracy, caused by the serial construction, resilience of gearings and sensitivity for temperature changes. Additionally high process forces that occur during machining of CFRP structures in aerospace industry lead to significant path errors due to low structural stiffness of the robot kinematic. These errors cannot be detected by means of motor encoders. That is why calibration processes and internal control laws have no effect on errors caused by elastic deformation. In this research paper an approach for increasing the absolute accuracy of an industrial milling robot with help of a Laser Tracker system during machining tasks will be presented.

Pilots in fighter aircraft can be subjected to high temperatures during ground operating phases in hot climate conditions, especially if APU mode is not available. A Cooling Generation System (CGS) used with a protective thermal garment for fighter aircraft pilots has been developed that allows cooling of the pilot in the cockpit. The unit is designed to operate under worst case conditions and requires only that the pilot plugs in upon entering the cockpit. A liquid circulates inside the garment that covers the pilot’s torso, arms and head (area under the helmet). The temperatures are defined to guarantee the user’s comfort. The pilot can adjust the power delivered by the CGS, i.e. the temperature of the circulating fluid, up to a maximum cooling capacity of 400 W. The CGS design is based on a small variable speed compressor with a brushless motor, which is the outcome of a dedicated development, and a custom-made evaporator and condenser for maximum efficiency and minimum volume.

Strong market growth, upcoming global competition and the impact of customer-requirements in aerospace industry demand for more productive, flexible and cost-effective machining systems. Industrial robots have already demonstrated their advantages in smart and efficient production in a wide field of applications and industries. However, their use for machining of structural aircraft components is still obstructed by the disadvantage of low absolute accuracy and adverse reaction to process loads. This publication demonstrates and investigates different methods for performance assessment and optimization of robot-based machining systems. For conventional Cartesian CNC machining systems several methods and guidelines for performance assessment and error identification are available. Due to the attributes of a common 6-axis-robot serial kinematics these methods of decoupled and separated analysis fail, especially concerning optimization of the system.

The riveting process in the aerospace industry underlies high requirements to achieve the expected manufacture quality. Process parameters, the choice of materials, and the joint configuration are some influencing factors that can affect the mechanical properties of riveted joints. These high requirements constitute challenges that drive manufacturers to a better understanding of the riveting process. The numerical study of the effect of the installation parameters on the mechanical properties of mechanically fastened joints is one tool to achieve this aim. Usually, three-dimensional finite element simulations of both installation process and mechanical loading of the joint in service must be performed to make detailed numerical predictions of the joint behavior. This paper aims at the reduction of the computational effort.

Alternatives for the environmentally harmful Cr(VI)-based protective coatings for aluminum alloys are highly demanded, especially for aircraft application a. So far, suitable alternative pigments providing inhibiting effects which are comparable to the performance of chromates have not been found. Well known pigments used in corrosion protection coatings are zinc pigments for steel substrates - offering cathodic protection to the substrate and a densification of the coating due to the volume expansion of its corrosion products. Furthermore, it is generally assumed that zinc corrosion products also offer an inhibiting effect. Due to their lower electrochemical potential zinc does not provide cathodic protection to aluminum substrates. To transfer the positive protection effects of zinc to the application of protective coatings on aluminum substrates, zinc pigments have been successfully modified by alloying with magnesium.

Model Based Safety techniques have been developed for a number of years, though the models have not been customised to help address the safety considerations/ actions at each refinement level. The work performed in the MISSA Project looked at defining the content of “safety models” for each of the refinement levels. A modelling approach has been defined that provides support for the initial functional hazard analysis, then for the systems architectural definition level and finally for the systems implementation level. The Aircraft functional model is used to apportion qualitative and quantitative requirements, the systems architectural level is used to perform a preliminary systems safety analysis to demonstrate that a system architecture can satisfy qualitative and quantitative requirements.

Composite materials are increasingly being used in the manufacturing of structural components in aeronautics industry. A consequent light-weight design of CFRP primary structures requires adhesive bonding as the optimum joining technique but is limited due to a lack of adequate quality assurance procedures. The successful implementation of a reliable quality assurance concept for adhesive bonding within manufacturing and in-service environments will provide the basis for increased use of lightweight composite materials for highly integrated aircraft structures thus minimizing rivet-based assembly. The expected weight saving for the fuselage airframe is remarkable and therefore the driver for research and development of key-enabling technologies. The performance of adhesive bonds mainly depends on the physico-chemical properties of adherend surfaces.

In the frame of the development of the European EVA Suit, a complete trade-off was conducted to select the lower torso architecture. This study, performed under an ESA contract, included a formal trade-off dealing with all cost and programmatic impacts together with a technical assessment based on man rated underwater evaluations and analysis. The candidate architectures were: the European baseline including 2 hip and 2 thigh bearings, the Russian like soft ORLAN-DMA, a soft lower torso including 2 thigh bearings and another soft one including 2 calf bearings. The idea was to compare the different design performances without having necessarily developed the 4 pressurized lower torsos and then also to gain experience on predicting methods for such ergonomic/kinematic studies. The trade-off was based on the manned underwater evaluation of ergonomical suit simulators (wet suit concept), supported by the 1-g pressurized evaluation of the Russian ORLAN-DMA and CAD-CAM kinematic analysis.

The Flexible Assembly Cell for Aeronautical Industry (FACAI) is described. The cell was developed in order to take advantage of the benefit of hard automation while retaining the flexibility of the manual assembly system it replaces. A description of both the generic equipment, selected to be non-specific to both the process and the assemblies intended to be built, is provided. In addition, all specific hardware, including end-effectors and fastener distribution systems are described, along with the rationale for their choice. The reasons for the modular design are explained. The means by which the flexibility goal was achieved are outlined. The demonstrated ability of the cell to install a wide range of fasteners (solid rivets, lockbolts, Hilocks) without the need for manual reconfiguration is detailed. The means by which both the quality and safety goals were attained are explained.

This paper synthesizes the shoulder joint development activities performed in the frame of the European EVA Space Suit System (ESSS) programme. The shoulder joint belongs to the anthropomorphic enclosure encompassing the crewmember, protecting him against space environment while ensuring him adequate mobility, dexterity and visibility. A conceptual trade-off selected two candidates likely to fulfil the stringent shoulder joint requirements: an all-soft joint and a hybrid “rolling convolute”. Representative pressurized breadboards were designed, manufactured and tested. The tests addressed both intrinsic performance, via torque/flexion hysteresis curves and ergonomic characteristics via a “man in the loop” evaluation, involving a suit demonstrator. Tests results completed the trade-off, thus enabling the industrial team to formulate recommendations and propose further development studies.

Bleeding in engines is essential to mitigate the unmatched air massflow between low and High Pressure (HP) compressors at low speed settings, thus avoiding unstable operation due to surge and phenomena. However, by emerging the More Electric Aircraft (MEA) the engine is equipped with electrical machines on both high and Low Pressure (LP) spools which enables transfer of power electrically from one spool to another and hence provides the opportunity to operate engine core components closer to their optimum design point at off-design conditions. At lower power setting of the engine, HPC speed can be increased by taking power from LP shaft and feeding it to HP shaft which can lead to the removal of the bleeding system which in turn reduces weight and fuel consumption and help to overcome engine instability issues. Fuel consumption can be decreased by decreasing inconsistent thrust with the aircraft mission for flight and ground idle settings.

The demand for higher production rates in aircraft industry requests more flexible manufacturing solutions. A bottleneck in production is the machining of large components by vast portal machines. Time-consuming referencing processes result in non-satisfying cost-effectiveness of these high-invest-machines. Mobile robot-based solutions are able to operate simultaneously which increases the productivity significantly. However, due to the limited workspace of robots, machining tasks have to be divided and long trajectories are separated in single overlapping segments. Thus high-accuracy referencing strategies are required to achieve desired production tolerances. In this publication different advanced optical reference strategies will be discussed taking the inhomogeneous behavior of a mobile robotic machining system into account.

Avcorp Industries Inc. recognized the need to reduce assembly labor costs in order to stay competitive with global competition. After two years of research and investigation it was determined that a joint project with Dassault Aviation provided the most viable solution. The key elements of the technology developed by Dassault were its high flexibility and rapid payback of capital investment. This paper describes the system and the application. The structure’s design and robotic system design were performed in parallel. A number of design challenges had to be overcome. Many of these issues encountered were common to any automated assembly application. By covering these challenges Avcorp was able to introduce automated assembly at a level that had typically been previously attained exclusively by much larger enterprises. The robotic system consists of two anthropomorphic robots, which work both individually and in tandem.

Due to their unique and favorable properties as well as high strength to weight ratio, composite materials are finding increasing applications in automotive, aircraft and other vehicle manufacturing industries. High demand, production rates and increasing part complexity, together with design variations require fast, flexible and fully automated assembly techniques. In automotive and aircraft manufacturing, widely used bonding and sealing processes are automated using industrial robots due to their speed, flexibility and large working volume. However, there are limitations in achieving complete automation of these processes due to the inherent inaccuracies of the industrial robots, workpiece positioning and process tolerances. Currently, the robot programs are generated in CAD/CAM environment and are adjusted manually according to the actual workpiece.

A lot of studies have been carried out over the last decades on SLD ice accretion challenges. Many of them referred to SLD physics modelling such as break-up, splashing, bouncing, etc… and relied on numerous physics experiments. Different models have been developed in Europe and North-America and have been implemented in several numerical tools, widely in 2D but more and more in 3D. As these tools are intended to be used increasingly among the community, deficiencies have to be deeper investigated. This paper provides some highlights on specific needs linked to SLD impingement and ice accretion, especially for 3D high fidelity computations. Regarding the results, deficiencies on the numerical side and on experimental needs will be highlighted in order to feed brainstorming for ongoing SLD projects such as in European Union H2020 ICE-GENESIS.