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Several new technologies are now emerging to improve adhesive supply and formulation along with surface treatments that have the potential to offer significant improvements to both surface energy and cleanliness [3]. Additionally, the miniaturisation of laboratory techniques into portable equipment offers potential for online surface energy and chemical analysis measurement for use as quality control measures in a production environment. An overview of newly available technology is given here with several devices studied in further detail. Technologies assessed further in this paper are; portable surface contact angle measurement, ambient pressure plasma cleaning, portable FTIR measurement and adhesive mixing equipment. A number of potential applications are outlined for each device based on the operational technique. The practical aspects of implementation and the perceived technology readiness levels for operation, implementation and results are also given.

There is a growing demand for composites to be utilised in the production of large-scale components within the aerospace industry. In particular the demand to increase production rates indicates that traditional manual methods are no longer sufficient, and automated solutions must be sought. This typically leads to automated forming processes where there are a limited number of effective options. The need for forming typically arises from the inability of layup methods to produce complex geometries of structural components. This paper reviews the current state of the art in automated forming processes, their limitations and variables that affect performance in the production of large scale components. In particular the paper will focus on the application of force and heat within secondary forming processes. It will then review the effects of these variables against the structure of the required composite component and identify viability of the technology.

Currently the wing box rib assembly process requires the manual location and temporary fixing of components within product specific jig or fixtures for drilling. After drilling and reaming, parts are separated, cleaned, deburred prior to adding sealant, reclaiming and final bolting, but this may significantly increase cost, manufacturing lead-time, reduces flexibility and cannot usually be economically modified for use on other aircraft types. Due to potential increase in demand for the next generation single isle aircraft, existing tooling solutions have to be improved and new technologies have to be developed. This paper describes the development and testing of flexible tooling to provide clamping and support for drilling wing box ribs to mating rib posts within a restricted environment. Results are presented along with a discussion of the problems that may be encountered during clamping trials.

Studies of diesel system deposits continue to be the subject of interest and publications worldwide. The introduction of high pressure common rail systems resulting in high fuel temperatures in the system with the concomitant use of fuels of varying solubilizing ability (e.g. ULSD and FAME blends) have seen deposits formed at the tip of the injector and on various internal injector components. Though deposit control additives (DCAs) have been successfully deployed to mitigate the deposit formation, work is still required to understand the nature and composition of these deposits. The study of both tip and internal diesel injector deposits (IDID) has seen the development of a number of bench techniques in an attempt to mimic field injector deposits in the laboratory. One of the most used of these is the Jet Fuel Thermal Oxidation Tester or JFTOT (ASTM D3241).

Current assembly systems that deal with large, complex structures present a number of challenges with regard to improving operational performance. Specifically, aerospace assembly systems comprise a vast array of interrelated elements interacting in a myriad of ways, resulting in a deeply complex process that requires a multi-disciplined team of engineers. The current approach to ramp-up production rate involves building additional main assembly fixtures which require large investment and lead times up to 24 months. Within Airbus Operations Ltd there is a requirement to improve the capacity and flexibility of assembly systems, thereby reducing non-recurring costs and time-to-market. Recent trends to improve manufacturing agility advocate Reconfigurable Assembly Systems (RAS) as a viable solution. Yet, adding reconfigurability to assembly systems further increases both the operational and design complexity.

The replacement for the current single-aisle aircraft will need to be manufactured at a rate significantly higher that of current production. One way that production rate can be increased is by reducing the processing time for assembly operations. This paper presents research that was applied to the build philosophy of the leading edge of a laminar flow European wing demonstrator. The paper describes the implementation of determinate assembly for the rib to bracket assembly interface. By optimising the diametric and the positional tolerances of the holes on the two bracket types and ribs, determinate assembly was successfully implemented. The bracket to rib interface is now secured with no tooling or post processes other than inserting and tightening the fastener. This will reduce the tooling costs and eliminates the need for local drilling, de-burring and re-assembly of the bracket to rib interface, reducing the cycle time of the operation.

The assembly and manufacture of aerospace structures, in particular legacy products, relies in many cases on the skill, or rather the craftsmanship, of a human operator. Compounded by low volume rates, the implementation of a fully automated production facility may not be cost effective. A more efficient solution may be a mixture of both manual and automated operations but herein lies an issue of human error when stepping through the build from a manual operation to an automated one. Hence the requirement for an advanced automated assembly system to contain functionality for inline structural quality checking. Machine vision, used most extensively in manufacturing, is an obvious choice, but existing solutions tend to be application specific with a closed software development architecture.

Aerospace assembly systems comprise a vast array of interrelated elements interacting in a myriad of ways. Consequently, aerospace assembly system design is a deeply complex process that requires a multi-disciplined team of engineers. Recent trends to improve manufacturing agility suggest reconfigurability as a solution to the increasing demand for improved flexibility, time-to-market and overall reduction in non-recurring costs. Yet, adding reconfigurability to assembly systems further increases operational complexity and design complexity. Despite the increase in complexity for reconfigurable assembly, few formal methodologies or frameworks exist specifically to support the design of Reconfigurable Assembly Systems (RAS). This paper presents a novel reconfigurable assembly system design framework (RASDF) that can be applied to wing structure assembly as well as many other RAS design problems.

This paper describes work being conducted by OC Robotics and Airbus to develop snake-arm robots to conduct assembly tasks within wing boxes - an area currently inaccessible for automation. The composite, single skin construction of aircraft structures presents new assembly challenges. Currently during box close-out it is necessary for aircraft fitters to climb into the wing box through small access panels and use manual or power tools to perform a variety of tasks. In future wing designs it may be that certain parts of the wing do not provide adequate access for manual assembly methods. It is also known that these manual interventions introduce health and safety concerns with their associated costs. Snake-arm robots provide a means to replace manual procedures by delivering the required tools to all areas of the wing box. Such a development has broader implications for aircraft design and assembly.

The Airbus A400m has carbon fibre wing panels on both the upper and lower surfaces. When manufactured, these panels come supplied with various lugs on the periphery of the panel. Some are used for lifting the panel, some are used for indexing the panel; however, all lugs must be removed at some time during wing build. Lug thickness varies from 4mm to 14mm; in addition, many lugs must be cut to a 2D profile rather than just straight. The main challenge of the project was to deliver a tool that was small, portable and compact, but that could also accurately slot thick carbon fibre panels, without de-lamination, leaving a good surface finish. The solution was an air powered routing hand tool that was mechanically guided along a 2D path using a cam profile. Special diamond grit cutters were used to cut the initial slot and reduce the machining forces to a bare minimum, with the finishing cut done using a PCD router bit to obtain a good surface finish.

Variability in composite manufacture and the limitations in positional accuracy of common industrial robots have hampered automation of assembly tasks within aircraft manufacturing. One way to handle geometry variations and robot compliancy is to use force control. Force control technology utilizes a sensor mounted on the robot to feedback force data to the controller system so instead of being position driven, i.e. programmed to achieve a certain position with the tool, the robot can be programmed to achieve a certain force. This paper presents an experimental case where a compliant rib is aligned to multiple surfaces using force feedback and an industrial robot system from ABB. Two types of ribs where used, one full size carbon fiber rib, and one smaller metal replica for evaluation purposes. The alignment sequence consisted of several iterative steps and a search procedure was implemented within the robot control system.

This paper will present the latest development of a configurable and modular steel construction system for use in frameworks of flexible fixtures of the kind called Affordable Reconfigurable Fixtures (ART). Instead of a dedicated aircraft fixture, which is very time consuming and expensive, the ART fixtures enable affordable construction from a standard component kit, by solving the main drawbacks of traditional tooling. In early 2009 Airbus UK built the first steel modular fixture for the aerospace industry. The project was a partnership with DELFOi and Linköping University in a project called ReFlex, Reconfigurable Flexible Tooling. A paper was presented in the last year SAE conference which explained about the project in overall. The construction system called BoxJoint has recently been tested in some manufacturing areas at Airbus UK and also been applied in the production at Saab Aerospace Linköping Sweden.

On Airbus aircraft, the undercarriage reinforcing is attached through the lower wing skin using bolts up to 1-inch in diameter through as much as a 4-inch stack up. This operation typically takes place in the wing box assembly jigs. Manual hole drilling for these bolts has traditionally required massive drill templates and large positive feed drill motors. In spite of these large tools, the holes must be drilled in multiple steps to reduce the thrust loads, which adds process time. For the new A380, Airbus UK wanted to explore a more efficient method of drilling these large diameter holes. Introducing automated drilling equipment, which is capable of drilling these holes and still allows for the required manual access within the wing box assembly jig, was a significant challenge. To remain cost effective, the equipment must be flexible and mobile, a llowing it to be used on multiple assemblies.

This paper describes and demonstrates the use of an assembly centric design algorithm as an aid to achieving minimal hard tooling assembly concepts. The algorithm consists of a number of logically ordered design methodologies and also aids the identification of other enabling technologies. Included in the methodologies is an innovative systems analysis tool that enables the comparison of alternative assembly concepts, and the prediction and control of the total assembly error, at the outline stage of the design.

The paper describes a way of generating a cost model, which is aimed to compare different drilling processes. The development of this tool is a part of an ongoing European Union funded aircraft industry project called ADFAST (Automation for Drilling, Fastening, Assembly, Systems Integration, and Tooling). This part of the project involves 4 industrial partners, (Alenia, Airbus Espana SL, Airbus UK and Saab AB), 1 equipment developer (Novator AB) and 1 academic institute (Linkoping University). The model has been created to enable the benefits of an advanced system such as orbital drilling to be quantified. The model is able to generate a cycle time and a cost for the whole drilling process involving equipment, consumables and assembly of varied aircraft structures. The challenge of the task was to develop the ability of modeling a process with a sequence of drilling operations that the model user, in an intuitive way, can select and modify.

This paper presents novel development of a reconfigurable assembly cell which assembles multiple aerostructure products. Most aerostructure assembly systems are designed to produce one variant only. For multiple variants, each assembly typically has a dedicated assembly cell, despite most assemblies requiring a process of drilling and fastening to similar tolerances. Assembly systems that produce more than one variant do exist but have long changeover or involve extensive retrofitting. Quick assembly of multiple products using one assembly system offers significant cost savings from reductions in capital expenditure and lead time. Recent trends advocate Reconfigurable Assembly Systems (RAS) as a solution; designed to have exactly the functionality necessary to produce a group of similar components. A state-of-the-art review finds significant benefits in deploying RAS for a group of aerostructures variants.

Aircraft manufacturers desire to increase production to keep up with anticipated demand. To achieve this, the aerospace industry requires a significant increase in the manufacturing and assembly performance to reach required output levels. This work therefore introduces the Variation Aware Assembly (VAA) concept and identifies its suitability for implementation into aircraft wing assembly processes. The VAA system concept focuses on achieving assemblies towards the nominal dimensions, as opposed to traditional tooling methods that aim to achieve assemblies anywhere within the tolerance band. It enables control of the variation found in Key Characteristics (KC) that will allow for an increase in the assembly quality and product performance. The concept consists of utilizing metrology data from sources both before and during the assembly process, to precisely position parts using motion controllers.

The rising demand for civil aircraft leads to the development of flexible and adaptive production systems in aviation industry. Due to economic efficiency, operational accuracy and high performance these manufacturing and assembly systems must be technologically robust and standardized. The current aircraft assembly and its jigs are characterized by a high complexity with poor changeability and low adaptability. In this context, the use of industrial robots and standardized jigs promise highly flexible and accurate complex assembly operations. This paper deals with the flexible and adaptable aircraft assembly based on industrial robots with special end-effectors for shaping operations. By the development and use of lightweight gripper system made of carbon fiber reinforced plastics the required scaling, robustness and stiffness of the whole assembly system can be realized.

The aerospace manufacturing sector is continuously seeking automation due to increased demand for the next generation single-isle aircraft. In order to reduce weight and fuel consumption aircraft manufacturers have increasingly started to use more composites as part of the structure. The manufacture and assembly of composites poses different constraints and challenges compared to the more traditional aircraft build consisting of metal components. In order to overcome these problems and to achieve the desired production rate existing manufacturing technologies have to be improved. New technologies and build concepts have to be developed in order to achieve the rate and ramp up of production and cost saving. This paper investigates how to achieve the rib hole key characteristic (KC) in a composite wing box assembly process. When the rib hole KC is out of tolerances, possibly, the KC can be achieved by imposing it by means of adjustable tooling and fixturing elements.

Airbus commercial wings are assembled manually in dedicated steel structures. The lead time to design, manufacture and commission these fixtures is often in excess of 24 months. Due to the nature of these fixtures, manufacturing is slow in responding to changes in demand. There is underused capacity in some areas and insufficient ramp-up speed where increased production rate is needed. Reconfigurable Manufacturing Systems and Reconfigurable Assembly Systems (RAS) provide an approach to system design that provides appropriate capacity when needed. The aim of the paper is to review RAS technologies that are suitable for cost-effective wing structure assembly and what knowledge gaps exist for a RAS to be achieved. The paper examines successful cases of RAS and reviews relevant system design approaches. Cost savings are acknowledged and tabularised where demonstrated in research. The research gaps to realising a RAS for wing assembly are identified and different approaches are considered.