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Traditionally, in the civil aerospace industry, assembly fixtures are large, bespoke, permanent structures that are costly to both design and manufacture. Additionally, the time to design, manufacture and install a large fixture can be significant with lead times in excess of 24 months. Within Airbus Operations Ltd there is a requirement to reduce non-recurring costs, reduce the time to market and improve the capacity and flexibility of equipment. This means that while the costs and lead times must be reduced, the utilisation of the tooling should be increased. Flexible and reconfigurable fixtures have not yet been deployed within Airbus Operations Ltd due to the assembly sizes and complex component configurations. However, they offer the potential for reducing costs by utilising off the shelf components. Using standard parts and implementing design tools can reduce the design time.

Drilling is one of the most costly and labour-intensive operations in aircraft assembly. Rather than automating with expensive fixtures and precise machinery, our approach is to make use of standard low-cost robot equipment in combination with sensor feedback. The focus is to eliminate the sliding movement of the end-effector during the clamp-up, called the skating effect, and to keep the end-effector orthogonal to the surface, thus avoiding holes that are not perpendicular. To that end, force feedback is used for building up pressure to clamp up an end-effector to the work-piece surface prior to drilling. The system, including the planning of force parameters for each hole to be drilled, was programmed in DELMIA. The drilling was accomplished with the aid of an extension to the ABB Rapid language called ExtRapid, which is an XML-like code that is interpreted by the force feedback controller downstream in the process.

In this paper solution for low-cost automation of aircraft assembly is presented. The concept of this development is closely related to “Lean Automation”, which in this case concerns the use of modern standard equipment such as standard robots, PC-computers and a newly developed spatial sensor system for precision measurements of positions. The robot is used to perform reconfiguration of tooling modules that are possible to be configured/reconfigured in six degrees of freedom. A prototype developed as the result of an EU-project called ADFAST* has been evaluated at Linköping University in Sweden. Technical functionality is reported where the robot manages to configure the flexible tooling modules to a total error bellow 50 μm. This paper presents the results on the portion of the project addressing robot, metrology system and tooling.

This paper presents preliminary result in a flexible fixture solution for airframe assembly comprising a modular steel framework called Box-joint and flexible tooling modules called Hexapods. The solution is comprises a framework that is screwed together instead of welding beams together, which enables re-building the framework when performing change-over in a more extensive reconfiguration. The Hexapods are parallel legged passive fixture stands that can change their configuration to facilitate easy setup in a change-over between handle different assemblies. A solution to configure the Hexapods manually is described. The investment cost can be kept low by using a metrology system to provide for high accuracy in the tool configuration process instead of using precision parts in the fixture system.

This paper presents preliminary result in a flexible fixture solution for airframe assembly comprising a modular steel framework called Box-joint and flexible tooling modules called Hexapods. The solution is comprises a framework that is screwed together instead of welding beams together, which enables re-building the framework when performing change-over in a more extensive reconfiguration. The Hexapods are parallel legged passive fixture stands that can change their configuration to facilitate easy setup in a change-over between handle different assemblies. A solution to configure the Hexapods manually is described. The investment cost can be kept low by using a metrology system to provide for high accuracy in the tool configuration process instead of using precision parts in the fixture system.

Building prototype aircrafts is costly in tooling especially since only one aircraft is being built. Today's most common tooling strategy is to weld together a beam framework. Welded framework solutions have long lead times both in design and manufacturing and once the aircraft is assembled the tool becomes obsolete. Flexible tooling strategy uses non-welded tooling thus it can be changed and re-used for future products. Early version of a new aircraft model is always hampered by frequent changes in its design, which is cumbersome to handle in a welded framework solution. This paper presents a flexible assembly tooling solutions based on Flexapods and BoxJoint. The Flexapods are commercialized reconfigurable tooling units that are manually adjusted injunction with a laser tracker to a final positional accuracy of +/? 0,05 mm absolute accuracy.

Since the early days of aircraft assembly, welded steel structures called Conventional Tooling has been used for positioning and holding parts in place during assembly. This paper presents a new tooling concept called Affordable Reconfigurable Tooling, where a robot is not only used for drilling and riveting but also for reconfiguring the tool itself. The concept consists of modular units that can either be reconfigured between products of the same family of assembly or rebuilt between product families. The research is part of an ongoing EU-founded aircraft industry project - ADFAST*.