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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.

This paper describes ongoing research into orbital drilling using standard industrial robots. The research is a part of an ongoing EU funded aircraft industry project - ADFAST*. Generally it is difficult to use standard industrial robots to automate drilling in the aerospace industry. The stiffness of the standard robotic device is not sufficient to resist the deflections caused by the cutting forces from the drilling process, therefore it is difficult to achieve the tight hole tolerance requirements. Orbital drilling creates lower axial cutting forces compared to conventional drilling and therefore allows the use of low-cost standard industrial robots for drilling holes within the required hole tolerances. This paper presents results from a study where forces, moments and dislocations produced during orbital- and conventional drilling have been measured.

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*.

This paper deals with issues about Orbital drilling implementation and evaluation. The paper summarizes and includes the so far written papers about Orbital drilling. In a previous paper, a conclusion was made, orbital drilling is a suitable method for drilling high quality holes in the specific space application that was studied. The conclusion for further development was then to look more specifically into the process development, i.e. cutting parameters, new cutters, new coatings on cutters etc. Then the investigation and feasibility study started. The project went from early prestudy to fully implemented industrialized solution of the PODU at SAAB Ericsson Space (SES) in Linköping, Sweden. More detailed description on how the project did it is explained in the paper. The early conclusions made after pre- and final acceptance tests of the PODU at SES shows that Orbital drilling is a comprehensive method compared to conventionally drilling methods.