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This paper deals with orbital drilling of sandwich constructions for space applications. Sandwich constructions for space applications are typically made up of thin layers of carbon fiber composite skins separated by an aluminum or carbon honeycomb core. Drilling holes in such structures is required for assembly purposes. A common and significant problem occurs when drilling such structures with conventional methods, namely delamination on the exit side of the composite layers. In this study orbital drilling is investigated as a means of eliminating delaminations and other frequently encountered problems with conventional drilling of laminated composite structures. Holes of different sizes were drilled in sandwich panels using orbital drilling. Both automatic (CNC) and semi-automatic (portable) orbital drilling were investigated. Damage in the vicinity of the holes was assessed by means of microscopic evaluation.

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.

The scope and purpose of this paper is to give input and propose solutions to the creation of an efficient and productive geometrical measurement planning process. The case study outline what is important and how to identify and determine the preconditions and input data which is required to start the preparation and planning activities of geometrical measurements. That is why the following three main research and development questions should be answered: Firstly; What is the need and why does an efficient and productive geometrical measurement planning process contribute to decrease cost upstream as well as downstream in terms of reduced lead times in measurement planning process work? Secondly; Why are reduced uncertainties related to geometrical; functionality, specification and verification, important? And how are they linked to each other and how can they be theoretically modeled and defined in terms of uncertainties?