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In today's aircraft assembly process several new features make drilling operations very challenging according to production requirements. Parts are made of thin or thick multi-material stacks with a large scope to cover and complex assembly sequences. In addition, the current ramp-up in aircraft programs involves to improve productivity while keeping process quality and reliability. In this context robotic solution meets perfectly all these requirements as it is flexible, reconfigurable, fast and agile. Among the possible end-effectors, the Barrel Multi-Function End Effector (BMFEE) appears to be the most flexible solution to allow many different process configurations. The latest developments have been focused on the drilling equipment of this BMFEE. In fact the drilling process efficiency can be constantly improved especially in terms of reliability, quality and productivity. Therefore vibration-assisted drilling system has been integrated into the BMFEE drilling module.

Aircraft design has mainly changed in the past years, introducing new materials such as CFRP at a large scale. Even if this great change brought many advantages: weight, sustainability, reliability… it upset the way to produce basic parts and to assembly. A special difficulty lies in drilling multiple stacks made of different materials, i.e. metal (aluminum, titanium, stainless steel) + CFPR. Indeed, as the process has to drill through those stacks during a unique operation, cutting conditions and tool technologies are a compromise. As a consequence, tool life cycle, productivity and above all, hole quality are no longer optimum. Some materials, such as titanium requires low cutting speed and high feed rate whereas CFRP requires opposite trends. Moreover, heat generated by cutting metal (especially titanium) can damage CFRP when overheated metallic chips pass through.

The Vibration Assisted Drilling (VAD) process has been implemented in Automated Drilling Equipment (ADE) on an industrial scale since 2011. Today more than 11000 ADEs are currently used on aircraft assembly lines. As well as drawing up a short report on the use of this new process, the authors make an assessment on new challenges that VAD has to face up. Indeed production rates are increasing and ADE manufacturers improve their technologies, one of the most recent and major development concerning the electrical motorization of the machines. These evolutions are as many opportunities for the VAD provided you have a clever understanding as well as an expert knowledge of the process. Thus the authors propose a new dynamic model of the whole VAD system which integrates the behavior of the part, cutting tool/material pair and the machine. The confrontation of model results and experimental validation tests demonstrates the relevance of the works.