Optimised trajectory calculation for the automated layup of wide lightning protection tapes on double-curved fuselage sections

Abstract

Lighting strike protection is not intrinsically provided on modern composite built aircraft due to the lower electrical conductivity of composite materials. A highly conductive copper foil is manually applied onto the fuselage in multiple overlapping tapes. Known automation processes are not adequate for wide tapes particularly in the case of large double-curved surfaces. One key technology for enabling an automated process is tape trajectory generation with a focus on automation constraints. We are introducing a new tape application mechanism for a single wide tape. Our algorithm generates geometry induced layup trajectories, taking into account geometric conditions. We experimentally demonstrate a wrinkle-free automated application. Based on the first algorithm, a second algorithm addresses the challenging issue of an optimised surface coverage with multiple tapes for a fuselage section. A tape application fitness criterion is defined and implemented. We point out that a computer-based algorithm is advantageous for determining the proper arrangement of multiple tapes. It is thus now possible to create a multiple tape design that can be applied with an automation process. In addition, the optimisation leads to a reduction of consumed and wasted tape material in the fuselage production process.