  Aircraft maintenance, repair and overhaul industry is gradually switching to
3D scanning for dent inspection. High-accuracy devices allow quick and
repeatable measurements, which translate into efficient reporting and more
objective damage evaluations. However, the potential of 3D scanners is far from
being exploited. This is due to the traditional way in which the structural
repair manual deals with dents, that is, considering length, width and depth as
the only relevant measures. Being equivalent to describing a dent similarly to
a box, the current approach discards any information about the actual shape.
This causes high degrees of ambiguity, with very different shapes (and
corresponding fatigue life) being classified as the same, and nullifies the
effort of acquiring such great amount of information from high-accuracy 3D
scanners. In this paper a 7-parameter model is proposed to describe the actual
dent shape, thus enabling the exploitation of the high fidelity data produced
by 3D scanners. The compact set of values can then be compared against
historical data and structural evaluations based on the same model. The
proposed approach has been evaluated in both simulations and point cloud data
generated by 8tree's dentCHECK tool, suggesting increased capability to
evaluate damage, enabling more targeted interventions and, ultimately, saving
costs.
