Hand portable 3D mapper applied to pit quantification on aerospace parts

摘要

The quantification of surface defects such as corrosion pitting, scratches and wear on high value aerospace parts offers many challenges. The parts may be highly curved airfoils, narrow slots in rotating parts, or widely scattered points on large structures that are not easily moved. The traditional precision tools for micron level measurements of this type are typically benchtop units in a microscope format that is not viable for mapping small areas on large, hard to handle parts. The large area 3D mappers have more flexibility but are hard pressed to provide the few micron measurement resolution needed while providing too much data on a volumetric area where only small local measures are needed. This paper will discuss the application of a hand portable, structured light system that offers both resolution and flexibility. The challenges of curved surfaces and hard to reach areas will be discussed in the context of the practical restraints imposed by system depth-of-field and good pattern contrast needed for high quality 3D measurements.