Backprojection Reconstruction of Laser-Drilled Cooling Holes1

Abstract

Automated laser drilling of cooling holes in jet engine parts is an important part of the aircraft engine manufacturing process. Proper hole placement and shape is critical to attaining required cooling function without sacrificing structural integrity. Due to variability in the laser drilling process, each hole must be inspected individually. A video camera coupled with a precision, computer-controlled manipulator such as that used to position the part for the drilling of each hole, offers the potential for an accurate, high speed inspection system.