Dynamic Structured Light based 3-D Measurement for Aircraft Surfaces

The profile of aircraft surfaces is a critical factor in the performance, efficiency and load capacity of aircraft. Curvature, attack angles, leading and trailing edges of wings determine the lift and drag of the plane during take-off, cruising andlanding. Changes in aircraft surface profile occur during the life of an aircraft due to service or impact loads. Quantitative measurement of smoothness, contour and profile of aircraft surfaces are needed in order to monitor conditions that affect theperformance of planes.We propose a novel non-contact, optical imaging method based on dynamic structured light to obtain an accurate 3-D map of the surface of aircraft parts. The surface elevation at any location can then be automatically and quickly determined frommeasurements of the light and dark changes at that point, without considering any other points on the surface at resolutions up to 0.01 inch over an 8 ft2 area. This automated non-contact system for measuring aircraft surface profile will characterize thecondition of aircraft before and after maintenance operations. The system can be used to locate and quantify dents, dings, loose rivets or screws as well as possible failures of interior components, detected by subtle changes in the surface profile. The DSL 3-D surface measurement technology can considerably benefit both the military and commercial sector. Shrinking defense budgets are calling for improved utilization of existing resources and reducing maintenance and overhaul time, whilemaintaining or increasing level of performance. The maintenance and repair of aging aircraft is one of the critical issues addressed under the new restructuring of defense programs. The proposed technology will greatly help the defense sector in meetingsome of these objectives, by improving the state-of-the-art in the inspection of aircraft airframe structures by characterizing the condition of aircraft wing surfaces before and after maintenance operations.