Composite layup monitoring using structured light

The making of composite parts involves laying down multiple layers of tape in an organized manner. Misplaced ends, wrinkles or other factors can cause the part being built to have weaknesses or other imperfections. However, the actual edges of the tape do not stand out well with each layer reacting differently to lighting. The fiber nature of the tape will make the surface appear bright in some orientations and very dark in other. To complicate the problem, each layer of tape needs to be laid down at different angles, so can be dark, light or in-between, and at positions to fairly tight tolerances. This paper presents a study of several methods for determining the tape position and flaws, as well as details of a structured light method for determining the tape position. Considerations of tolerances, experimental results and how such a system might be implemented will be presented.