Composite laminate thickness compensation

摘要

A method is provided for the non-contact measurement of variations in thickness of composite materials and structures prepared from composite parts. Metrologic methods are employed to provide a 3D image of the structure or part. Variations that are greater than an acceptable amount can be corrected by adding a compensation layer to the surface of the structure or part.

主权项

1. A method for identifying and correcting for variations in thickness in a skin or outer panel designed to be attached to a structural member of a structure, defining a composite article, the method comprising the steps of:
(a) applying composite layers to a mold surface of a forming tool and while on the mold surface, heating the composite layers to cure the composite layers, thereby providing the composite article configured for attachment to the structural member of the structure, the composite article having an inner mold-line surface that when installed faces the structure, and an outer-mold-line surface opposite the inner mold-line surface, the outer mold-line surface having a surface shape which approximates the mold surface, and which defines an outermost surface of the skin or outer panel and which is on a side opposite from the structural member; (b) measuring a profile of portions of the inner mold-line surface of the composite article, and a profile of portions of the mold surface of the forming tool using a coherent laser radar to generate a calculated thickness data set for the composite article, the measured profile of the portions of the mold surface approximating corresponding portions of the profile of the outer mold-line surface of the composite article; (c) analyzing the calculated thickness data set for the composite article and determining if the thickness of any areas of the composite article are not within a predetermined range to thereby identify one or more excursions of the calculated thickness in the any areas when existing, an excursion of calculated thickness being defined as a thickness variation of a portion of the composite article between a calculated thickness of the portion of the composite article and a nominal thickness that is greater than an acceptable amount; (d) correcting for an excursion of the calculated thickness in areas on the outer mold line of the composite article that are outside of the predetermined range by:
(i) providing compensation material that has a thickness substantially the same as the respective excursion, and(ii) applying the compensation material on an outermost surface of the outer mold line and to the respective area of the composite article having the respective excursion.