Laminated composite shell structure having improved thermoplastic properties and method for its fabrication

A method for fabricating a laminated composite shell structure having improved thermoelastic properties, comprising the steps of:

• generating a three-dimensional strip pattern that conforms to an axisymmetric doubly-curved surface and can be rotated any angle about the vertex of the curved surface relative to an identical fixed strip pattern with centerlines of the strips in the rotated pattern intercepting centerlines of the strips in the fixed pattern at the same angle and at the angle of rotation;
• generating a planar strip pattern from the the three-dimensional strip pattern;
• cutting multiple layers of composite strips using the planar strip pattern;
• laying the composite strips in place on a three-dimensional mold to form multiple layers of overlapping composite strips, the fibers in the multiple layers being arranged at different relative angular orientations;
• and
• curing the composite strips;
• wherein the composite strips are shaped to maintain the fibers at a constant relative angular orientation throughout the shell structure, thus providing a shell structure having quasi-isotropic thermal expansion and contraction characteristics.

A method for developing a line in a curved surface onto a planar surface for fabricating a laminated composite shell structure having improved thermoelastic properties, comprising the steps of:

• generating successive line segments in a developed line corresponding to successive line segments in an original line in the curved surface;
• maintaining the cumulative length of the developed line equal to the cumulative length of the original line;
• and
• ensuring that the angle between each segment of the original line and a local segment of a meridian curve drawn at a constant distance from the planar surface is equal to the angle between the corresponding segment of the developed line and a line in the planar surface drawn parallel to the local segment of the meridian curve;
• wherein the line in the planar surface is used for generating a planar strip pattern from a three-dimensional strip pattern that conforms to an axisymmetric doubly-curved surface and can be rotated any angle about the vertex of the curved surface relative to an identical fixed strip pattern, with centerlines of the strips in the rotated pattern intercepting centerlines of the strips in the fixed pattern at the same angle and at the angle of rotation.