Abstract: Square symmetric composite laminate structures, and sub-modules thereof, are provided, along with methods of forming the same. The square symmetric laminate structures include two or more sub-laminate modules, each comprising: a first ply set consisting of a first ply layer oriented at a first angle and a second ply layer oriented at a second angle, a first sum of the first and second angles being ninety degrees; and a second ply set consisting of a third ply layer oriented at a third angle and a fourth ply layer oriented at a fourth angle, a second sum of the third and fourth angles being ninety degrees; wherein the second ply layer is positioned adjacent the third ply layer and the second and third ply layers are both positioned intermediate the first and fourth ply layers, thereby defining a double-double helix arrangement of the respective ply layers. Associated methods are also provided.

Abstract: A sub-laminate module is described for use in forming composite laminate structures. The module includes a first ply set containing a first ply layer oriented at a first angle and a second ply layer oriented at a second angle, the second angle being unequal the first angle; a second ply set containing a third ply layer oriented at a third angle and a fourth ply layer oriented at a fourth angle, the fourth angle being unequal the third angle; first and second equal acute angles are defined by differences between an absolute value of the first and second angles and the third and fourth angles, respectively, wherein the second ply layer is positioned adjacent the third ply layer and the second and third ply layers are both positioned intermediate the first and fourth ply layers, so as to define a staggered double-double helix sequence of the respective ply layers. Associated composite laminate structures and methods are also disclosed.

Abstract: A grid and skin assembly for use in a composite laminate structure is described. The assembly includes a metallic grid having a plurality of intersecting ribs oriented in at least two distinct rib directions offset at a grid angle relative to one another and defining respective intersection points; and a composite laminate skin having a plurality of ply layers comprising a plurality of tapes oriented in at least two distinct tape directions offset at a ply angle relative to one another. The grid angle is at least 25 degrees, the intersection points define glueless joints of the metallic grid, and the grid is a non-aluminum-based material. A grid and method of manufacturing the grid and skin assembly is also described. The method includes a water jet cutting procedure and glueless joint formation due to differing thermal expansion characteristics of the grid and skin.

Abstract: Square symmetric composite laminate structures, and sub-modules thereof, are provided, along with methods of forming the same. The square symmetric laminate structures include two or more sub-laminate modules, each comprising: a first ply set consisting of a first ply layer oriented at a first angle and a second ply layer oriented at a second angle, a first sum of the first and second angles being ninety degrees; and a second ply set consisting of a third ply layer oriented at a third angle and a fourth ply layer oriented at a fourth angle, a second sum of the third and fourth angles being ninety degrees; wherein the second ply layer is positioned adjacent the third ply layer and the second and third ply layers are both positioned intermediate the first and fourth ply layers, thereby defining a double-double helix arrangement of the respective ply layers. Associated methods are also provided.

Abstract: A sub-laminate module is described for use in forming composite laminate structures. The module includes a first ply set containing a first ply layer oriented at a first angle and a second ply layer oriented at a second angle, the second angle being unequal the first angle; a second ply set containing a third ply layer oriented at a third angle and a fourth ply layer oriented at a fourth angle, the fourth angle being unequal the third angle; first and second equal acute angles are defined by differences between an absolute value of the first and second angles and the third and fourth angles, respectively, wherein the second ply layer is positioned adjacent the third ply layer and the second and third ply layers are both positioned intermediate the first and fourth ply layers, so as to define a staggered double-double helix sequence of the respective ply layers. Associated composite laminate structures and methods are also disclosed.

Abstract: Systems and methods related to the determination of one or more mechanical characteristics of a structural element are generally described. In some embodiments, a mechanical characteristic (e.g., a crack, a deformation, an inclusion, etc.) can be determined based at least in part upon the determination of a temperature generated, for example, by passing a current through a network of structures within the structural element. For example, in some embodiments, the structural element can comprise a network of electrically conductive nanostructures and, in some cases, a primary structural material that is not substantially electrically conductive. An electrical current can be passed through the network of electrically conductive nanostructures (e.g., by passing current through an electrical circuit comprising the network of electrically conductive nanostructures). This may result in resistive heating (also known as Joule-effect heating) of the nanostructure network.

Abstract: Systems and methods related to the determination of one or more mechanical characteristics of a structural element are generally described. In some embodiments, a mechanical characteristic (e.g., a crack, a deformation, an inclusion, etc.) can be determined based at least in part upon the determination of a temperature generated, for example, by passing a current through a network of structures within the structural element. For example, in some embodiments, the structural element can comprise a network of electrically conductive nanostructures and, in some cases, a primary structural material that is not substantially electrically conductive. An electrical current can be passed through the network of electrically conductive nanostructures (e.g., by passing current through an electrical circuit comprising the network of electrically conductive nanostructures). This may result in resistive heating (also known as Joule-effect heating) of the nanostructure network.

Abstract: Systems and methods related to the determination of one or more mechanical characteristics of a structural element are generally described. In some embodiments, a mechanical characteristic (e.g., a crack, a deformation, an inclusion, etc.) can be determined based at least in part upon the determination of a temperature generated, for example, by passing a current through a network of structures within the structural element. For example, in some embodiments, the structural element can comprise a network of electrically conductive nanostructures and, in some cases, a primary structural material that is not substantially electrically conductive. An electrical current can be passed through the network of electrically conductive nanostructures (e.g., by passing current through an electrical circuit comprising the network of electrically conductive nanostructures). This may result in resistive heating (also known as Joule-effect heating) of the nanostructure network.