Abstract: Methods and apparatus for performing repair operations using an unmanned aerial vehicle. The methods are enabled by equipping the UAV with tools for rapidly repairing a large structure or object (e.g., an aircraft or a wind turbine blade) that is not easily accessible to maintenance personnel. In accordance with various embodiments disclosed below, the unmanned aerial vehicle may be equipped with an easily attachable/removable module that includes an additive repair tool. The additive repair tool is configured to add material to a body of material. For example, the additive repair tool may be configured to apply a sealant or other coating material in liquid form to a damage site on a surface of a structure or object (e.g., by spraying liquid or launching liquid-filled capsules onto the surface). In alternative embodiments, the additive repair tool is configured to adhere a tape to the damage site.

Abstract: A method for inspecting a fastened structure, the fastened structure having at least one structural member defining a bore therein and a mechanical fastener received in the bore, includes applying acoustic energy to the fastened structure, the acoustic energy being applied over a plurality of frequencies, measuring a response of the fastened structure across at least two frequencies of the plurality of frequencies, and comparing the response of the fastened structure at the at least two frequencies of the plurality of frequencies to predefined values for the at least two frequencies of the plurality of frequencies to determine whether an out-of-tolerance condition is present.

Abstract: An example system for in-situ inspection of a composite structure includes a surface-strain imaging apparatus and a controller. The surface-strain imaging apparatus is configured to image an area of an outer surface of the composite structure while a temperature of the composite structure warms to thermal equilibrium with a surrounding environment and a temperature gradient exists within the composite structure. The controller includes a processor and a memory, and is configured to detect, using data received from the surface-strain imaging apparatus, an out-of-plane displacement of the outer surface in the area caused by the temperature gradient. The controller is also configured to determine that the out-of-plane displacement satisfies a threshold condition and, based on determining that the out-of-plane displacement satisfies the threshold condition, flag the area of the outer surface for further inspection.

Abstract: Methods comprise generating an electric field; encompassing fibers within the electric to orient the fibers in a desired orientation relative to each other; and subsequent to the encompassing, fixing the fibers in the desired orientation within a matrix material to at least partially create a composite part.

Abstract: A system for inspecting a structure includes a laser ultrasound device configured to direct laser light onto a surface of the structure that generates ultrasonic waves within the structure and to generate an array of ultrasound data representative of the ultrasonic waves. The system includes a robotic arm configured to move the laser light across the surface. The system includes a multiplex controller configured to trigger generation of the ultrasonic waves within the structure at an inspection location and to receive the array of ultrasound data for the inspection location. The system includes a computer system that includes a motion-control module configured to control movement of the laser light relative to the surface of the structure, a motion-tracking module configured determine when the laser light is at the inspection location, and an inspection module configured to process the array of ultrasound data to inspect the structure at the inspection location.

Abstract: An example system for in-situ inspection of a composite structure includes a surface-strain imaging apparatus and a controller. The surface-strain imaging apparatus is configured to image an area of an outer surface of the composite structure while a temperature of the composite structure warms to thermal equilibrium with a surrounding environment and a temperature gradient exists within the composite structure. The controller includes a processor and a memory, and is configured to detect, using data received from the surface-strain imaging apparatus, an out-of-plane displacement of the outer surface in the area caused by the temperature gradient. The controller is also configured to determine that the out-of-plane displacement satisfies a threshold condition and, based on determining that the out-of-plane displacement satisfies the threshold condition, flag the area of the outer surface for further inspection.

Abstract: Methods and apparatus for performing repair operations using an unmanned aerial vehicle. The methods are enabled by equipping the UAV with tools for rapidly repairing a large structure or object (e.g., an aircraft or a wind turbine blade) that is not easily accessible to maintenance personnel. In accordance with various embodiments disclosed below, the unmanned aerial vehicle may be equipped with an easily attachable/removable module that includes an additive repair tool. The additive repair tool is configured to add material to a body of material. For example, the additive repair tool may be configured to apply a sealant or other coating material in liquid form to a damage site on a surface of a structure or object (e.g., by spraying liquid or launching liquid-filled capsules onto the surface). In alternative embodiments, the additive repair tool is configured to adhere a tape to the damage site.

Abstract: Methods comprise generating an electric field; encompassing fibers within the electric to orient the fibers in a desired orientation relative to each other; and subsequent to the encompassing, fixing the fibers in the desired orientation within a matrix material to at least partially create a composite part.