A load testing apparatus can include a plurality of vertical load structures arranged on a flight control surface to provide torque on the control surface and reacted by a control rod of the flight control surface. The load testing apparatus can also include a plurality of fore/aft load structures arranged to provide tensile and/or compressive force in a direction intersecting a hinge line of the flight control surface. Each of the plurality of fore/aft load structure can include a first rubber pad having a surface extending in a first plane that is arranged to contact a lower surface of the flight control surface. Each of the plurality of fore/aft load structures can also include a first rubber pad having a surface extending in a second plane that is arranged to contact an upper surface of the flight control surface, wherein the first plane and the second plane are non-parallel planes.

A load testing apparatus can include a plurality of vertical load structures arranged on a flight control surface to provide torque on the control surface and reacted by a control rod of the flight control surface. The load testing apparatus can also include a plurality of fore/aft load structures arranged to provide tensile and/or compressive force in a direction intersecting a hinge line of the flight control surface. Each of the plurality of fore/aft load structure can include a first rubber pad having a surface extending in a first plane that is arranged to contact a lower surface of the flight control surface. Each of the plurality of fore/aft load structures can also include a first rubber pad having a surface extending in a second plane that is arranged to contact an upper surface of the flight control surface, wherein the first plane and the second plane are non-parallel planes.

A bending apparatus for a sample is disclosed. The bending apparatus includes a translation mechanism that translates a vertical displacement/force into a horizontal displacement/force for bending. Components of the bending apparatus are fabricated from a strong, radiolucent material. In these ways, the bending apparatus is compatible with micro-CT imaging, and as such, may be used to bend a sample during imaging. In a particular application, the bending apparatus may be used to measure biomechanical properties of a bone, such as bone strength, bone material properties, fracture toughness, and fracture propagation.

A bending apparatus for a sample is disclosed. The bending apparatus includes a translation mechanism that translates a vertical displacement/force into a horizontal displacement/force for bending. Components of the bending apparatus are fabricated from a strong, radiolucent material. In these ways, the bending apparatus is compatible with micro-CT imaging, and as such, may be used to bend a sample during imaging. In a particular application, the bending apparatus may be used to measure biomechanical properties of a bone, such as bone strength, bone material properties, fracture toughness, and fracture propagation.

A dual indentation test method according to an aspect of the present disclosure may include a first indentation step of indenting a surface of a material using a flat first indenter and a second indentations step of indenting the surface of the material indented by the first indenter using a second indenter.

A dual indentation test method according to an aspect of the present disclosure may include a first indentation step of indenting a surface of a material using a flat first indenter and a second indentations step of indenting the surface of the material indented by the first indenter using a second indenter.

A method of performing an automated non-destructive examination of a composite structure includes identifying surface damage on the composite structure, coupling an automated tap tester device to a surface of the composite structure at a location of the surface damage, and performing, with the automated tap tester device, a plurality of tapping impacts on the surface within a testing area that encapsulates the surface damage. The method also includes receiving a plurality of acoustic signals associated with the plurality of tapping impacts, modeling sub-surface damage associated with the surface damage based on an analysis of the plurality of acoustic signals.

A method of performing an automated non-destructive examination of a composite structure includes identifying surface damage on the composite structure, coupling an automated tap tester device to a surface of the composite structure at a location of the surface damage, and performing, with the automated tap tester device, a plurality of tapping impacts on the surface within a testing area that encapsulates the surface damage. The method also includes receiving a plurality of acoustic signals associated with the plurality of tapping impacts, modeling sub-surface damage associated with the surface damage based on an analysis of the plurality of acoustic signals.

A method is provided for increasing accuracy in measuring complex Young's modulus and complex shear modulus of a material using a processing system. The material is tested to obtain an experimental frequency response transfer function of normal displacement to input force. A model panel is developed in the processing system as a modeled frequency response transfer function. The modeled transfer function is used at a range of fixed frequencies to calculate displacements of the model panel divided by the input force while varying material parameters. The modeled frequency response transfer function is compared with the experimental frequency response transfer function to compute error function values. These values indicate the most accurate material property values as those minimizing the computed error function values.

A method is provided for increasing accuracy in measuring complex Young's modulus and complex shear modulus of a material using a processing system. The material is tested to obtain an experimental frequency response transfer function of normal displacement to input force. A model panel is developed in the processing system as a modeled frequency response transfer function. The modeled transfer function is used at a range of fixed frequencies to calculate displacements of the model panel divided by the input force while varying material parameters. The modeled frequency response transfer function is compared with the experimental frequency response transfer function to compute error function values. These values indicate the most accurate material property values as those minimizing the computed error function values.