Abstract: Collapsible structures are disclosed. In one embodiment, the collapsible structure includes a plurality of hinges and a plurality of panels. The plurality of panels are swingably connected by the plurality of hinges so as to form at least one arch when the collapsible structure is in an erected state and so as to become at least one stack of the plurality of panels in a collapsed state. The panels allow for the collapsible structure to maintain its structural integrity when erected but to have a compact and transportable configuration when collapsed.

Abstract: Collapsible structures are disclosed. In one embodiment, the collapsible structure includes a plurality of hinges and a plurality of panels. The plurality of panels are swingably connected by the plurality of hinges so as to form at least one arch when the collapsible structure is in an erected state and so as to become at least one stack of the plurality of panels in a collapsed state. The panels allow for the collapsible structure to maintain its structural integrity when erected but to have a compact and transportable configuration when collapsed.

Abstract: Collapsible structures are disclosed. In one embodiment, the collapsible structure includes a plurality of hinges and a plurality of panels. The plurality of panels are swingably connected by the plurality of hinges so as to form at least one arch when the collapsible structure is in an erected state and so as to become at least one stack of the plurality of panels in a collapsed state. The panels allow for the collapsible structure to maintain its structural integrity when erected but to have a compact and transportable configuration when collapsed.

Abstract: Collapsible structures are disclosed. In one embodiment, the collapsible structure includes a plurality of hinges and a plurality of panels. The plurality of panels are swingably connected by the plurality of hinges so as to form at least one arch when the collapsible structure is in an erected state and so as to become at least one stack of the plurality of panels in a collapsed state. The panels allow for the collapsible structure to maintain its structural integrity when erected but to have a compact and transportable configuration when collapsed.

Abstract: Collapsible structures are disclosed. In one embodiment, the collapsible structure includes a plurality of hinges and a plurality of panels. The plurality of panels are swingably connected by the plurality of hinges so as to form at least one arch when the collapsible structure is in an erected state and so as to become at least one stack of the plurality of panels in a collapsed state. The panels allow for the collapsible structure to maintain its structural integrity when erected but to have a compact and transportable configuration when collapsed.

Abstract: Collapsible structures are disclosed. In one embodiment, the collapsible structure includes a plurality of hinges and a plurality of panels. The plurality of panels are swingably connected by the plurality of hinges so as to form at least one arch when the collapsible structure is in an erected state and so as to become at least one stack of the plurality of panels in a collapsed state. The panels allow for the collapsible structure to maintain its structural integrity when erected but to have a compact and transportable configuration when collapsed.

Abstract: An apparatus for testing an implement having an elongate shaft with a head end and a grip end, with a head attached to the head end. The apparatus may include a wind tunnel with a test cell adapted to receive the head of the implement and permit a range of unrestricted movement of the head within the test cell. The test cell includes an inlet and outlet for air flow and a portal or opening in a wall of the cell to which an elongate conduit is attached. The conduit extends in a direction substantially normal, or radial, to the direction of airflow. The conduit is adapted to receive the shaft of the implement, with the grip end of the implement extending beyond the far end of the conduit and into a clamp. The clamp is adapted to hold the grip end of the shaft in a fixed position.

Abstract: A target for use in photogrammetric analysis that does not distort the object to be analyzed has been developed. The target is formed by mixing a diffuse material with a solvent and then applying the mixture to the surface of the object to be analyzed. The object is then coated with a reflective material so that the diffuse material forms a reflective target suitable for use in photogrammetric analysis.

Abstract: A target for use in photogrammetric analysis that does not distort the object to be analyzed has been developed. The target is formed by mixing a diffuse material with a solvent and then applying the mixture to the surface of the object to be analyzed. The object is then coated with a reflective material so that the diffuse material forms a reflective target suitable for use in photogrammetric analysis.