摘要:
A wing, such as a wing for an unmanned aerial vehicle (UAV), includes a beam or box that can be selectively expanded from a collapsed condition, to increase the thickness of the wing. The beam may include a pair of plates that are close together when the beam is in a collapsed condition, and separate from one another to put the beam in an expanded condition. The plates may be substantially parallel to each other, and may have shape memory foam and/or resilient devices, such as coil springs, between them, in order to provide a force to separate the plates before, during, and/or after deployment of the wing. The expandable/collapsible beam may have a lock mechanism to lock it into place when the beam is in an expanded condition.
摘要:
Piezomagnetic, magneto-strictive, or electro-strictive material particles may also be distributed throughout the structural material of the structural member, which serve to amplify and otherwise enhance the signals from the piezoelectric material particles. The piezoelectric, electro-strictive, magneto-strictive, and/or piezomagnetic material particles may allow the structural member to exhibit an electrical and/or magnetic response to forces on the structural member, such as accelerations. This may allow the structural member to function as a force sensor or an accelerometer. Signals induced by such external forces or accelerations may be taken from the conductive pickups and used for various operations, for example, for arming a warhead of a missile or for triggering passenger safety features such as air bags in automobiles.
摘要:
A removable rack for supporting a reflector in an oven having a light source where the reflector focuses light emitted from the light source in a predetermined manner. The preferred removable rack is arranged and configured to support a mirror array therein where the entire rack can be removably fixed to the interior of the oven in which it will be used. The rack is preferably arranged and configured to releasably engage the mirror array therein. A method for replacing a reflector disposed in the internal portion of an oven having a light source comprising the steps of providing a removable support rack for releasably supporting the reflector removably fixed to an interior portion of an oven. A reflector can be replaced by removing a member, fixing the removable support rack to the interior portion of the oven and removing the removable support rack from the interior of the oven. The rack and the mirror arrays supported thereon can be removed from the oven collectively by disengaging fixing members fixing the rack to the oven interior. The mirrors can then be removed from the rack by disengaging a support portion of the rack, thereby releasing the mirrors.
摘要:
A container includes a housing and a cover which may be wholly or partially removed to open the container. A foil seal is used to seal the joint between the housing and the cover. The foil seal is internal to the container. The foil seal separates during opening of the cover, respective parts of the foil seal remaining with the housing and the cover. The foil seal may be a metal or metal-containing foil, for example being an aluminum, steel, or titanium foil, or a metalized plastic foil. A cutter, such as a serrated edge, may be positioned to facilitate cutting of the foil seal during cover opening. The container may be part of a seeker assembly with the housing being a seeker housing, and the cover being a removable or hinged cover that protects an optical seeker during some portions of flight, such as during launch of a spacecraft.
摘要:
A shape-changing structural member has a shape-changing material, such as a suitable foam material, for example a polymer foam capable of withstanding at least 300% strain or a metal alloy foam capable of withstanding at least 5% strain. Springs, such as one or more coil springs, provide structural support for the shape-changing material. The springs may also be used to provide forces to expand and contract the shape change material. The springs may include pairs of concentric springs, one inside of another. The concentric springs may surround an underlying skeleton structure that supports the shape-changing material and/or aids in changing the shape of the material. The concentric springs may or may not be wrapped around the underlying skeleton structure. Multiple springs or pairs of springs may be coupled together using a sheet metal connector.
摘要:
A polymer is formed into the shape of a one-piece composite part and then solidified by curing, setting, hardening or otherwise solidifying the polymer to form a shaped polymer form having a shape that does not draw. Composite material is laid up on the form and solidified to from the composite part. The rigidity required of the form to lay up the composite part can he provided by operating in the polymer form's glassy state, forming the shaped polymer form with a hollow core and placing a rigid insert designed to draw inside the hollow core with the polymer form in its elastomeric state or through a combination of both. In its elastomeric state the form becomes pliable (without relaxing to a different memorized shape) and can he drawn out of the one-piece composite part. Because the shape of the form does not draw, the form deforms as it is drawn. If used, the rigid insert is drawn out prior to removing the shaped polymer form. Upon removal, the polymer form in its elastomeric state returns to its original shape. The form may be used once and thrown away or reused to form multiple composite parts of the same shape.
摘要:
A laminated wing structure includes at least one layer of metal material and at least one layer of a shape memory polymer (SMP) material. The SMP is heated to a temperature in its glass transition band Tg to roll the wing around the air vehicle into a stored position. The metal layer(s) must be thin enough to remain below its yield point when rolled up. In preparation for launch, the SMP material is thermally activated allowing the strain energy stored in the layer of metal material to return the wing to its deployed position at launch. Once deployed, the SMP cools to its glassy state. The SMP material may be reinforced with fiber to form a polymer matrix composite (PMC). SMP may be used to provide shear strain relief for multiple metal layers. By offloading the motive force required to return the wing to its original deployed position from the SMP to the metal, the polymer does not acquire a permanent set and the wing may be deployed accurately.
摘要:
A method of evaluating material properties of polymeric materials includes making one or more material samples or slabs, with each of the samples or slabs having a pair of material layers in contact with one another. The layers are layers of organic matrix polymer material that have different characteristics from each other, for example having a difference in composition and/or cure characteristics. Characteristics of the test slabs and the interface between the layers can be determined by examining curvatures of the test slabs. A number of samples may be made up having the same material in a first layer, and range of different materials in the respective second layers. The range may cover a range of various material compositions and/or cure characteristics.
摘要:
A nose cone formed from a shape memory alloy (SMA) having a recoverable strain of at least 2% collapses about the dome for storage, deploys at launch to protect the sensor dome and reduce drag during atmospheric flight and is shed to allow sensing for terminal maneuvers. The SMA is shape-set at elevated temperatures in its Austenite phase with a memorized shape having a radius of curvature greater than that of the sensor dome to reduce aerodynamic drag. The temperature is reduced and the SMA collapsed to conform to the curvature of the sensor dome within the recoverable strain for storage. A first mechanism is configured to return the collapsed SMA to its memorized shape at launch or prior to going supersonic. In one embodiment, the SMA is stored below its Martensite finish temperature in a temperature-induced Martensite phase in which case the mechanism heats the SMA above the Austenite finish temperature to return the material to its memorized shape. In another embodiment, the SMA is stored above its Austenite finish temperature in which case collapsing the SMA places the material in a strain-induced Martensite phase. The mechanism holds the collapsed SMA in place and the releases the stored energy allowing the SMA to return to the memorized shape.
摘要:
A shape-changing structure has a superelastic metal foam structural member that changes shape (morphs) to change configuration of the structure. The superelastic metal foam structural member changes shape while maintaining a continuous outer surface, with the continuous metal foam material inside the outer surface expanding, contracting, or otherwise changing shape. The superelastic metal foam material may be heated above a transition temperature to allow it to change shape, and then cooled to cause it to increase in strength, more easily maintaining its new shape. The superelastic metal foam material may be a suitable alloy, for example a nickel titanium alloy, that exhibits superelastic (pseudoelastic) behavior. The superelastic metal foam material may be a shape memory alloy material that returns to a set shape upon moderate heating. The superelastic metal elastic foam structural member may be heated either by an internal heat source or by external heating.