摘要:
A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof whereas the hook portion includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. The hook elements are formed of a material or have configurations that provide a shape changing capability and/or change in flexural modulus property to the hook elements. In this manner, the shape and/or flexural modulus of the hook elements can be remotely changed to provide a reduction in the shear and/or pull-off forces.
摘要:
A mechanical, active crash pulse management structure for providing modification of crash pulse, wherein the structure has a dormant (initial) state volume, but then in the event of a crash, timely expands into a much larger deployed volume for providing management of an expectant crash energy. The preferred crash energy management structure is a before expansion honeycomb celled material brick, wherein expansion of the honeycomb brick is in a plane transverse to the cellular axis of the cells thereof, and crash crush is intended to be parallel to the cellular axis. In the event of a crash, either an active or passive activation mechanism is provided for causing expansion of honeycomb celled material.
摘要:
A magnetorheological damper device is provided having an increased shear interface area per unit volume of device, which enhances the stroking force of the damper. The damper generally includes a thrust shaft comprising an external threaded surface in threaded communication with a sealed housing, wherein at least one end of the thrust shaft extends from the housing; a plurality of rotors and stators alternatingly arranged in the housing, wherein the plurality of rotors comprise a planar surface with a centrally located aperture that is rotatably engaged with the threaded surface of the thrust shaft, wherein the plurality of stators is fixedly attached to the housing and comprises a centrally located aperture dimensioned to accommodate vertical movement of the thrust shaft and a planar surface substantially parallel to the planar surface of the at least one rotor, and wherein alternating stators comprises a permanent magnet or an electromagnet; and a magnetorheological fluid disposed in a space defined by the plurality of rotors and stators.
摘要:
A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof whereas the hook portion includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. The hook elements are formed of a material or have configurations that provide a shape changing capability and/or change in flexural modulus property to the hook elements. In this manner, the shape and/or flexural modulus of the hook elements can be remotely changed to provide a reduction in the shear and/or pull forces.
摘要:
An energy absorbing assembly includes a covering; and a shape memory material in operative communication with the covering, wherein the shape memory material has a first shape attached to an underside of the covering and is operative to change to a second shape in response to an activation signal. The second shape of the shape memory material can cause the covering to expand or expand and detach from a surrounding surface medium. The energy absorbing assembly is used to absorb kinetic energy of an object impacting the assembly. Methods of operating the assembly are also disclosed.
摘要:
A mechanical, active crash pulse management structure for providing modification of crash pulse, wherein the structure has a dormant (initial) state volume, but then in the event of a crash, timely expands into a much larger deployed volume for providing management of an expectant crash energy. The preferred crash energy management structure is a before expansion honeycomb celled material brick, wherein expansion of the honeycomb brick is in a plane transverse to the cellular axis of the cells thereof, and crash crush is intended to be parallel to the cellular axis. In the event of a crash, either an active or passive activation mechanism is provided for causing expansion of honeycomb celled material.
摘要:
A magnetorheological damper device is provided having an increased shear interface area per unit volume of the device, which enhances the stroking force of the damper. The damper generally includes a cylindrically shaped housing; a magnetorheological fluid disposed in the cylindrically shaped housing; a piston assembly disposed within the cylindrically shaped housing in sliding engagement with the cylindrically shaped housing defining a first chamber and a second chamber, wherein the piston assembly comprises a plurality of cylindrically shaped fluid passageways extending from the first chamber to the second chamber, and an electromagnet; and a power supply in electrical communication with the electromagnet.
摘要:
A releasable fastening system for retaining two surfaces at each other or disengaging the two surfaces from each other comprises a first electrode disposed at a first surface, a second electrode disposed at a second surface, and a polymer film disposed between the first and second electrode, and an electrolyte disposed in electrical communication with the first electrode, the polymer film, and the second electrode. A volume of the polymer film is controllably variable to cause the retention of the first surface at the second surface. A method of releasably fastening adjacently-positioned surfaces comprises disposing a first electrode at a first surface, disposing a second electrode at a second surface, and increasing the volume of an electrolyte disposed in electrical communication with the first electrode and the second electrode to cause the retention of the first surface at the second surface.
摘要:
Processes for providing rapid release of a hook and loop type releasable fastener system comprise preconditioning the releasable fastener system to effect rapid release. In this manner, minimal energy and time is required for disengagement of the releasable fastener system.
摘要:
A motor vehicle body including a plurality of vertical pillars defining therebetween a plurality of door frames for access to a passenger compartment of the vehicle body, a plurality of doors supported by pairs of hinges on the front vertical pillar of each door frame for pivotal movement between closed and open positions, and a light weight side impact protection barrier characterized by high elongational stiffness and high strain-at-failure. The light weight barrier may be employed alone or in combination with a horizontal door beam and includes a synthetic cable in the door made from a plurality of helically braided bundles of fibers selected from a group of fibers consisting of aramid fibers and liquid crystal polymer fibers characterized by a strain-at-failure exceeding about 3%. The synthetic cable includes attachments to the front and rear pillars of the door frame when the door is closed. The synthetic cable is very stiff in tension to suppress intrusion into the passenger compartment and has a failure mode characterized by serial or sequential failure of individual ones of the fibers rather than simultaneous failure of all of the fibers.