摘要:
A power-off hold element for operating in cooperation with an actuator is disclosed. The power-off hold element comprises a material having selectively adjustable rigidity wherein a position or shape of said material is adjustable when energy is applied to increase the temperature of the material above a temperature where the material becomes flexible and the material is rigid in a position or shape when the temperature of the material decreases below the temperature where the material becomes flexible. Also disclosed is a process for operating a power-off hold element for operating in cooperation with an actuator.
摘要:
One nanostructured actuator embodiment includes an actuation region between electrical contacts. The actuation region includes an elastic matrix with embedded nanocomposite layered structures, which have inorganic material layers with pillared organic material structures between the inorganic material layers responsive to the surface acidity of the inorganic material layers. The elastic matrix allows transport of species for changing the surface acidity. A separator region is between the electrical contacts. A proton generation region capable of reversible electrochemical production and elimination of protons is provided, which may be a hydrogen storage material located on a side of the separator region opposite the actuation region, which may include metal hydride, or metal hydroxide. Alternatively, it may include an electrolytic solution and conductive particles within the elastic matrix for in situ electrochemical generation of an acid/base. The conductive particles may include carbon nanotubes, metal fibers, and/or metal nanoparticles. The nanocomposite structures may be generally aligned with a direction of work in the elastic matrix.
摘要:
A reversible energy absorbing assembly including a shape memory foam disposed within an interior region, wherein the shape memory foam is adapted to expand to an expanded configuration in response to fluid communication with a fluid source. The shape memory foam is a material selected from the group consisting of shape memory alloys and shape memory polymers. Once expanded, the assembly effectively absorbs kinetic energy of an object upon impact with the assembly. The shape memory foam can be thermally activated to restore the original configuration of the energy absorbing assembly. Methods of operating the energy absorbing assembly are also disclosed.
摘要:
A metrology system includes a laser, a position sensitive detector array, a first collimator, a second collimator, and a mirror. The position sensitive detector array and the first collimator are positioned at a reference point. The second collimator and the mirror are positioned at a point target at a distance from the reference point. A laser beam is alternately provided to the first collimator and the second collimator by optical fiber. The position sensitive detector array measures position data from a first laser crosshair generated by the first collimator and from a second laser crosshair generated by the second collimator. By alternating the activation of the first collimator and the second collimator it is possible to measure 5 degrees-of-freedom for the point target. A metrology system processing unit provides analog data processing. The metrology system that is suitable for, but not limited to, facilitating active compensation of large spacecraft structures.
摘要:
An airflow control device comprises a body and an active material in operative communication with the body. The active material, such as shape memory material, is operative to change at least one attribute in response to an activation signal. The active material can change its shape, dimensions and/or stiffness producing a change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness to control vehicle airflow to better suit changes in driving conditions such as weather, ground clearance and speed, while reducing maintenance and the level of failure modes. As such, the device reduces vehicle damage due to inadequate ground clearance, while increasing vehicle stability and fuel economy. An activation device, controller and sensors may be employed to further control the change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness of the device. A method for controlling vehicle airflow selectively introduces an activation signal to initiate a change of at least one feature of the device that can be reversed upon discontinuation of the activation signal.
摘要:
Reversibly deployable energy absorbing assemblies for impact management generally include a translatable first element, a rigid support structure and a second element having one end fixedly attached to the rigid support structure and an other end fixedly attached to the translatable first element. The second elements are adapted to plastically deform along a predefined buckling path. The predefined buckling path may be uni-modal or multi-modal depending on the desired application and/or impact conditions. Also disclosed herein are methods for operating the energy absorbing assemblies.
摘要:
An airflow control device comprises a body and an active material in operative communication with the body. The active material, such as shape memory material, is operative to change at least one attribute in response to an activation signal. The active material can change its shape, dimensions and/or stiffness producing a change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness to control vehicle airflow to better suit changes in driving conditions such as weather, ground clearance and speed, while reducing maintenance and the level of failure modes. As such, the device reduces vehicle damage due to inadequate ground clearance, while increasing vehicle stability and fuel economy. An activation device, controller and sensors may be employed to further control the change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness of the device. A method for controlling vehicle airflow selectively introduces an activation signal to initiate a change of at least one feature of the device that can be reversed upon discontinuation of the activation signal.
摘要:
Door closure assist assemblies that assist in providing a final closing motion generally includes an extender portion comprised of an active material adapted to linearly expand in response to an activation signal and a releasable fastener having one component in movable communication with the extender portion and a second component attached to the other selected one of the door and doorframe. During operation, the door closure assist assembly provides the final closing action.
摘要:
An airflow control device comprises a body and an active material in operative communication with the body. The active material, such as shape memory material, is operative to change at least one attribute in response to an activation signal. The active material can change its shape, dimensions and/or stiffness producing a change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness to control vehicle airflow to better suit changes in driving conditions such as weather, ground clearance and speed, while reducing maintenance and the level of failure modes. As such, the device reduces vehicle damage due to inadequate ground clearance, while increasing vehicle stability and fuel economy. An activation device, controller and sensors may be employed to further control the change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness of the device. A method for controlling vehicle airflow selectively introduces an activation signal to initiate a change of at least one feature of the device that can be reversed upon discontinuation of the activation signal.
摘要:
An airflow control device comprises a body and an active material in operative communication with the body. The active material, such as shape memory material, is operative to change at least one attribute in response to an activation signal. The active material can change its shape, dimensions and/or stiffness producing a change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness to control vehicle airflow to better suit changes in driving conditions such as weather, ground clearance and speed, while reducing maintenance and the level of failure modes. As such, the device reduces vehicle damage due to inadequate ground clearance, while increasing vehicle stability and fuel economy. An activation device, controller and sensors may be employed to further control the change in at least one feature of the airflow control device such as shape, dimension, location, orientation, and/or stiffness of the device. A method for controlling vehicle airflow selectively introduces an activation signal to initiate a change of at least one feature of the device that can be reversed upon discontinuation of the activation signal.