摘要:
Active texturing systems adapted for selectively and reversibly modifying the texture of a surface utilizing a plurality of discrete mechanisms in communication with the reconfigurable structure.
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.
摘要:
A method of improving the speed and consistency of response of a shape memory alloy actuator under varying ambient and operating conditions. The method includes probing the shape memory alloy by periodically determining an electric signal strength at which it will undergo forward or reverse phase transformation, while avoiding actual phase transformation; priming the shape memory alloy by bringing it close to phase transformation; initiating phase transformation; and maintaining the shape memory alloy in the phase transformed state. The electric signal strength at which the shape memory alloy will undergo phase transformation is determined by identifying a cusp feature in the electric resistance of the shape memory alloy which closely precedes phase transformation.
摘要:
An active material actuator assembly is provided having first and second active material components operatively connected to a movable member. Movement of the movable member is modulated, which may be due to activation of the first and second active material components being at least partially temporally distinct or the active material components differing in at least one characteristic affecting movement.
摘要:
Systems for and methods of determining at least one mid-stroke position of an active material actuated load by causing a stress induced rapid change in electrical resistance within the active material element, or modifying an ancillary circuit, when the load is at the mid-stroke position(s).
摘要:
In one embodiment, a cover system can comprise: a cover and an active material component in operable communication with the cover. The active material component can comprise an active material that enables the deployment and retraction of the cover.
摘要:
An active material actuator assembly is provided having first and second active material components operatively connected to a movable member. Movement of the movable member is modulated, which may be due to activation of the first and second active material components being at least partially temporally distinct or the active material components differing in at least one characteristic affecting movement.
摘要:
A shape memory alloy (SMA) heat engine includes a first rotatable pulley, a second rotatable pulley, and an SMA material disposed about the first and second rotatable pulleys and between a hot region and a cold region. A method of starting and operating the SMA heat engine includes detecting a thermal energy gradient between the hot region and the cold region using a controller, decoupling an electrical generator from one of the first and second rotatable pulleys, monitoring a speed of the SMA material about the first and second rotatable pulleys, and re-engaging the driven component if the monitored speed of the SMA material exceeds a threshold. The SMA material may selectively change crystallographic phase between martensite and austenite and between the hot region and the cold region to convert the thermal gradient into mechanical energy.