Abstract: A vehicle wiper assembly includes a wiper blade having a length, and an active material disposed along the length of the wiper blade and coupled thereto. The active material includes a shape memory alloy material with a crystallographic phase that is changeable between austenite and martensite, and is elastically deformable and operatively applies a spring force against a portion of the wiper blade when the crystallographic phase is martensite.

Abstract: A vehicle wiper assembly includes a wiper blade having a length, and an active material disposed along the length of the wiper blade and coupled thereto. The active material includes a shape memory alloy material with a crystallographic phase that is changeable between austenite and martensite, and is elastically deformable and operatively applies a spring force against a portion of the wiper blade when the crystallographic phase is martensite.

Abstract: A vent assembly is disposed within an interior space of a vehicle for opening and closing fluid communication between the interior space and an exterior of the vehicle. The vent assembly includes a housing defining a plurality of openings and a plurality of vanes disposed in the openings. An actuator mechanism moves the vanes between an open position and a closed position, and includes a shaped memory alloy (SMA) member for actuating the vanes between the open and closed positions. The SMA member is activated when a hatch of the vehicle is opened to move the vanes into the open position and thereby open fluid communication between the interior space and the exterior to alleviate excessive air pressure buildup during closure of the hatch.

Abstract: A drain plug assembly that has particular application for sealing a drain hole in a battery compartment on a vehicle. The plug assembly includes a plug that inserted into the drain hole and a cover covering the plug. The plug assembly also includes a first shape memory alloy (SMA) wire having ends attached to the cover and a middle portion attached to the plug and a second SMA wire having ends attached to the cover and a middle portion attached to the plug. The plug assembly also includes a mechanical hinge attached to the plug and the cover, wherein the first SMA wire is actuated to flip the hinge to position the plug in a closed position to close the drain hole and the second SMA wire is actuated to flip the hinge to position the plug in an open position to open the drain hole.

Abstract: Some on-vehicle devices, such as air dams, air spoilers, and HVAC system baffles, may have movable components that are pulled from one position to another by shrinkage of a linear shape memory alloy (SMA) actuator. Upon an activation signal, the shrinkage of the SMA actuator occurs when it is resistance heated by an electrical current. It is found that useful information concerning the overall intended operation of the on-vehicle device may be obtained by computer analysis of the temporal variation of both current flow through the actuator and its electrical resistance as it is heated to perform its function in the device. A comparison of present current flow and variation of resistance, during activation of the device, with prescribed stored values can reveal malfunction of components of the device as it is being used, in place, on the vehicle.

Abstract: A transmission fluid circuit includes a transmission, a cooler, and a valve. The valve includes a housing, a spool and an actuator. The spool is movable inside the housing between a first position and a second position. The actuator includes a smart material configured to be activated in response to the temperature of the fluid exhibiting at least a first temperature such that the actuator is in a first state. The smart material is configured to be deactivated in response to the fluid being a sufficient number of degrees less than the first temperature such that the actuator is in a second state. The fluid flows from the housing to the transmission and from the transmission the cavity when the spool is in the first position. The fluid flows from the housing to the cooler and from the cooler to the transmission when the spool is in the second position.

Abstract: A method of testing a shape memory alloy (SMA) actuated device includes cyclically operating the device. The method further includes determining a number of cycles in a functional life of the device based on observations of the device during the cyclical operation. The functional life is a range of consecutive cycles of operation of the device beginning with a first cycle during which the device performs within a specified limit. The functional life is immediately followed by a cycle during which the device performs outside of the specified limit. The method still further includes applying a progressive substitution sub-process to identify an opportunity to increase the number of cycles in the functional life of the device.

Abstract: A transmission fluid circuit for regulating the flow of a fluid includes a transmission, a cooler, and a valve. The valve includes a housing, a spool, and an actuator including a smart material. The spool is movable inside the housing between a first position and a second position. The smart material is configured to be in an activated state in response to the fluid exhibiting at least a first temperature and to be in a deactivated state in response to the fluid being a sufficient number of degrees less than the first temperature. The fluid flows from the housing to the transmission and from the transmission to the housing when the spool is in the first position. The fluid flows from the housing to the cooler, from the cooler to the transmission, and from the transmission to the housing when the spool is in the second position.

Abstract: Mechanical devices powered by Shape Memory Alloy (SMA) wires or other linear elements offer advantages in automotive applications. Such SMA-powered devices are commonly reliable and long-lived but have a finite lifetime. Measurements of the electrical resistivity of an SMA element during operation of the element may be related to the remaining lifetime of the element. Because operation of SMA elements is promoted by heating the element, usually by passage of an electric current, the resistivity measurements, and hence assessment of SMA element operation, may be made without interruption to the operation of the SMA-powered device and without addition of dedicated sensors.

Abstract: A drain plug assembly that has particular application for sealing a drain hole in a high voltage battery compartment on a vehicle. The plug assembly includes a plug that inserted into the drain hole. The plug assembly further includes a return spring coupled to the plug and causing the plug to be biased into the drain hole. The plug assembly also includes at least one shape memory alloy device coupled to the plug and a support structure. The SMA device receives an electrical current that causes the device to contract and move the plug out of the drain hole against the bias of the return spring.

Abstract: A method of controlling an energy harvesting system that converts excess thermal energy into mechanical energy and includes a Shape Memory Alloy (SMA) member, includes obtaining current operational parameters of the energy harvesting system, such as a maximum temperature, a minimum temperature and a cycle frequency of the SMA member. The current operational parameters are compared to a target operating condition of the energy harvesting system to determine if the current operational parameters are within a pre-defined range of the target operating condition. If the current operational parameters are not within the pre-defined range of the target operating condition, then a heat transfer rate to, a heat transfer rate from or a cycle frequency of the SMA member is adjusted to maintain operation of the energy harvesting system within the pre-defined range of the target operating condition to maximize efficiency of the energy harvesting system.

Abstract: Shape memory alloy (SMA) actuating elements are commonly simpler and of lower mass than alternative actuator designs and may find particular application in the transportation industry. Such SMA-powered devices are usually reliable and long-lived but the phase transformations which occur in the SMA alloy and are responsible for its utility are not totally reversible. This irreversibility, a consequence of irrecoverable strain, may progressively degrade the long-term actuator performance as the irrecoverable strain accumulates over many operating cycles. Methods and devices for compensating for these effects and extending the useful cycle life of SMA actuators are described.

Abstract: An assembly for and method of reinforcing interconnection between an active material wire actuator, such as a shape memory alloy wire, and structure, includes the generation and engagement of an enlarged formation affixed to or integrally formed with the actuator.

Abstract: An inlet, positioned to access the flow of air passing around and under a moving vehicle, may draw in air which is conveyed through a duct and discharged to cool a brake on a vehicle. The inlet has a closure. The closure is opened and closed on demand by a temperature-operated actuator incorporating an active or smart material under the direction of a controller. In embodiments, a sensor, suitably positioned to sense a temperature representative of the brake temperature, communicates the sensed brake temperature to the controller. The controller may respond to the sensed brake temperature, by triggering operation of the actuator. Typically the closure is opened to allow passage of cooling air to the brake when the sensed brake temperature exceeds, or is anticipated to exceed, a predetermined temperature.

Abstract: A method for detecting a mechanical overload condition of an energized linear actuator to prevent commanding an activation signal to the linear actuator that may mechanically overload the linear actuator includes monitoring feedback variation of a movable element associated with the linear actuator including monitoring a present feedback signal of the movable element, monitoring a previous feedback signal of the movable element, comparing the present feedback signal and the previous feedback signal and determining the feedback variation based on the comparing. The feedback variation is compared to a feedback variation threshold. An input signal associated with the activation signal for controlling the linear actuator is monitored and the input signal compared to an input signal threshold. The electrical overload condition is detected when the feedback variation is less than the feedback variation threshold and the input signal is greater than the input signal threshold.

Abstract: An equivalent power method for reducing the effects of voltage variation during at least one active material actuation event, includes determining an applied real output based on the ideal voltage of a voltage source, the corresponding ideal output of a controller, and a measured real voltage, and for providing voltage out of bounds compensation, by further determining a difference based on the maximum available power output of the controller during said at least one event, and applying the difference to determine the applied real output during subsequent event(s).

Abstract: A vent assembly is disposed within an interior space of a vehicle for opening and closing fluid communication between the interior space and an exterior of the vehicle. The vent assembly includes a housing defining a plurality of openings and a plurality of vanes disposed in the openings. An actuator mechanism moves the vanes between an open position and a closed position, and includes a shaped memory alloy (SMA) member for actuating the vanes between the open and closed positions. The SMA member is activated when a hatch of the vehicle is opened to move the vanes into the open position and thereby open fluid communication between the interior space and the exterior to alleviate excessive air pressure buildup during closure of the hatch.

Abstract: A baffle controller for moving a baffle disposed within an HVAC outlet housing between an open position and a closed position to control airflow through an HVAC outlet in a vehicle includes a Shape Memory Alloy (SMA) actuator that is controlled and actuated by an electrical signal. The SMA actuator rotates a main lever that rotates a valve plate. The valve plate is attached to the baffle such that the baffle rotates with the valve plate. The baffle controller may include a position biasing device that increases a position holding ability of the baffle controller, and a cut-off switch that interrupts the electrical signal to the SMA actuator to prevent over-rotating the baffle.

Abstract: A releasable connection connects a first component to a second component. The second component includes and is manufactured from a Shape Memory Polymer (SMP), and defines a pocket. The first component includes a portion disposed within the pocket. The pocket is deformed from an initial shape permitting insertion of the portion into the pocket to assembly the releasable connection into a connected shape wherein the pocket is deformed to secure the first component relative to the second component. The pocket is transformed from the initial shape into the connected shape by heating the SMP material of the second component to a switching temperature. Re-heating the SMP second component to the switching temperature returns the pocket back to the initial shape from the connected shape to disassembly the releasable connection.

Abstract: A system for controlling an active material actuator includes an active material actuator configured to actuate when energized, a power supply configured to supply electrical power, and a control circuitry including a plurality of circuits and configured to selectively establish an electrical connection between the active material actuator and the power supply upon receipt of an activation signal. The control circuitry is configured to de-energize at least one of the circuits when no activation signal is received by the control circuitry in order to minimize parasitic current drawn from the power supply.