System and method for controlling shape memory alloy actuators
AssigneeUnited Technologies Corporation
InventorPrabir Barooah
Life of this patent
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Abstract
A system and method of controlling a shape memory alloy (SMA) actuator comprises supplying maximum control voltage to an SMA actuator where an object having a position to be controlled by the SMA actuator were to move toward a target position upon supply of non-zero control voltage, and the instantaneous actual position of the object is at a distance above a predetermined threshold from the target position. A variably controlled voltage is supplied to the SMA actuator between the maximum voltage and about zero voltage where the object to be controlled were to move toward the target position upon supply of the variably controlled voltage, and the instantaneous actual position of the object is at a distance below the predetermined threshold from the target position.
Claims12
A method of controlling a shape memory alloy (SMA) actuator, comprising the steps of:
- supplying maximum control voltage to an SMA actuator where an object having a position to be controlled by the SMA actuator were to move toward a target position upon supply of non-zero control voltage, and the instantaneous actual position of the object is at a distance above a predetermined threshold from the target position;
- and
- supplying a variably controlled voltage to the SMA actuator between the maximum voltage and about zero voltage where the object to be controlled were to move toward the target position upon supply of the variably controlled voltage, and the instantaneous actual position of the object is at a distance below the predetermined threshold from the target position.
A method of controlling an SMA actuator, comprising the steps of:
- providing an SMA actuator for moving an object to a predetermined target position;
- supplying maximum control voltage to the SMA actuator where an object having a position to be controlled by the SMA actuator were to move toward a target position upon supply of non-zero control voltage, and the instantaneous actual position of the object is at a distance above a predetermined threshold from the target position;
- and
- supplying a variably controlled voltage to the SMA actuator between the maximum voltage and about zero voltage where the object to be controlled were to move toward the target position upon supply of the variably controlled voltage, and the instantaneous actual position of the object is at a distance below the predetermined threshold from the target position.
An SMA actuator control system comprising:
- an SMA actuator including SMA wires and at least one position sensor, the SMA actuator to be coupled to an object having a position to be moved by the SMA actuator;
- means for supplying maximum control voltage to the SMA actuator where the object having a position to be controlled by the SMA actuator were to move toward a target position upon supply of a non-zero control voltage, and the instantaneous actual position of the object is at a distance above a predetermined threshold from the target position;
- and
- means for supplying a variably controlled voltage to the SMA actuator between the maximum voltage and about zero voltage where the object to be controlled were to move toward the target position upon supply of the variably controlled voltage, and the instantaneous actual position of the object is at a distance below the predetermined threshold from the target position.
Dependencies are inferred from the claim text.