摘要:
The present invention relates to a method and system for sensing and controlling the strain induced in a magnetic shape memory alloy element, and to a magnetic shape memory alloy actuator and sensor. The actuating element (5a) is operated by a control unit (10) having an input control signal (6a) and an input signal (7a) representative of the strain of the actuating element, consisting of a magnetic shape memory alloy. The strain of the actuating element (5a) is determined by measuring its internal electrical resistance, and the control of the same is provided by applying a magnetic field across it, having a magnitude corresponding to the input control signal (6a) and the feedback (7a) information, thereby altering the length of said actuating element (5a) to achieve the desired actuation.
摘要:
An autofocus actuator for camera modules and control method thereof, the autofocus actuator incorporating a shape memory alloy wire as actuating element, at least 4 spheres as sliding aids, and including a return elastic element mounted between an autofocus housing and a lens carrier and exerting a force only in the optical axis direction.
摘要:
Actuation and control of the deployment of a polymeric memory-shape material on a wellbore device on a downhole tool may be accomplished by treating a compacted or compressed polymeric memory-shape material with a deployment fluid to lower its Tg and/or decrease its rigidity, thereby softening the polymeric shape-memory material at a given temperature and triggering its expansion or recovery at a lower temperature. Alternatively, the deployment of the compacted or compressed polymeric memory-shape material may be prevented or inhibited by shielding the material with an environment of a fluid that does not substantially lower its Tg, decrease its rigidity or both, and then subsequently contacting the material with a deployment fluid.
摘要:
A system and methods for base excitation of moderately high vibration of micro-cantilevers are disclosed. A micro-cantilever may be coupled to one or more actuators adjacent its base. The actuators may comprise bulk materials, bridges, or formed wires that expand and contract by application of electric currents, due to, for example, the effect of electro-thermal heating or piezoelectric effects. Single actuators or an array of actuators may be placed around the micro-cantilever to oscillate it and apply actuation pulses. The system and methods, and adjustments of the geometrical parameters, may be performed to yield a nominal natural frequency in the system. The excitation of actuators with signals corresponding to the natural frequency may induce resonance in the system and may result in high amplitude vibrations and displacement of the cantilever tip of the micro-cantilever. Various architectures of the actuators may be implemented to stimulate different frequencies of the beam and induce displacement in different direction and amplitudes.
摘要:
The invention provides an energy recovery system comprising a first Shape Memory Alloy (SMAs) or Negative the bundle Thermal Expansion (NTE) core and adapted to convert movement of the core into energy in response to a first temperature. Various embodiments are disclosed to include cascaded core arrangements, preheating/cooling of cores and how to decrease the time of reaction for the shape memory alloy in an efficient manner.
摘要:
An SMA actuator arrangement is assembled using a strut element shaped to comprise a sacrificial strut body and crimp tabs held apart by the sacrificial strut body. A SMA wire is laid across the crimp tabs which are folded and pressed to form crimps holding the SMA wire. The crimps are then attached to static and moving parts, after which the sacrificial strut body is removed. The method allows the crimping to be performed without hindrance from the static and moving parts, the sacrificial strut body holding the relative locations of the crimps prior to attachment.
摘要:
A system for heating a shape memory alloy (SMA) actuator may include an SMA actuator, a smart susceptor, a plurality of induction coils, and a control module. The SMA actuator may have at least one layup. The SMA actuator may be selectively heated to a transition temperature. The smart susceptor may be in thermal contact with the at least one layup of the SMA actuator. The induction heating coils may be configured to receive an alternating current and generate a magnetic field based on the alternating current. The magnetic field may create an eddy current in at least one of the SMA actuator and the smart susceptor to heat the SMA actuator to the transition temperature. The control module may be configured to drive the alternating current supplied to the induction heating coils.
摘要:
A direction controlled service apparatus may include a mounting assembly (14), a housing assembly (12) configured to operably connect to the mounting assembly (14), the housing assembly (12) being movable with respect to the mounting assembly (14), and a plurality of actuators (16) connected between the mounting assembly (14) and the housing assembly (12), each actuator of the plurality of actuators (16) being configured to contract upon a current being applied to the actuator to rotate the housing assembly (12) with respect to the mounting assembly (14).
摘要:
Ventil (10) zum selektiven Öffnen einer Fluidleitung, insbesondere in einem Satellitenantriebssystem, umfassend: ein Einlasselement (12), einen Auslassbereich (16), ein Verschlusselement (20), das in einer Ausgangsposition eine fluidische Verbindung zwischen dem Einlasselement (12) und dem Auslassbereich (16) blockiert, und ein Aktorelement (40), das dazu ausgebildet, sich an dem Verschlusselement (20) abzustützen, wobei das Aktorelement (40) ein zumindest von dem Einlasselement (12) abweichendes Wärmeausdehnungsverhalten aufweist, und wobei sich das Aktorelement (40) entlang einer Längsachse (L1) des Einlasselements (12) erstreckt und dazu ausgebildet ist, sich ab Erreichen eines vorbestimmten Erwämungsgrades mit einer derartigen Kraft an dem Verschlusselement (20) abstützten, dass das Verschlusselement (20) aus seiner Ausgangsposition bewegt wird und eine fluidische Verbindung zwischen dem Einlasselement (12) und dem Auslassbereich (16) ermöglicht.