A microactuator providing an output force and displacement in response to an increase in thermal energy is displosed. The microactuator may have a substantially straight expansion member with a first and a second end. The first end may be coupled to a base member, and the second end may be coupled to a shuttle. The expansion member is capable of elongating in a elongation direction. Elongation of the expansion member may urge the shuttle to translate in an output direction substantially different than the elongation direction. In certain embodiments, multiple expansion members are arrayed along one side of the shuttle to drive the shuttle against a surface. Alternatively, expansion members may be disposed on both sides of the shuttle to provide balanced output force. If desired, multiple microactuators may be linked together to multiply the output displacement and/or output force.
A micromechanism (104) with two unique, stable configurations is disclosed. The micromechanism (104) has a base member (120) and a shuttle (122) designed to move in linear fashion. The shuttle (122) is coupled to the base member (120) via a coupling (26) in which flexible members (50, 52) are placed under axial tension in addition to bending. The coupling (26) also has a compressive member (54) that is compressed as the flexible members (50, 52) are placed in tension. The shuttle (122) has a displacement between the stable configurations that is suitable for use with thermomechanical microactuators and microswitching applications. Such a micromechanism may have multiple couplings (26), which may be disposed on either side of the shuttle (122) and may be attached to multiple base members (120). An electric return signal may be applied to the micromechanism to thermally relax the couplings (26), thereby promoting the micromechanism (104) to return from the second stable configuration to the first stable configuration. Alternatively, a separate return actuator may be used.
The present invention provides systems and methods for conversion of thermal energy to electrical energy. The devices and methods according to the invention allow for efficient conversion of thermal energy to electrical power in a meso-to-micro scale device. In general, the present invention relates to a device for converting thermal energy to electrical energy comprising a working fluid contained within at least one region. The region is exposed to a thermal gradient and thermal energy is transferred through at least a first thermal energy-accepting layer for transferring thermal energy to the working fluid. At least one diaphragm is acted upon by the working fluid, which thermodynamically expands upon thermal energy being transferred thereto to flex the diaphragm. A mechanism is provided for converting the structural flexure of the diaphragm to electrical energy, along with at least one thermal energy transfer mechanism for transferring thermal energy from the working fluid through the diaphragm to cool the working fluid and cause thermodynamic contraction thereof. The thermodynamic cycle of heating and cooling the working fluid causes expansion and contraction thereof in turn causes cyclic flexure of the diaphragm in response to the device being exposed to thermal energy. The cyclic flexure of the diaphragm in conjunction with other structures produces the desired conversion to electrical energy.
An optical switch for routing signals includes a latch receiver connected to a waveguide that routes the signals and an actuator that includes an upper plate, a lower plate and a latch connected to the lower plate, the lower plate of the actuator moving vertically when power is applied to the lower plate, causing the latch to move vertically and engage the latch receiver. A latching system includes a switch that includes a latch formed to include an extension on one end of the latch, the latch being driven by power, a latch receiver that is formed to receive the latch and a controller that controls the extension of the latch to engage the latch receiver when the power is applied to the latch, and controls the extension of the latch to lock in place against the latch receiver when the power is removed from the latch.
An active hinge apparatus is disclosed which can be used to raise a micromechanical structure (e.g. a plate or micromirror) on a substrate. The active hinge apparatus utilizes one or more of teeth protruding outward from an axle which also supports the micromechanical structure on one end thereof. A rack is used to engage the teeth and rotate the axle to raise the micromechanical structure and tilt the structure at an angle to the substrate. Motion of the rack is provided by an actuator which can be a mechanically-powered actuator, or alternately an electrostatic comb actuator or a thermal actuator. A latch can be optionally provided in the active hinge apparatus to lock the micromechanical structure in an "erected" position.
A representative embodiment of the invention provides an infrared (IR) detector having a movable plate supported at an offset distance from a substrate by a suspension arm. In response to a temperature difference between the plate and the substrate generated by the incident IR radiation, the suspension arm deforms and changes the offset distance for the plate. In one embodiment, the suspension arm has three rod-shaped bimorph transducers that lie within a plane that is parallel to the substrate. The transducers are also parallel to one another, with the transducer that is attached to an anchor of the suspension arm being located between the two transducers that are attached to the plate.
