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Our work introduces a simple strategy for tailoring hierarchical anisotropy in microactuators using thermoresponsive liquid crystalline elastomers, thereby enabling versatile multimodal actuation.
Micro shutter array (MSA) is a programmable optical spatial filtering device fabricated by MEMS technology, which was originally developed for James Webb Space Telescope to enable multi-object spectroscopy. Next Generation Micro Shutter Array (NGMSA) is an effort to improve JWST MSA by eliminating macroscopic actuation magnet and using electrostatic force to achieve simple and reliable instrument that can support NASA’s multiple future missions. We have been fabricating NGMSA with design inherited from JWST, however the legacy design is not friendly for electrostatic actuation because applied force direction on the moving shutter blade is different. We use COMSOL AC/DC module’s electrostatics feature to understand electrostatic force applied on an individual shutter within a range of motion and study new candidate designs. Also, structural mechanics module is used to study torsion bar’s restoration force.
A soft buckling linear actuator is described, including: a plurality of substantially parallel bucklable, elastic structural components each having its longest dimension along a first axis; and a plurality of secondary structural components each disposed between and bridging two adjacent bucklable, elastic structural components; wherein every two adjacent bucklable, elastic structural components and the secondary structural components in-between define a layer comprising a plurality of cells each capable of being connected with a fluid inflation or deflation source; the secondary structural components from two adjacent layers are not aligned along a second axis perpendicular to the first axis; and the secondary structural components are configured not to buckle, the bucklable, elastic structural components are configured to buckle along the second axis to generate a linear force, upon the inflation or deflation of the cells. Methods of actuation using the same are also described.
A soft buckling linear actuator is described, including: a plurality of substantially parallel bucklable, elastic structural components each having its longest dimension along a first axis; and a plurality of secondary structural components each disposed between and bridging two adjacent bucklable, elastic structural components; wherein every two adjacent bucklable, elastic structural components and the secondary structural components in-between define a layer comprising a plurality of cells each capable of being connected with a fluid inflation or deflation source; the secondary structural components from two adjacent layers are not aligned along a second axis perpendicular to the first axis; and the secondary structural components are configured not to buckle, the bucklable, elastic structural components are configured to buckle along the second axis to generate a linear force, upon the inflation or deflation of the cells. Methods of actuation using the same are also described.
Combined attenuator and latch stops and latches in place a given mass which is to be moved a discrete distance to effect a desired condition. This device is used in a retraction actuator driven by a pyrotechnic thruster, and can be tailored to meet specific design requirements.
A hybrid electromechanical actuator has two different types of electromechanical elements, one that expands in a transverse direction when electric power is applied thereto and one that contracts in a transverse direction when electric power is applied thereto. The two electromechanical elements are (i) disposed in relation to one another such that the transverse directions thereof are parallel to one another, and (ii) mechanically coupled to one another at least at two opposing edges thereof. Electric power is applied simultaneously to the elements.
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Wake losses from neighboring plants may become a major factor in wind plant design and control as additional plants are constructed in areas with high wind resource availability. Because plant wakes span a large range of physical scales, from turbine rotor diameter to tens of kilometers, it is unclear whether conventional wake models or turbine control strategies are effective at the plant scale. Wake steering and axial induction control are evaluated in the current work as means of reducing the impact of neighboring wind plants on power and levelized cost of electricity. FLOw Redirection and Induction in Steady State (FLORIS) simulations were performed with the Gauss–Curl Hybrid and TurbOPark wake models as well as two operation and maintenance models to investigate control setpoint sensitivity to wake representation and economic factors. Both wake models estimate losses across a range of atmospheric conditions, although the wake loss magnitude is dependent on the wake model. Annual energy production and levelized cost of electricity are driven by wind direction frequency, with frequently aligned plants experiencing the greatest losses. However, both wake steering and axial induction are unable to mitigate the impact of upstream plants. Wake steering is constrained by plant geometry, since wake displacement is much less than the plant wake width, while axial induction requires curtailing the majority of turbines in upstream plants. Individual turbine strategies are limited by their effective scale and model representation. New wake models that include plant-scale physics are needed to facilitate the design of effective plant wake control strategies.
Abstract not provided.
Nalu-Wind is part of the ExaWind code suite.
Graphical data are presented on the X-axis transfer function tests. For Volume 1, see .
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Explore the source record for details and available documents.