- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Quantum Rangefindng
摘要： Transformer parasitics such as leakage inductance and self-capacitance are rarely calculated in advance during the design phase, because of the complexity and huge analytical error margins caused by practical winding implementation issues. Thus, choosing one transformer architecture over another for a given design is usually based on experience or a trial and error approach. This paper presents analytical expressions for calculating leakage inductance, self-capacitance, and ac resistance in transformer winding architectures (TWAs), ranging from the common noninterleaved primary/secondary winding architecture, to an interleaved, sectionalized, and bank winded architecture. The calculated results are evaluated experimentally, and through finite-element simulations, for an RM8 transformer with a turns ratio of 10. The four TWAs such as, noninterleaved and nonsectioned, noninterleaved and sectioned, interleaved and nonsectioned, and interleaved and sectioned, for an EF25 transformer with a turns ratio of 20, are investigated and practically implemented. The best TWA for an RM8 transformer in a high-voltage bidirectional flyback converter, used to drive an electro active polymer based incremental actuator, is identified based on the losses caused by the transformer parasitics. For an EF25 transformer, the best TWA is chosen according to whether electromagnetic interference due to the transformer interwinding capacitance, is a major problem or not.
关键词： energy efficiency,switch-mode power converters,transformer winding architectures,Actuator,high-voltage dc–dc converters,high-voltage transformer,transformer parasitics
更新于2025-09-19 17:13:59
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[IEEE 2019 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD) - Ottawa, ON, Canada (2019.7.8-2019.7.12)] 2019 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD) - Simulation of Lateral Near- and Far-Field Profiles of Gain-Guided High-Power Semiconductor Lasers
摘要： The conversion of electrical to mechanical power on a sub-centimeter scale is a key technology in many microsystems and energy harvesting devices. In this paper, we present a type of a capacitive energy conversion device that uses capillary pressure and electrowetting to reversibly convert electrical power to hydraulic power. These microhydraulic actuators use a high surface-to-volume ratio to deliver high power at a relatively low voltage with an energy conversion efficiency of over 65%. The capillary pressure generated grows linearly with shrinking capillary diameter, as does the frequency of actuation. We present the pressure, frequency, and power scaling properties of these actuators and demonstrate that power density scales up as the inverse capillary diameter squared, leading to high-efficiency actuators with a strength density exceeding biological muscle. Two potential applications for microhydraulics are also demonstrated: soft-microrobotics and energy harvesting.
关键词： electrowetting,Microhydraulics,porous materials,energy conversion,electrocapillary,microsystems,soft robotics,energy harvesting,microrobotics,actuator,microfluidics,PDMS
更新于2025-09-19 17:13:59
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Fabrication of Large Single Crystals for Pt-Based Linear Polymers with Controlled-Release and Photoactuator Performance
摘要： Preparation of large single crystals for linear polymers that are amenable to X-ray analysis is very challenging in polymer science. Herein, we employed a coordination driven self-assembly strategy to secure appropriate head-to-tail alignment of anthracene moieties, and for the first time obtained large-sized Pt-based linear polymer crystals through a [4+4] cycloaddition of anthracene in a single-crystal to single-crystal fashion. Using X-ray diffraction analysis to precisely determine polymer crystal structure, we revealed that both the polymerisation and depolymerisation steps proceed via a stable intermediate. Taking advantage of the temperature-dependent slow depolymerization, the afforded Pt-based linear polymer showed potential as a sustained release anticancer drug platform. Furthermore, utilizing the reversible contraction effect of unit-cell volume upon irradiation or heating, the stimuli-responsive crystals were hybridized with polyvinylidene fluoride to obtain a ‘smart material’ with outstanding photoactuator performance. This work not only provides a new approach to prepare metal-containing linear polymer crystals, but also broadens their potential applications towards drug controlled-release and actuator functions.
关键词： Actuator,Sustained release,Topochemical polymerization,Polymer crystals,Linear polymer
更新于2025-09-19 17:13:59
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[IEEE 2018 IEEE International Conference on Information and Automation (ICIA) - Wuyishan, China (2018.8.11-2018.8.13)] 2018 IEEE International Conference on Information and Automation (ICIA) - Optimization design of multi-sided reflecting prism in laser line scanning imaging system
摘要： A passive thermal micro-actuator with large area specific work and large displacement, fabricated of electroplated nickel on a silicon substrate is presented. The actuation relies on the thermal expansion of beams in a V-shaped geometry. Two V-shaped beam stacks are aligned opposite to each other and are coupled to a lever transmission. The actuator exhibits low energy losses due to the deformation of the structure and can efficiently convert the thermally induced elastic energy into mechanical work. An analytical model considers these thermally induced mechanical energies and the energy losses caused by the deformation of the material. The calculated deflections are compared with the measured ones and results of finite-element method simulations. The presented actuator operates completely passive, relies only on temperature changes of the surrounding environment, and exhibits a measured temperature-dependent linear deflection coefficient of 1.48 μm/K with a simulated blocking force of 57 μN/K. The structure occupies an area of 2135 × 1831 μm2 and the area specific work is calculated to be 21.7 μJ/K2/m2, beating state of the art thermal actuators. As proof-of-concept, a passive micro-electro-mechanical systems temperature threshold sensor is fabricated, featuring the actuator and a bistable beam that switches between two stable positions when a specific threshold temperature is exceeded.
关键词： Micro mechanical system,electroplated nickel,V-shaped,energy efficient,passive thermal actuator
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Bulk Power System Dynamics with Varying Levels of Synchronous Generators and Grid-Forming Power Inverters
摘要： The conversion of electrical to mechanical power on a sub-centimeter scale is a key technology in many microsystems and energy harvesting devices. In this paper, we present a type of a capacitive energy conversion device that uses capillary pressure and electrowetting to reversibly convert electrical power to hydraulic power. These microhydraulic actuators use a high surface-to-volume ratio to deliver high power at a relatively low voltage with an energy conversion efficiency of over 65%. The capillary pressure generated grows linearly with shrinking capillary diameter, as does the frequency of actuation. We present the pressure, frequency, and power scaling properties of these actuators and demonstrate that power density scales up as the inverse capillary diameter squared, leading to high-efficiency actuators with a strength density exceeding biological muscle. Two potential applications for microhydraulics are also demonstrated: soft-microrobotics and energy harvesting.
关键词： microsystems,electrocapillary,soft robotics,PDMS,actuator,energy conversion,microfluidics,electrowetting,energy harvesting,porous materials,Microhydraulics,microrobotics
更新于2025-09-16 10:30:52
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The light-controlled actuator driven by the novel opto-electrostatic hybrid driving method based on PLZT ceramic
摘要： The lanthanum-doped lead zirconate titannate (PLZT) ceramic has shown its potential applications as light-controlled micro actuators activated by ultraviolet light for the photovoltaic e?ect in the ?eld of micro-driven. Aiming to the slow response of photostriction of PLZT ceramic, the primary purpose of this article is to propose a light-controlled actuator with the novel opto-electrostatic hybrid driving based on PLZT ceramic. The mathematical model of the proposed light-controlled actuator is established on basis of the anomalous photovoltaic e?ect model of PLZT ceramic. The actuation characteristics of the micro actuator are investigated based on the established mathematical model and the experiments of the photovoltage of PLZT ceramic. Furthermore, the actuation curves of the micro actuator driven by opto-electrostatic hybrid driving based on PLZT ceramic are acquired to verify the rationality and feasibility of the light-controlled micro actuator design. So according to the analysis and experimental results, the light-controlled actuator driven by the novel opto-electrostatic hybrid driving based on PLZT can conduct the e?ectively and precisely displacement control with fast response speed. In addition, the driving method based on the novel opto-electrostatic hybrid driving has advantages of non-contact control, remote control and no electromagnetic interference, etc.
关键词： PLZT,opto-electrostatic hybrid driving,micro actuator,light-controlled
更新于2025-09-12 10:27:22
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A frequency-tunable nanomembrane mechanical oscillator with embedded quantum dots
摘要： Hybrid systems consisting of a quantum emitter coupled to a mechanical oscillator are receiving increasing attention for fundamental science and potential applications in quantum technologies. In contrast to most of the presented works in this field, in which the oscillator eigenfrequencies are irreversibly determined by the fabrication process, we present here a simple approach to obtain frequency-tunable mechanical resonators based on suspended nanomembranes. The method relies on a micromachined piezoelectric actuator, which we use both to drive resonant oscillations of a suspended Ga(Al)As membrane with embedded quantum dots and to fine-tune their mechanical eigenfrequencies. Specifically, we excite oscillations with frequencies of at least 60 MHz by applying an AC voltage to the actuator and tune the eigenfrequencies by at least 25 times their linewidth by continuously varying the elastic stress state in the membranes through a DC voltage. The light emitted by optically excited quantum dots is used as a sensitive local strain gauge to monitor the oscillation frequency and amplitude. We expect that our method has the potential to be applicable to other optomechanical systems based on dielectric and semiconductor membranes possibly operating in the quantum regime.
关键词： nanomembrane,piezoelectric actuator,frequency-tunable,quantum dots,mechanical oscillator
更新于2025-09-12 10:27:22
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Automated Manufacturing of Mechatronic Parts by Laser-Based Powder Bed Fusion
摘要： The powder-bed-based laser beam melting process (L-PBF) has become one of the most reliable and popular additive manufacturing technologies in the field of industrial production of metal components. Moreover, it is constantly evolving to ensure lower costs due to higher productivity as well as to enable the processing of new materials, such as tungsten or copper-alloys. In terms of machine developments, a number of trends are observable. On the one hand, machines become able to produce multi-material parts with an arbitrary distribution of at least two different materials. Therefore, the existing powder delivery system must be adapted. As multiple approaches for doing so already exist, it must be decided which is the most suitable. On the other hand, a further goal is to integrate sensors or actuators automatically, to create structural parts with fully encapsulated electronic components. For this automated process, a pick-and-place concept must be developed and integrated into an existing L-PBF machine. To implement this automated process extension, several adjustments to the system must be implemented. This paper presents approaches for realising the described concepts and the first results of the adapted manufacturing processes.
关键词： smart parts,automated actuator integration,multi-material,powder bed fusion,additive manufacturing,L-PBF process enhancement,automated sensor integration,selective laser melting,SLM
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Tunable All-Fiber Laser for Remote Sensing of Methane Near 3.4 μm
摘要： The mid-infrared (MIR) region of the optical spectrum has drawn considerable scientific interest in the past few years. Indeed, several molecules relevant to medical or environmental conundrums exhibit strong absorption lines in this region: for instance, methane lines in the MIR are up to 100 times stronger than in the near-infrared [1]. In turn, fiber lasers have long stood as prime candidates for remote gas detection in outdoor environments, given their exemplary robustness, power scaling and beam quality. However, while several previous contributions have targeted methane bands under 3.3 μm in wavelength [2], little work has been done to push fiber laser detection tools past 3.4 μm, where methane absorption lines are mostly decoupled from the absorption spectra of water and other atmospheric constituents. This is especially relevant when probing CH4 through a gas mixture with relatively high water content, such as when studying gas emission from methane-rich thermokarst lakes in northern regions. To this end, we present a tunable all-fiber laser emitting near 3.43 μm and operating at high average power. The laser design (Fig. 1) is based on an all-fiber dual-pumping scheme [3], which combines core-pumping at 1976 nm with clad-pumping at 976 nm in a single-mode erbium-doped fluoride glass fiber to reach, in the present case, up to 3 W of output power at the desired wavelength. The laser cavity itself is delimited by two fiber Bragg gratings (FBG): a highly-reflective (HR) FBG at the input, which has a narrow bandwidth to dictate the laser wavelength, and a lowly-reflective (LR) FBG at the output, which has a large bandwidth to accommodate shifts of the HR FBG. Tuning of the laser cavity is achieved by mechanically stretching (i.e. lengthening) the HR FBG via the beam bending technique [4]. The HR FBG is nested within an Invar-based metallic groove and fixed using a polymer of sufficient elasticity, the groove is then deformed using a piezoelectric actuator (PA), allowing for rapid and precise wavelength tuning over a wavelength range of a few nanometers. Figure 2 compares normalized spectra of the laser emission at various commanding voltages for the PA along with the absorption spectrum of methane as given by the HITRAN database [1]. As can be seen on Fig.2, the presence of consecutive extrema (min-max) allows for quick referencing of the measurement during each tuning cycle. Early gas cell experiments and further engineering refinement show good promise for future deployment in northern regions by climate scientists.
关键词： methane,remote sensing,mid-infrared,piezoelectric actuator,fiber Bragg gratings,tunable all-fiber laser
更新于2025-09-12 10:27:22
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Fabrication of Large Single Crystals for Pt‐Based Linear Polymers with Controlled‐Release and Photoactuator Performance
摘要： Preparation of large single crystals for linear polymers that are amenable to X-ray analysis is very challenging in polymer science. Herein, we employed a coordination driven self-assembly strategy to secure appropriate head-to-tail alignment of anthracene moieties, and for the first time obtained large-sized Pt-based linear polymer crystals through a [4+4] cycloaddition of anthracene in a single-crystal fashion. Using X-ray diffraction analysis to precisely determine polymer crystal structure, we revealed that both the polymerisation and depolymerisation steps proceed via a stable intermediate. Taking advantage of the temperature-dependent slow depolymerization, the afforded Pt-based linear polymer showed potential as a sustained release anticancer drug platform. Furthermore, utilizing the reversible contraction effect of unit-cell volume upon irradiation or heating, the stimuli-responsive crystals were hybridized with polyvinylidene fluoride to obtain a ‘smart material’ with outstanding photoactuator performance. This work not only provides a new approach to prepare metal-containing linear polymer crystals, but also broadens their potential applications towards drug controlled-release and actuator functions.
关键词： Sustained release,Polymer crystals,Linear polymer,Topochemical polymerization,Actuator
更新于2025-09-11 14:15:04