A backward wave amplifier（BWA） in a terahertz regime with a novel slow-wave structure（SWS） composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SW...A backward wave amplifier（BWA） in a terahertz regime with a novel slow-wave structure（SWS） composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SWS possesses good performance and is compatible with micro-fabrication technologies. The dispersion and interaction impedance of the multipin SWS are presented. The stopbands of the modes cling together in a Brillouim zone. The SWS has a high interaction impedance that is suitable for the interaction of multi cylindrical beams. The design, which is based on three parallel pins supporting the wave–beam interaction with four cylindrical beams, is verified by three-dimensional particle-in-cell simulations. A BWA with the central frequency at 340 GHz is demonstrated, and the output power is more than 100 mW.A tuning frequency range of 15 GHz（333–348 GHz） is obtained with a gain of more than 20 dB.展开更多
A novel slotted helix slow-wave structure （SWS） is proposed to develop a high power, wide-bandwidth, and high reliability millimeter-wave traveling-wave tube （TWT）. This novel structure, which has higher heat capa...A novel slotted helix slow-wave structure （SWS） is proposed to develop a high power, wide-bandwidth, and high reliability millimeter-wave traveling-wave tube （TWT）. This novel structure, which has higher heat capacity than a conven- tional helix SWS, evolves from conventional helix SWS with three parallel rows of rectangular slots made in the outside of the helix tape. In this paper, the electromagnetic characteristics and the beam-wave interaction of this novel structure operating in the Ka-band are investigated. From our calculations, when the designed beam voltage and beam current are set to be 18.45 kV and 0.2 A, respectively, this novel circuit can produce over 700-W average output power in a frequency range from 27.5 GHz to 32.5 GHz, and the corresponding conversion efficiency values vary from 19% to 21.3%, and the maximum output power is 787 W at 30 GHz.展开更多
A watt-class backward wave oscillator is proposed, using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz. Firstly, the dispersion curve of the sine waveguide i...A watt-class backward wave oscillator is proposed, using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz. Firstly, the dispersion curve of the sine waveguide is calculated, then, the oscillation frequency and operating voltage of the device are predicted and the circuit transmission loss is calculated. Finally, the particle-in-cell simulation method is used to forecast its radiation performance. The results show that this novel backward wave oscillator can produce over 1-W continuous wave power output in a frequency range from 210 GHz to 230 GHz. Therefore, it will be considered as a very promising high-power millimeter-wave to terahertz-wave radiation source.展开更多
The variational method is applied to calculate the dispersion characteristics of disc-loaded waveguide slow-wave structures. The parameters describing the waveguide discontinuities in disc-loaded waveguide are calcula...The variational method is applied to calculate the dispersion characteristics of disc-loaded waveguide slow-wave structures. The parameters describing the waveguide discontinuities in disc-loaded waveguide are calculated by the variational method. Then the dispersion characteristics of slow-wave structures are obtained using lossless microwave quadrupole theory. Good agreement was observed between results of the Variational method and those of field matching method and high frequency structure simulator. In the case of broad band, results of the variational method are better than those of field matching method.展开更多
Micromachined comb-drive electrostatic resonators with folded-cantilever beams were designed and fabricated. A combination of Rayleigh＇s method and finite-element analysis was used to calculate the resonant frequency...Micromachined comb-drive electrostatic resonators with folded-cantilever beams were designed and fabricated. A combination of Rayleigh＇s method and finite-element analysis was used to calculate the resonant frequency drift as we adjusted the device geometry and material parameters. Three micromachined lateral resonant resonators with different beam widths were fabricated. Their resonant frequencies were experimentally measured to be 64.5,147.2, and 255.5kHz, respectively, which are in good agreement with the simulated resonant frequency. It is shown that an improved frequency performance could be obtained on the poly 3C-SiC based device structural material systems with high Young＇s modulus.展开更多
A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabr...A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabricated in SOI substrate by using a bulk-and-surface mixed silicon micromachining process. As demonstrated by experiment, the novel driving structure can actuate the mirror to achieve large-range continuous rotation as well as spontaneous 90°rotation induced by the pull-in effect. The continuous rotating range of the micromirror is increased to about 46° at an increased yielding voltage. The measured yielding voltages of the mirrors with torsional springs of 1 and 0.5μm in thickness are 390 - 410V and 140 - 160V, respectively. The optical insertion loss has also been measured to be --1.98dB when the mirror serves as an optical switch.展开更多
This paper investigates the properties of traveling wave-beam interaction in a rectangular helix traveling-wave-tube （TWT） for a solid sheet electron beam. The ＂hot＂ dispersion equation is obtained by means of the...This paper investigates the properties of traveling wave-beam interaction in a rectangular helix traveling-wave-tube （TWT） for a solid sheet electron beam. The ＂hot＂ dispersion equation is obtained by means of the self-consistent field theory. The small signal analysis,which includes the effects of the beam parameters and slow-wave structure （SWS） parameters,is carried out by theoretical computation. The numerical results show that the bandwidth and the small-signal gain of the rectangular helix TWT increase as the beam current increases;and the beam voltage not obviously influences the small signal gain. Among different rectangular helix structures,the small-signal gain increases as the width of the rectangular helix SWS increases,however,the bandwidth decreases whether structure parameters a and L or ψ and L are fixed or not.In addition,a comparison of the small-signal gain of this structure with a conventional round helix is made.The presented analysis will be useful for the design of the TWT with a rectangular helix circuit.展开更多
The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interactio...The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interaction impedance of this structure are derived and numerically calculated. The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS. Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed. It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained, indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction. The small signal gain property is investigated for ensuring the improvement of bandwidth. Meanwhile, with comparable dispersion characteristics, the transverse section dimension of this novel structure is much smaller than that of conventional one, which indicates an available way to reduce the weight of traveling-wave tube.展开更多
This paper studies the dispersion characteristics of a modified photonic band-gap slow-wave structure with an open boundary by simulation and experiment. A mode launcher with a wheel radiator and a coupling probe is p...This paper studies the dispersion characteristics of a modified photonic band-gap slow-wave structure with an open boundary by simulation and experiment. A mode launcher with a wheel radiator and a coupling probe is presented to excite a pure TM01-like mode. The cold test and simulation results show that the TM01-like mode is effectively excited and no parasitic modes appear. The dispersion characteristics obtained from the cold test are in good agreement with the calculated results.展开更多
Lightweight structures are widely used across different industry sectors.However,they get easily excited by external influences,such as vibrations.Undesired high vibration amplitudes can be avoided by shifting the str...Lightweight structures are widely used across different industry sectors.However,they get easily excited by external influences,such as vibrations.Undesired high vibration amplitudes can be avoided by shifting the structural eigenfrequencies,which can be achieved adapting the structural design considering optimisation procedures and structures primarily inspired by diatoms.This procedures has been applied to the development process of a girder structure installed in a synchrotron radiation facility to support heavy magnets and other components.The objective was to design a 2.9 m long girder structure with high eigenfrequencies,a high stiffness and a low mass.Based on a topology optimisation result,a parametric beam–shell model including biologically inspired structures(e.g.,Voronoi combs,ribs,and soft and organic-looking transitions)was built up.The subsequent cross-sectional optimisation using evolutionary strategic optimisation revealed an optimum girder structure,which was successfully manufactured using the casting technology.Eigenfrequency measurements validated the numerical models.Future changes in the specifications can be implemented in the bio-inspired development process to obtain adapted girder structures.展开更多
[Background]Traveling-wave tubes(TWTs)are widely applied in radar,imaging,and military systems owing to their excellent amplification characteristics.Miniaturization and integration are critical to the future of TWTs,...[Background]Traveling-wave tubes(TWTs)are widely applied in radar,imaging,and military systems owing to their excellent amplification characteristics.Miniaturization and integration are critical to the future of TWTs,with multi-channel slow-wave structures(SWSs)forming the foundation for their realization in high-power vacuum electronic devices.[Purpose]To provide design insights for multi-channel TWTs and simultaneously enhance their output power,a W-band folded-waveguide TWT with dual electron beams and H-plane power combining was proposed.[Methods]Three-dimensional electromagnetic simulations in CST were conducted to verify the highfrequency characteristics,electric field distribution,and amplification performance of the proposed SWS,thereby confirming the validity of the design.[Results]Results indicate that the designed TWT achieves a transmission bandwidth of 10 GHz.With an electron beam voltage of 17.9 kV and a current of 0.35 A,the output power reaches 450 W at 94 GHz,corresponding to an efficiency of 7.18%and a gain of 23.5 dB.Moreover,under fixed beam voltage and current,the TWT delivers over 200 W output power across 91–99 GHz,with a 3 dB bandwidth of 91–98.5 GHz.The particle voltage distribution after modulation further validates the mode analysis.[Conclusions]These results demonstrate the feasibility of compact dual-beam power-combining structures and provide useful guidance for the design of future multi-channel TWTs.展开更多
The synthesis and structure-property correlation of poly（N-（2-hydroxypropyl） methacrylamide） （PHPMA） conjugates with various architectures including random, block, branched or star-like structures and compositio...The synthesis and structure-property correlation of poly（N-（2-hydroxypropyl） methacrylamide） （PHPMA） conjugates with various architectures including random, block, branched or star-like structures and compositions have been thoroughly explored. However, related synthesis and structure-property data are still lacking for comb-like PHPMA. In this work, we report the synthesis of comb-like PHPMA copolymer-doxorubicin （DOX） conjugates with different backbone/side-chain lengths and location of drug moieties. Well-defined comb-like PHPMA-DOX conjugates are obtained via the combination of controlled radical polymerization and fractional precipitation techniques. The influences of structural factors on the biological properties such as cellular uptake, blood circulation and tumor accumulation have been investigated. Long blood circulation and efficient tumor accumulation can be achieved by proper control of the comb number, length and location of drug moieties. These facile comb-like structures possess great potentials in future theranostics for brachytherapy or surgical navigation.展开更多
Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of...Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of polymer structure. At proper copolymer composition, lithium concentration and pendant length, the ion conductivity reaches 7.0×10^(-5)S/cm at ambient temperature, together with improved mechanical strength. The ion transport in the polymer media is assisted by segmental relaxation, which is confirmed both by the consistency between ion conductivity and T_g and by the study of TSC.展开更多
Comb-drive devises have been widely applied in many fields. However, the application of high frequency sensor, such as rocket chamber, still remains problems. In this work, a finite element code was used for the desig...Comb-drive devises have been widely applied in many fields. However, the application of high frequency sensor, such as rocket chamber, still remains problems. In this work, a finite element code was used for the design, optimization and visualization of a comb drive accelerator. In the simulation results, the post-optimization design has high performance in high frequency oscillation operating environment. The optimization is based on the ideal eigenfrequency and Nelder-Mead method. The 3-D working conditions are realized by testing and comparing the time and frequency domain of pre-optimized and optimized design whose frequency ranges from 2000 Hz to 5000 Hz. Finally, the electric potential and capacitance in comb drive are visualized, which shows the better electric signals and displacements.展开更多
In this study, we research about comb-drive micro-structure, which is a MEMS device used to measure velocities and accelerations. To ensure the accuracy and visualization of the result, we simulate the dynamics of the...In this study, we research about comb-drive micro-structure, which is a MEMS device used to measure velocities and accelerations. To ensure the accuracy and visualization of the result, we simulate the dynamics of the comb drive?using COMSOL Multiphysics, meanwhile introducing the concept of re-meshing.?We aim to find the optimal comb-drive-building material, which can provide the device with the most desirable first eigenfrequency. According to the optimization process, silver is the most suitable construction material. Afterwards, the electric responses of both the optimized device and the pre-optimized one are analyzed in frequency domain and stationary study. We conclude that the capacitance change is positively related to frequency in a linear manner, and that the optimized device has a larger increment of both displacement and capacitance per unit of frequency change than the pre-optimized one, showing that the optimization of material realizes our goal of enhancing electrical performance.展开更多
基金Project supported by the National Basic Research Program of China(Grant No.2014CB339801)the National High Technology Research and Development Program of China(Grant No.G060104012AA8122007B)
文摘A backward wave amplifier（BWA） in a terahertz regime with a novel slow-wave structure（SWS） composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SWS possesses good performance and is compatible with micro-fabrication technologies. The dispersion and interaction impedance of the multipin SWS are presented. The stopbands of the modes cling together in a Brillouim zone. The SWS has a high interaction impedance that is suitable for the interaction of multi cylindrical beams. The design, which is based on three parallel pins supporting the wave–beam interaction with four cylindrical beams, is verified by three-dimensional particle-in-cell simulations. A BWA with the central frequency at 340 GHz is demonstrated, and the output power is more than 100 mW.A tuning frequency range of 15 GHz（333–348 GHz） is obtained with a gain of more than 20 dB.
基金Project supported by the National Natural Science Foundation of China(Grant No.61271029)the Natural Science Key Laboratory Foundationthe Natural Science Fund for Distinguished Young Scholars of China(Grant No.61125103)
文摘A novel slotted helix slow-wave structure （SWS） is proposed to develop a high power, wide-bandwidth, and high reliability millimeter-wave traveling-wave tube （TWT）. This novel structure, which has higher heat capacity than a conven- tional helix SWS, evolves from conventional helix SWS with three parallel rows of rectangular slots made in the outside of the helix tape. In this paper, the electromagnetic characteristics and the beam-wave interaction of this novel structure operating in the Ka-band are investigated. From our calculations, when the designed beam voltage and beam current are set to be 18.45 kV and 0.2 A, respectively, this novel circuit can produce over 700-W average output power in a frequency range from 27.5 GHz to 32.5 GHz, and the corresponding conversion efficiency values vary from 19% to 21.3%, and the maximum output power is 787 W at 30 GHz.
基金Project supported by the National Natural Science Foundation for Distinguished Young Scholars of China (Grant No. 61125103)the National Natural Science Foundation of China (Grant Nos. 60971038 and 60971031)the Fundamental Research Funds for the Central Universities,China (Grant No. ZYGX2009Z003)
文摘A watt-class backward wave oscillator is proposed, using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz. Firstly, the dispersion curve of the sine waveguide is calculated, then, the oscillation frequency and operating voltage of the device are predicted and the circuit transmission loss is calculated. Finally, the particle-in-cell simulation method is used to forecast its radiation performance. The results show that this novel backward wave oscillator can produce over 1-W continuous wave power output in a frequency range from 210 GHz to 230 GHz. Therefore, it will be considered as a very promising high-power millimeter-wave to terahertz-wave radiation source.
文摘The variational method is applied to calculate the dispersion characteristics of disc-loaded waveguide slow-wave structures. The parameters describing the waveguide discontinuities in disc-loaded waveguide are calculated by the variational method. Then the dispersion characteristics of slow-wave structures are obtained using lossless microwave quadrupole theory. Good agreement was observed between results of the Variational method and those of field matching method and high frequency structure simulator. In the case of broad band, results of the variational method are better than those of field matching method.
文摘Micromachined comb-drive electrostatic resonators with folded-cantilever beams were designed and fabricated. A combination of Rayleigh＇s method and finite-element analysis was used to calculate the resonant frequency drift as we adjusted the device geometry and material parameters. Three micromachined lateral resonant resonators with different beam widths were fabricated. Their resonant frequencies were experimentally measured to be 64.5,147.2, and 255.5kHz, respectively, which are in good agreement with the simulated resonant frequency. It is shown that an improved frequency performance could be obtained on the poly 3C-SiC based device structural material systems with high Young＇s modulus.
文摘A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabricated in SOI substrate by using a bulk-and-surface mixed silicon micromachining process. As demonstrated by experiment, the novel driving structure can actuate the mirror to achieve large-range continuous rotation as well as spontaneous 90°rotation induced by the pull-in effect. The continuous rotating range of the micromirror is increased to about 46° at an increased yielding voltage. The measured yielding voltages of the mirrors with torsional springs of 1 and 0.5μm in thickness are 390 - 410V and 140 - 160V, respectively. The optical insertion loss has also been measured to be --1.98dB when the mirror serves as an optical switch.
基金Project supported in part by the National Natural Science Foundation of China (Grant No 60532010)the Talent Fund of Chinese Education Administration
文摘This paper investigates the properties of traveling wave-beam interaction in a rectangular helix traveling-wave-tube （TWT） for a solid sheet electron beam. The ＂hot＂ dispersion equation is obtained by means of the self-consistent field theory. The small signal analysis,which includes the effects of the beam parameters and slow-wave structure （SWS） parameters,is carried out by theoretical computation. The numerical results show that the bandwidth and the small-signal gain of the rectangular helix TWT increase as the beam current increases;and the beam voltage not obviously influences the small signal gain. Among different rectangular helix structures,the small-signal gain increases as the width of the rectangular helix SWS increases,however,the bandwidth decreases whether structure parameters a and L or ψ and L are fixed or not.In addition,a comparison of the small-signal gain of this structure with a conventional round helix is made.The presented analysis will be useful for the design of the TWT with a rectangular helix circuit.
基金Project supported in part by the National Natural Science Foundation of China (Grant No. 60971038)in part by the Fundamental Research Funds for Central Universities,China (Grant No. ZYGX2009Z003)
文摘The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interaction impedance of this structure are derived and numerically calculated. The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS. Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed. It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained, indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction. The small signal gain property is investigated for ensuring the improvement of bandwidth. Meanwhile, with comparable dispersion characteristics, the transverse section dimension of this novel structure is much smaller than that of conventional one, which indicates an available way to reduce the weight of traveling-wave tube.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10975036 and 61071018)the Guangxi Natural Science Foundation,China (Grant No. 2010GXNSFB013049)
文摘This paper studies the dispersion characteristics of a modified photonic band-gap slow-wave structure with an open boundary by simulation and experiment. A mode launcher with a wheel radiator and a coupling probe is presented to excite a pure TM01-like mode. The cold test and simulation results show that the TM01-like mode is effectively excited and no parasitic modes appear. The dispersion characteristics obtained from the cold test are in good agreement with the calculated results.
基金This study was financially supported by the Innovationsfonds from the Alfred Wegener Institute,Helmholtz Centre for Polar andMarine Research(AWI)and by the Deutsches Elektronen-Synchrotron(DESY),a research centre of the Helmholtz Association,christian.hamm@awi.de。
文摘Lightweight structures are widely used across different industry sectors.However,they get easily excited by external influences,such as vibrations.Undesired high vibration amplitudes can be avoided by shifting the structural eigenfrequencies,which can be achieved adapting the structural design considering optimisation procedures and structures primarily inspired by diatoms.This procedures has been applied to the development process of a girder structure installed in a synchrotron radiation facility to support heavy magnets and other components.The objective was to design a 2.9 m long girder structure with high eigenfrequencies,a high stiffness and a low mass.Based on a topology optimisation result,a parametric beam–shell model including biologically inspired structures(e.g.,Voronoi combs,ribs,and soft and organic-looking transitions)was built up.The subsequent cross-sectional optimisation using evolutionary strategic optimisation revealed an optimum girder structure,which was successfully manufactured using the casting technology.Eigenfrequency measurements validated the numerical models.Future changes in the specifications can be implemented in the bio-inspired development process to obtain adapted girder structures.
基金National Key Research and Development Program of China(2022YFF0707602)National Natural Science Foundation of China(62471097,62471115,62471101)National Natural Science Foundation of Sichuan(2025ZNSFSC0537)。
文摘[Background]Traveling-wave tubes(TWTs)are widely applied in radar,imaging,and military systems owing to their excellent amplification characteristics.Miniaturization and integration are critical to the future of TWTs,with multi-channel slow-wave structures(SWSs)forming the foundation for their realization in high-power vacuum electronic devices.[Purpose]To provide design insights for multi-channel TWTs and simultaneously enhance their output power,a W-band folded-waveguide TWT with dual electron beams and H-plane power combining was proposed.[Methods]Three-dimensional electromagnetic simulations in CST were conducted to verify the highfrequency characteristics,electric field distribution,and amplification performance of the proposed SWS,thereby confirming the validity of the design.[Results]Results indicate that the designed TWT achieves a transmission bandwidth of 10 GHz.With an electron beam voltage of 17.9 kV and a current of 0.35 A,the output power reaches 450 W at 94 GHz,corresponding to an efficiency of 7.18%and a gain of 23.5 dB.Moreover,under fixed beam voltage and current,the TWT delivers over 200 W output power across 91–99 GHz,with a 3 dB bandwidth of 91–98.5 GHz.The particle voltage distribution after modulation further validates the mode analysis.[Conclusions]These results demonstrate the feasibility of compact dual-beam power-combining structures and provide useful guidance for the design of future multi-channel TWTs.
基金supported by the National Natural Science Foundation of China(Nos.51503013,51390481,21774008and 81472412)supported by the Fundamental Research Funds for the Central Universities(Nos.ZY1519 and XK1701)+1 种基金the long-term subsidy mechanism from the Ministry of Financethe Ministry of Education of PRC for BUCT
文摘The synthesis and structure-property correlation of poly（N-（2-hydroxypropyl） methacrylamide） （PHPMA） conjugates with various architectures including random, block, branched or star-like structures and compositions have been thoroughly explored. However, related synthesis and structure-property data are still lacking for comb-like PHPMA. In this work, we report the synthesis of comb-like PHPMA copolymer-doxorubicin （DOX） conjugates with different backbone/side-chain lengths and location of drug moieties. Well-defined comb-like PHPMA-DOX conjugates are obtained via the combination of controlled radical polymerization and fractional precipitation techniques. The influences of structural factors on the biological properties such as cellular uptake, blood circulation and tumor accumulation have been investigated. Long blood circulation and efficient tumor accumulation can be achieved by proper control of the comb number, length and location of drug moieties. These facile comb-like structures possess great potentials in future theranostics for brachytherapy or surgical navigation.
文摘Poly (oligoether methacrylate-co-acrylonitrile) s, P (MEOn- AN), with oligoether pendants of different lengths were synthesized and the ion conduction property of their Li-salt complexes was studied as the function of polymer structure. At proper copolymer composition, lithium concentration and pendant length, the ion conductivity reaches 7.0×10^(-5)S/cm at ambient temperature, together with improved mechanical strength. The ion transport in the polymer media is assisted by segmental relaxation, which is confirmed both by the consistency between ion conductivity and T_g and by the study of TSC.
文摘Comb-drive devises have been widely applied in many fields. However, the application of high frequency sensor, such as rocket chamber, still remains problems. In this work, a finite element code was used for the design, optimization and visualization of a comb drive accelerator. In the simulation results, the post-optimization design has high performance in high frequency oscillation operating environment. The optimization is based on the ideal eigenfrequency and Nelder-Mead method. The 3-D working conditions are realized by testing and comparing the time and frequency domain of pre-optimized and optimized design whose frequency ranges from 2000 Hz to 5000 Hz. Finally, the electric potential and capacitance in comb drive are visualized, which shows the better electric signals and displacements.
文摘In this study, we research about comb-drive micro-structure, which is a MEMS device used to measure velocities and accelerations. To ensure the accuracy and visualization of the result, we simulate the dynamics of the comb drive?using COMSOL Multiphysics, meanwhile introducing the concept of re-meshing.?We aim to find the optimal comb-drive-building material, which can provide the device with the most desirable first eigenfrequency. According to the optimization process, silver is the most suitable construction material. Afterwards, the electric responses of both the optimized device and the pre-optimized one are analyzed in frequency domain and stationary study. We conclude that the capacitance change is positively related to frequency in a linear manner, and that the optimized device has a larger increment of both displacement and capacitance per unit of frequency change than the pre-optimized one, showing that the optimization of material realizes our goal of enhancing electrical performance.
