Dynamic characteristics of the resonant gyroscope are studied based on the Mathieu equation approximate solution in this paper.The Mathieu equation is used to analyze the parametric resonant characteristics and the ap...Dynamic characteristics of the resonant gyroscope are studied based on the Mathieu equation approximate solution in this paper.The Mathieu equation is used to analyze the parametric resonant characteristics and the approximate output of the resonant gyroscope.The method of small parameter perturbation is used to analyze the approximate solution of the Mathieu equation.The theoretical analysis and the numerical simulations show that the approximate solution of the Mathieu equation is close to the dynamic output characteristics of the resonant gyroscope.The experimental analysis shows that the theoretical curve and the experimental data processing results coincide perfectly,which means that the approximate solution of the Mathieu equation can present the dynamic output characteristic of the resonant gyroscope.The theoretical approach and the experimental results of the Mathieu equation approximate solution are obtained,which provides a reference for the robust design of the resonant gyroscope.展开更多
We theoretically investigate several parameters for the nuclear magnetic resonance gyroscope based on ^(133)C_(s–)^(129)Xe/^(131)Xe. For a cell containing a mixture of ^(133)Cs at saturated pressure, we inv...We theoretically investigate several parameters for the nuclear magnetic resonance gyroscope based on ^(133)C_(s–)^(129)Xe/^(131)Xe. For a cell containing a mixture of ^(133)Cs at saturated pressure, we investigate the optimal quenching gas(N_2) pressure and the corresponding pump laser intensity to achieve 30% ^(133)Cs polarization at the center of the cell when the static magnetic field B0 is 5 μT with different ^(129)Xe/^(131)Xe pressure. The effective field produced by spin-exchange polarized ^(129)Xe or ^(131)Xe sensed by ^(133)Cs can also be discussed in different^(129)Xe/^(131)Xe pressure conditions. Furthermore,the relationship between the detected signal and the probe laser frequency is researched. We obtain the optimum probe laser detuning from the D2(6~2S_(1/2)→ 6~2P_(3/2)) resonance with different ^(129)Xe/^(131)Xe pressure owing to the pressure broadening.展开更多
Integrated optical gyroscopes(IOGs)have been an efficient tool for numerous applications in various fields,including inertial navigation,flight control,and earthquake monitoring.Here,we review the progress of integrat...Integrated optical gyroscopes(IOGs)have been an efficient tool for numerous applications in various fields,including inertial navigation,flight control,and earthquake monitoring.Here,we review the progress of integrated optical gyroscopes based on two categories of integrated interferometric optical gyroscopes(IIOGs)and integrated resonant optical gyroscopes(IROGs).展开更多
Nuclear magnetic resonance gyroscope (NMRG) has the characteristics of high precision and miniaturization, and is one of the main applications of quantum technology in the field of navigation. The transverse relaxatio...Nuclear magnetic resonance gyroscope (NMRG) has the characteristics of high precision and miniaturization, and is one of the main applications of quantum technology in the field of navigation. The transverse relaxation time (T_(2)) of the xenon nuclear spin in the atomic cell of the NMRG directly affects the angular random walk of the gyro. Accurate and rapid measurement of T_(2) is conducive to further improvement of gyroscope. At present, for the measurement of T_(2), the schemes of two orthogonal lasers for pumping and detecting are usually used. By applying two fast-switching orthogonal static magnetic fields and a single beam of circularly polarized laser with corresponding wavelength to pump the atomic cell, the xenon nuclear macroscopic magnetic moment Larmor precession is generated. The cesium atoms parametric magnetometer in cell is formed to detect the free induction decay signal generated by nuclear spin precession of xenon atoms. The measurement of T_(2) by a single laser simplifies the measurement equipment compared with traditional method with two lasers. The experimental results show that the T_(2) of xenon atoms is more than 10 s, and the effects of temperature are studied, which lay the foundation for the subsequent improvement of gyro performance.展开更多
Based on the parametric resonance magnetometer(PRM)theory,this paper establishes an experimen-tal system of PRM.The experimental results are consistent with the theoretical predictions.A PRM has been developed with se...Based on the parametric resonance magnetometer(PRM)theory,this paper establishes an experimen-tal system of PRM.The experimental results are consistent with the theoretical predictions.A PRM has been developed with sensitivity of 0.5 pT/Hz^(1/2),which can detect the magnitude of residual magnetic field;furthermore,a proportion-integration-differentiation(PID)closed-loop magnetic compensation system of the residual magnetic field also has been realized.Compared with open-loop compensation,the PID closed-loop compensation reduces the average value of the residual magnetic field in the z-axis direction from 0.0244nT to-0.0023nT,and the mean-square error from 0.2083 nT to 0.0691 nT.In the same way,the average value of the residual magnetic field in the y-axis direction is reduced from 0.0816nT to-0.0042nT,and the mean-square error from 0.1316nT to 0.0461 nT.The magnitude of residual magnetic fields in both directions is decreased to the order of picotesla(pT).In addition,based on the signal waveforms of the magnetometer,a method of verifying the effect of magnetic compensation is proposed.展开更多
This paper presents the design,fabrication,and characterization of a novel high quality factor(Q)resonant pitch/roll gyroscope implemented in a 40μm(100)silicon-on-insulator(SOI)substrate without using the deep react...This paper presents the design,fabrication,and characterization of a novel high quality factor(Q)resonant pitch/roll gyroscope implemented in a 40μm(100)silicon-on-insulator(SOI)substrate without using the deep reactive-ion etching(DRIE)process.The featured silicon gyroscope has a mode-matched operating frequency of 200 kHz and is the first out-of-plane pitch/roll gyroscope with electrostatic quadrature tuning capability to fully compensate for fabrication non-idealities and variation in SOI thickness.The quadrature tuning is enabled by slanted electrodes with sub-micron capacitive gaps along the(111)plane created by an anisotropic wet etching.The quadrature cancellation enables a 20-fold improvement in the scale factor for a typical fabricated device.Noise measurement of quadrature-cancelled mode-matched devices shows an angle random walk(ARW)of 0.63°√h^(−1) and a bias instability of 37.7°h^(−1),partially limited by the noise of the interface electronics.The elimination of silicon DRIE in the anisotropically wet-etched gyroscope improves the gyroscope robustness against the process variation and reduces the fabrication costs.The use of a slanted electrode for quadrature tuning demonstrates an effective path to reach high-performance in future pitch and roll gyroscope designs for the implementation of single-chip high-precision inertial measurement units(IMUs).展开更多
Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced ...Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced noise by the sideband locking technique. Besides choosing an optimized modulation depth and different clockwise and counterclockwise modulation frequencies, the sideband is locked to the cavity resonance. With the proper modulation frequency, the carrier frequency component locates at a position far away from the resonant frequency, and then it is suppressed by the cavity itself, which can be taken as a bandpass filter. The amplitude of the carrier frequency can be suppressed by 20–25 d B additionally by the cavity and the total intensity suppression ratio can reach 115.74 d B. The backscattering induced noise can be eliminated for the adoption of different frequencies. The method can realize a stable and high suppression ratio without high requirements for parameter accuracy or device performance.展开更多
Nuclear magnetic resonance gyroscopes (NMRGs) are a kind of rotation-speed sensor that senses the angular velocity by measuring a frequency shift in the Larmor pre- cession of the nuclear spin in a constant magnetic...Nuclear magnetic resonance gyroscopes (NMRGs) are a kind of rotation-speed sensor that senses the angular velocity by measuring a frequency shift in the Larmor pre- cession of the nuclear spin in a constant magnetic field.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 60927005)the Innovation Foundation of BUAA for Ph. D. Graduates,Chinathe Fundamental Research Funds for the Central Universities,China (Grant No. YWF-10-01-A17)
文摘Dynamic characteristics of the resonant gyroscope are studied based on the Mathieu equation approximate solution in this paper.The Mathieu equation is used to analyze the parametric resonant characteristics and the approximate output of the resonant gyroscope.The method of small parameter perturbation is used to analyze the approximate solution of the Mathieu equation.The theoretical analysis and the numerical simulations show that the approximate solution of the Mathieu equation is close to the dynamic output characteristics of the resonant gyroscope.The experimental analysis shows that the theoretical curve and the experimental data processing results coincide perfectly,which means that the approximate solution of the Mathieu equation can present the dynamic output characteristic of the resonant gyroscope.The theoretical approach and the experimental results of the Mathieu equation approximate solution are obtained,which provides a reference for the robust design of the resonant gyroscope.
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2014AA123401)the National Key BasResearch and Development Program of China(Grant Nos.2016YFA0302103 and 2012CB821302)+1 种基金the National Natural Science Foundation of China(Gra11134003)Shanghai Excellent Academic Leaders Program of China(Grant No.12XD1402400)
文摘We theoretically investigate several parameters for the nuclear magnetic resonance gyroscope based on ^(133)C_(s–)^(129)Xe/^(131)Xe. For a cell containing a mixture of ^(133)Cs at saturated pressure, we investigate the optimal quenching gas(N_2) pressure and the corresponding pump laser intensity to achieve 30% ^(133)Cs polarization at the center of the cell when the static magnetic field B0 is 5 μT with different ^(129)Xe/^(131)Xe pressure. The effective field produced by spin-exchange polarized ^(129)Xe or ^(131)Xe sensed by ^(133)Cs can also be discussed in different^(129)Xe/^(131)Xe pressure conditions. Furthermore,the relationship between the detected signal and the probe laser frequency is researched. We obtain the optimum probe laser detuning from the D2(6~2S_(1/2)→ 6~2P_(3/2)) resonance with different ^(129)Xe/^(131)Xe pressure owing to the pressure broadening.
文摘Integrated optical gyroscopes(IOGs)have been an efficient tool for numerous applications in various fields,including inertial navigation,flight control,and earthquake monitoring.Here,we review the progress of integrated optical gyroscopes based on two categories of integrated interferometric optical gyroscopes(IIOGs)and integrated resonant optical gyroscopes(IROGs).
基金the Shanghai Aerospace Advanced Technology Joint Research Fund(No.USCAST2019-23)。
文摘Nuclear magnetic resonance gyroscope (NMRG) has the characteristics of high precision and miniaturization, and is one of the main applications of quantum technology in the field of navigation. The transverse relaxation time (T_(2)) of the xenon nuclear spin in the atomic cell of the NMRG directly affects the angular random walk of the gyro. Accurate and rapid measurement of T_(2) is conducive to further improvement of gyroscope. At present, for the measurement of T_(2), the schemes of two orthogonal lasers for pumping and detecting are usually used. By applying two fast-switching orthogonal static magnetic fields and a single beam of circularly polarized laser with corresponding wavelength to pump the atomic cell, the xenon nuclear macroscopic magnetic moment Larmor precession is generated. The cesium atoms parametric magnetometer in cell is formed to detect the free induction decay signal generated by nuclear spin precession of xenon atoms. The measurement of T_(2) by a single laser simplifies the measurement equipment compared with traditional method with two lasers. The experimental results show that the T_(2) of xenon atoms is more than 10 s, and the effects of temperature are studied, which lay the foundation for the subsequent improvement of gyro performance.
基金the Shanghai Aerospace Advanced Technology Joint Research Fund(No.USCAST2019-23)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(No.SL2021ZD202)。
文摘Based on the parametric resonance magnetometer(PRM)theory,this paper establishes an experimen-tal system of PRM.The experimental results are consistent with the theoretical predictions.A PRM has been developed with sensitivity of 0.5 pT/Hz^(1/2),which can detect the magnitude of residual magnetic field;furthermore,a proportion-integration-differentiation(PID)closed-loop magnetic compensation system of the residual magnetic field also has been realized.Compared with open-loop compensation,the PID closed-loop compensation reduces the average value of the residual magnetic field in the z-axis direction from 0.0244nT to-0.0023nT,and the mean-square error from 0.2083 nT to 0.0691 nT.In the same way,the average value of the residual magnetic field in the y-axis direction is reduced from 0.0816nT to-0.0042nT,and the mean-square error from 0.1316nT to 0.0461 nT.The magnitude of residual magnetic fields in both directions is decreased to the order of picotesla(pT).In addition,based on the signal waveforms of the magnetometer,a method of verifying the effect of magnetic compensation is proposed.
基金This work is supported by the DARPA MTO,Single-Chip Timing and Inertial Measurement Unit(TIMU)program under contract#N66001-11-C-4176.
文摘This paper presents the design,fabrication,and characterization of a novel high quality factor(Q)resonant pitch/roll gyroscope implemented in a 40μm(100)silicon-on-insulator(SOI)substrate without using the deep reactive-ion etching(DRIE)process.The featured silicon gyroscope has a mode-matched operating frequency of 200 kHz and is the first out-of-plane pitch/roll gyroscope with electrostatic quadrature tuning capability to fully compensate for fabrication non-idealities and variation in SOI thickness.The quadrature tuning is enabled by slanted electrodes with sub-micron capacitive gaps along the(111)plane created by an anisotropic wet etching.The quadrature cancellation enables a 20-fold improvement in the scale factor for a typical fabricated device.Noise measurement of quadrature-cancelled mode-matched devices shows an angle random walk(ARW)of 0.63°√h^(−1) and a bias instability of 37.7°h^(−1),partially limited by the noise of the interface electronics.The elimination of silicon DRIE in the anisotropically wet-etched gyroscope improves the gyroscope robustness against the process variation and reduces the fabrication costs.The use of a slanted electrode for quadrature tuning demonstrates an effective path to reach high-performance in future pitch and roll gyroscope designs for the implementation of single-chip high-precision inertial measurement units(IMUs).
文摘Polarization fluctuation induced noise and backscattering-induced noise are the dominant noises in resonant fiber optic gyroscopes. This Letter proposes a new method to suppress the carrier and backscattering induced noise by the sideband locking technique. Besides choosing an optimized modulation depth and different clockwise and counterclockwise modulation frequencies, the sideband is locked to the cavity resonance. With the proper modulation frequency, the carrier frequency component locates at a position far away from the resonant frequency, and then it is suppressed by the cavity itself, which can be taken as a bandpass filter. The amplitude of the carrier frequency can be suppressed by 20–25 d B additionally by the cavity and the total intensity suppression ratio can reach 115.74 d B. The backscattering induced noise can be eliminated for the adoption of different frequencies. The method can realize a stable and high suppression ratio without high requirements for parameter accuracy or device performance.
基金supported by the National Natural Science Foundation of China(Nos.61673041,61673041,and 61227902)the National High Technology Research and Development Program 863(No.2014AA123401)
文摘Nuclear magnetic resonance gyroscopes (NMRGs) are a kind of rotation-speed sensor that senses the angular velocity by measuring a frequency shift in the Larmor pre- cession of the nuclear spin in a constant magnetic field.