2024

• Record 169 of
  
  Title:Design and Imaging of Multi-frequency Interference System Based on T-lens Arrangement
  
  Author(s):Qiao, Yu(1,2); Chen, Guixiang(1,2); Zhai, Yusheng(1,2); Liu, Gang(3); He, Weiji(1,2); Chen, Qian(1,2)
  Source:Guangzi Xuebao/Acta Photonica Sinica
  Volume: 53  Issue: 7  DOI: 10.3788/gzxb20245307.0711002  Published: July 2024  
  Abstract:The angular resolution of conventional optical systems is limited by the size of the system aperture，and high resolution implies a larger system aperture. However，the increase of system aperture will make the volume，weight and power consumption of the whole system increase dramatically，which greatly increases the difficulty of engineering realization. Photonic integrated interferometric imaging technology is a new type of highly integrated detection technology that combines optical interferometric imaging principle and photonic integration technology，which utilizes a photonic integrated chip to replace the sensors in traditional imaging，significantly reducing the volume，weight，and power consumption of the imaging system. However，at present，this technology is still in the stage of theoretical and simulation calculation research，and the research of related experimental imaging system is relatively small，and the existing interferometric imaging system can only collect the spatial frequency of the target point by point. In order to investigate the effect of multi-frequency point sampling on photonic integrated interference technology，this paper proposes and builds a multi-frequency interference imaging system with T-shaped lens arrangement. The system selects laser as the illumination light source. The light from the laser is irradiated to the 2D grating after passing through the fiber collimator. The multi-level diffracted light through the grating is split into multiple paths and incident to the rear fiber collimator. The fiber collimator is used instead of a lens array. The lenses are divided into two groups，S group horizontally and R group vertically，and the T-distributed lens array allows for frequency acquisition of baselines in multiple directions and at different lengths. After the lens array through the optical switch to control the on-off optical path，optical switch on time signal through the optical fiber into the fiber coupler for interference. The detector is used to capture the interference signal and then the spatial frequency information of the target is solved，and the target image can be obtained by doing the inverse Fourier transform of the spectral map. We first simulate the imaging process of the system，the center wavelength of the illumination light source is set to 1 550 nm，the distance from the target to the light source is 1 m，and the orthogonal two-dimensional grating with the spatial frequencies of 80 lp/mm and 40 lp/mm in the transverse and longitudinal directions is selected as the target for the simulation，and the minimum sampling frequency of the system is 40 mm-1. In order to distinguish the target，a pair of black and white stripes of 80 lp/mm is at least 40 mm-1. In order to distinguish the target，a pair of black and white stripes of 80 lp/mm is at least 2 pixels，and the size of the received image is set to 576×576. In order to have a certain degree of redundancy，the size of the spectral image received by the lens is set to 1 152×1 152 in the simulation，corresponding to the highest frequency of 160 lp/mm，which can satisfy the demand for target detection. The actual imaging system is built under the same conditions as the simulation to image the target. After calculation，the Peak Signal to Noise Ratio（PSNR）of the simulated image is 30.79 dB，and the PSNR of the experimental reconstructed image is 27.95 dB，and the overall structure of the reconstructed image has not been changed，so the experiment successfully realizes the reconstruction of the target image. Of course，in the process of the experiment，we also found some problems in the system，such as the lack of spectrum acquisition，the influence of the external environment and other problems，to be further researched and solved. Overall，photon integrated interferometric imaging is a technology with practical value，and the design of the imaging system and the process of system imaging proposed in this paper provide guidance and direction for the practical engineering application of this technology. © 2024 Chinese Optical Society. All rights reserved.
  Accession Number: 20243116787788
• Record 170 of
  
  Title:Multi-wavelength and Transverse-mode-switchable Yb-doped Fiber Laser
  
  Author(s):Peng, Jianao(1,2); Chen, Wei(1,2); Hou, Chaoqi(3); Liu, Dandan(1,2); Pang, Fufei(1,2); Huang, Sujuan(1,2); Wang, Tingyun(1,2)
  Source:Guangzi Xuebao/Acta Photonica Sinica
  Volume: 53  Issue: 8  DOI: 10.3788/gzxb20245308.0814002  Published: August 2024  
  Abstract:Multi-wavelength lasers and transverse-mode-switchable lasers are expected to find applications in Wavelength Division Multiplexing （WDM） and Mode Division Multiplexing （MDM） systems. High-order transverse modes play a crucial role in the generation of cylindrical vector beams and vortex beams，making them suitable for applications such as micro-particle manipulation，quantum information，and laser material processing. While in solid-state lasers，specific transverse modes can be excited through phase and amplitude modulation，the entire laser system is relatively underdeveloped，with limited mode scalability. Therefore，the all-fiber structure of multi-wavelength and transverse-mode-switchable fiber lasers has sparked significant interest among scientists. Various technological approaches have been proposed to achieve multi-wavelength or transverse mode outputs from fiber lasers. However，there has been limited reporting on fiber lasers capable of simultaneously operating at multiple wavelengths while generating switchable transverse modes. Reported multi-wavelength and transverse mode-switchable fiber lasers often employ gain media consisting of traditional doped fibers，where the competitive advantage of the fundamental mode within the resonant cavity is significantly greater than that of higher-order modes. Consequently，these fiber lasers struggle to maintain stable and efficient output of higher-order modes. In this study，a Ring-Core Yb-Doped Fiber（RCYDF）was designed and fabricated. The unique structure of the ring-shaped doping region aligns well with the dual-peak spatial electromagnetic field distribution of the LP11 mode，prioritizing the gain acquisition for the LP11 mode within the gain fiber. This design facilitates stable oscillation and efficient output of the LP11 mode laser. Few-Mode Fiber Bragg Gratings（FMFBGs）serve not only as ideal wavelength-selective elements but also as components for achieving transverse mode switching. Utilizing a pair of FMFBGs as the laser resonant cavity and the fabricated RCYDF as the laser gain medium，a multi-wavelength and transverse-mode-switchable fiber laser was demonstrated. By simply adjusting the polarization controller placed on the RCYDF，stable laser oscillation at both single and dual wavelengths can be achieved. When operating in a single-wavelength state，two transverse modes，namely LP01 and LP11 modes，can be switched. The 3 dB linewidths for both modes are less than 0.08 nm，with a Side-Mode Suppression Ratio（SMSR）of 52.2 dB for LP01 mode and 46.5 dB for LP11 mode. The output spectra were monitored every 10 minutes over a total duration of 60 minutes. Fluctuations in the central wavelength and optical intensity of the two laser modes were observed to be 0.01 nm and 1 dB，respectively. No significant changes were observed in the spectral shape. Furthermore，the laser thresholds for LP01 and LP11 modes are 372.51 mW，and 482.51 mW，respectively，with corresponding slope efficiencies of 34.34% and 49.09%. The higher slope efficiency of the LP11 mode is attributed to the enhanced LP11 mode resonance capability of the custom-designed RCYDF compared to traditional Yb-doped fibers，making it highly valuable for applications in fiber lasers targeting higher-order mode outputs. The proposed dual-wavelength and transverse-mode-switchable fiber laser offers advantages of simplicity，ease of control，and stable operation，presenting promising applications in MDM system and laser material processing. © 2024 Chinese Optical Society. All rights reserved.
  Accession Number: 20243917112602
• Record 171 of
  
  Title:Alternating projection combined with fast gradient projection (FGP-AP) method for intensity-only measurement optical diffraction tomography in LED array microscopy
  
  Author(s):Yang, Zewen(1); Zhang, Lu(1,2); Liu, Tong(1); Wang, Huijun(1); Tang, Zhiyuan(3); Zhao, Hong(1,2); Yuan, Li(4); Zhang, Zhenxi(5); Liu, Xiaolong(6)
  Source:Biomedical Optics Express
  Volume: 15  Issue: 4  DOI: 10.1364/BOE.518955  Published: April 1, 2024  
  Abstract:Optical diffraction tomography (ODT) is a powerful label-free measurement tool that can quantitatively image the three-dimensional (3D) refractive index (RI) distribution of samples. However, the inherent "missing cone problem,"limited illumination angles, and dependence on intensity-only measurements in a simplified imaging setup can all lead to insufficient information mapping in the Fourier domain, affecting 3D reconstruction results. In this paper, we propose the alternating projection combined with the fast gradient projection (FGP-AP) method to compensate for the above problem, which effectively reconstructs the 3D RI distribution of samples using intensity-only images captured from LED array microscopy. The FGP-AP method employs the alternating projection (AP) algorithm for gradient descent and the fast gradient projection (FGP) algorithm for regularization constraints. This approach is equivalent to incorporating prior knowledge of sample non-negativity and smoothness into the 3D reconstruction process. Simulations demonstrate that the FGP-AP method improves reconstruction quality compared to the original AP method, particularly in the presence of noise. Experimental results, obtained from mouse kidney cells and label-free blood cells, further affirm the superior 3D imaging efficacy of the FGP-AP method. © 2024 Optica Publishing Group.
  Accession Number: 20241815995654
• Record 172 of
  
  Title:Redundant-Coded Masked Grid Pattern for Full-Sky Star Identification
  
  Author(s):Liao, Jiawen(1); Wei, Xin(2); Niu, Axi(3); Zhang, Yanning(3); Kweon, In So(4); Qi, Chun(5)
  Source:IEEE Transactions on Aerospace and Electronic Systems
  Volume: 60  Issue: 4  DOI: 10.1109/TAES.2024.3374714  Published: 2024  
  Abstract:Full-sky autonomous star identification is one of the key technologies in the research on star sensors. As one of the classical pattern-based star identification methods, the grid algorithm has shown promising performance. Na further modified it to improve its robustness to position noise. However, the inherent alignment star mismatch and pattern inconsistency are still not solved. To address these problems, we propose a novel star identification method. Specifically, we design distance-guided redundant-coded patterns for different alignment stars to alleviate the problem of alignment star mismatch. Then, we create a masked grid pattern to address the inconsistency between the sensor pattern and the catalog pattern. The distances of the reference stars to their corresponding alignment stars are adopted to assist in choosing the correct alignment star, as well as reducing the number of catalog patterns that need to be evaluated. Experimental results on both synthesized and night sky images show that the proposed algorithm is quite robust to false stars, position noise, and magnitude noise. The identification accuracy of this algorithm is 98.43% with standard deviations of position noise is 2.0 pixels and 98.52% with standard deviations of magnitude noise is 0.5 Mv. Moreover, the algorithm obtains an average identification accuracy of 99.6% from night sky images. © 1965-2011 IEEE.
  Accession Number: 20241215762514
• Record 173 of
  
  Title:X-ray compressed ultrafast photography under the constraint of time-integrated-image for X-pinch
  
  Author(s):Zhou, Haoyu(1,2); Yao, Zhiming(2); Sheng, Liang(2); Song, Yan(2); Liu, Zhen(2); Han, Changcai(2); Zhu, Zijian(2); Li, Yang(2); Duan, Baojun(2); Ji, Chao(3); Wu, Jian(4); Hei, Dongwei(2); Liu, Yinong(1)
  Source:Optics and Lasers in Engineering
  Volume: 183  Issue:   DOI: 10.1016/j.optlaseng.2024.108508  Published: December 2024  
  Abstract:This paper presents a time-integrated-image-constrained X-ray compressed ultrafast photography system for comprehensive measurement of the aluminum X-pinch evolution process. The system incorporates a pinhole and a scintillator to convert the X-ray video to fluorescence video. The fluorescence video is recorded by a compressed ultrafast photography channel and a time-integrated imaging channel respectively. By recording the fluorescence video instead of the self-emission visible light video, the long tailing effect can be significantly inhibited, which is more conducive to the image reconstruction of the compressed ultrafast photography channel. In addition, by combining the time-integrated imaging channel, the reconstruction quality is significantly improved. Based on the "Qin-I" pulsed power facility, we recorded the continuous two-dimensional X-ray evolution process of aluminum X-pinch for the first time. Our results contribute to deep insights into the temporal-spatial distribution of the X-pinch imploding plasma. It can also offer direction for the assessing of X-ray backlight photography applications at the X-pinch facility. © 2024 Elsevier Ltd
  Accession Number: 20243416890078
• Record 174 of
  
  Title:Simulation Analysis of Key Parameters for CH4 Gas Point Source Detection Based on F-P Interferometer
  
  Author(s):Zhang, Qiang(1,2); Bai, Caixun(3); Fu, Di(1); Li, Juan(2); Chang, Chenguang(1); Zhao, Hengxiang(1); Wang, Sufeng(1); Feng, Yutao(1)
  Source:Guangzi Xuebao/Acta Photonica Sinica
  Volume: 53  Issue: 1  DOI: 10.3788/gzxb20245301.0130001  Published: January 2024  
  Abstract:The increase in greenhouse gases carbon dioxide and methane can directly lead to changes in the global climate and cause a significant impact on the economies of countries and human life. Methane，as the second-largest greenhouse gas on Earth，has a global warming potential 30 times higher than CO2 over a 100-year period，and its lifespan is approximately 9.1 years. At present，anthropogenic CH4 emissions primarily originate from numerous point sources. Implementing measures to reduce CH4 emissions can help decrease the rate of global warming. Therefore，it is crucial to conduct research on monitoring technologies for CH4 and investigate key carbon emission sources. Hyperspectral satellite remote sensing for detecting greenhouse gases has become a candidate technology for point source detection. It has advantages such as high viewpoint，wide field of view，the ability to achieve dynamic monitoring，obtain more precise and demand-driven information data. Utilizing remote sensing methods to monitor and provide feedback on point source emissions of greenhouse gases like methane plays a crucial role in effectively addressing climate change. Existing payload technologies in China are geared towards large satellite platforms，enabling wide-area coverage with low spatial resolution monitoring. However，traditional methods such as grating spectrometry，Michelson interferometry，and spatial heterodyne are unable to meet the efficient and high-precision monitoring requirements for small-scale anthropogenic emission sources. They struggle to achieve point source detection. Therefore，it is necessary to conduct research on satellite remote sensing carbon monitoring technologies that offer high accuracy and high spatial resolution. The Fabry-Pérot interferometry technique possesses extremely high spectral resolution，capable of discerning minute wavelength differences in the spectrum. The theoretical basis of this technique is the multi-beam equal-inclination interferometry. By using an interference ring，it is possible to directly obtain the spectral information of target light at different incident angles. By collecting the spectral information corresponding to different wavelengths of the target at different positions from multiple consecutive shots，the target spectral curve is obtained. This technique establishes a relationship between CH4 gas concentration and the depth of spectral curve notches，offering advantages in point source detection with high spectral resolution and high spatial resolution. In CH4 gas detection，the parameters of the Fabry-Pérot interferometer and the optical filter have a significant impact on detection sensitivity. Properly configuring these parameters is crucial for improving detection accuracy. This paper presents a study on a high spatial resolution method for detecting point sources of methane gas based on the principle of multi-beam interferometric spectral imaging. Firstly，the working principle and detection scheme of the methane gas detector are introduced. The system parameters of the Fabry-Pérot interferometer are designed， and a forward model for methane gas detection is established. Subsequently，the correspondence between interference signals and methane concentration，as well as the influence of instrument parameters on detection sensitivity，are analyzed. In the end，iterative optimization is performed to obtain the optimal values of various optical structural parameters. The results indicate that within the methane detection wavelength range of 1 630~1 675 nm，with a free spectral range of 12.5 nm and a spectral resolution of 0.1 nm，the optimal parameters for the Fabry-Pérot interferometer are a cavity length of 0.08 mm and an intra-cavity reflectance of 97.5%. By using a cutoff filter with a range of（1 630±4）nm ~ （1 675±4）nm，the relative change in interference signal corresponding to a 25% concentration variation of the detection source falls within the range of［0.65%，4.30%］，indicating a good detection sensitivity. The research results of this study provide a theoretical basis and technical support for high-precision. © 2024 Chinese Optical Society. All rights reserved.
  Accession Number: 20240815582116
• Record 175 of
  
  Title:Research on the spacecraft ground equivalence test assessment problem: A comprehensive assessment method combining interval-type evaluation and prospect-two-dimensional cloud
  
  Author(s):Ding, Wenzhe(1,2,3); Bai, Xiang(1); Wang, Qingwei(1); Yao, Huisheng(1); Liu, Jian(1); Yang, Hong(1,4)
  Source:Applied Soft Computing
  Volume: 166  Issue:   DOI: 10.1016/j.asoc.2024.111882  Published: November 2024  
  Abstract:For the complex dual-attribute qualitative assessment problem of spacecraft ground equivalence tests, the paper proposes a comprehensive assessment method that integrates interval-type evaluation with prospect theory and the two-dimensional cloud model. Firstly, to reduce the difficulty of determining indicator weights, the paper adopts interval-type evaluation and obtains reasonable interval weights of each indicator under dual attributes by interval analytic hierarchy process (IAHP). Secondly, to reduce the uncertainty of assessment and achieve the transformation of interval weights to value weights, the paper combines the prospect theory to obtain the value weight of each indicator that can maximize the personality preference satisfaction of the decision-maker by maximizing the integrated prospect value. During this period, to avoid the construction of a complex score function, the theoretical gain and loss values of indicator evaluation were obtained directly from the theoretical calculation based on the location of interval evaluation results in relation to interval psychological reference points. Again, to judge the validity of the interval evaluation of indicators, the paper theoretically derives an inverse cloud generator for interval-type samples and then realizes the validity analysis of the interval evaluation of indicators based on the 3-sigma principle of clouds. Then, to solve the problem of dual-attribute assessment of equivalence tests, the paper achieves the effective assessment of spacecraft ground equivalence tests through inter-cloud aggregation and similarity calculation of two-dimensional cloud models. Finally, the application of the method in a specific assessment case verifies the feasibility, validity, and practicality of the method in this paper. © 2024 Elsevier B.V.
  Accession Number: 20243817061887
• Record 176 of
  
  Title:Domain Adaptation of Anchor-Free object detection for urban traffic
  
  Author(s):Yu, Xiaoyong(1,2); Lu, Xiaoqiang(3)
  Source:Neurocomputing
  Volume: 582  Issue:   DOI: 10.1016/j.neucom.2024.127477  Published: May 14, 2024  
  Abstract:Modern detectors are mostly trained under single and limited conditions. However, object detection faces various complex and open situations in autonomous driving, especially in urban street scenes with dense objects and complex backgrounds. Due to the shift in data distribution, modern detectors cannot perform well in actual urban environments. Using domain adaptation to improve detection performance is one of the key methods to extend object detection from limited situations to open situations. To this end, this article proposes a Domain Adaptation of Anchor-Free object detection (DAAF) for urban traffic. DAAF is a cross-domain object detection method that performs feature alignment including two aspects. On the one hand, we designed a fully convolutional adversarial training method for global feature alignment at the image level. Meanwhile, images can generally be decomposed into structural information and texture information. In urban street scenes, the structural information of images is generally similar. The main difference between the source domain and the target domain is texture information. Therefore, during global feature alignment, this paper proposes a method called texture information limitation (TIL). On the other hand, in order to solve the problem of variable aspect ratios of objects in urban street scenes, this article uses an anchor-free detector as the baseline detector. Since the anchor-free object detector can obtain neither explicit nor implicit instance-level features, we adopt Pixel-Level Adaptation (PLA) to align local features instead of instance-level alignment for local features. The size of the object has the greatest impact on the final detection effect, and the object scale in urban scenes is relatively rich. Guided by the differentiation of attention mechanisms, a multi-level adversarial network is designed to perform feature alignment of the output space at different feature levels called Scale Information Limitation (SIL). We conducted cross-domain detection experiments by using various urban streetscape autonomous driving object detection datasets, including adverse weather conditions, synthetic data to real data, and cross-camera adaptation. The experimental results indicate that the method proposed in this article is effective. © 2024 Elsevier B.V.
  Accession Number: 20241215767931
• Record 177 of
  
  Title:Domino-like water film manipulation with multifunctionality
  
  Author(s):Yang, Pengyu(1); Yin, Kai(1,2,3); Li, Xun(4); Song, Xinghao(1); Wang, Lingxiao(1); Pei, Jiaqing(1); Wu, Tingni(1); Huang, Yin(1); Awan, Saif U.(5); Khalil, Ahmed S. G.(6)
  Source:Applied Physics Letters
  Volume: 125  Issue: 5  DOI: 10.1063/5.0225775  Published: July 29, 2024  
  Abstract:Domino effect is widely known and intuitively understood. Although the concept is frequently used, a few works combine it with liquid manipulation. Liquid manipulation is essential in many fields; however, large-scale liquid manipulation using minimal forces is still a challenge. Here, we show a domino-like liquid manipulation process triggered by wind on heterogeneously wettable surfaces. This effect was demonstrated using velocities of wind between 2.2 and 3.0 m/s on structured surfaces containing water film thickness in the range of 2.5-4.5 mm. The domino dewetting surfaces were shown on various patterned designs with 32-224 mm in length; however, under ideal conditions, the effect could be infinitely transmissible. Such a concept might apply to long-distance directional transportation of floats, and bed bottom dust cleaning. Other designs, such as a branched tree structure, can drive larger objects, and remote circuit interrupters were shown. This method provides an approach for manipulation of water movement by tiny forces triggered toward multifunctionality. © 2024 Author(s).
  Accession Number: 20243216825437
• Record 178 of
  
  Title:Flexible fiberbotic laser scalpels: Material and fabrication challenges
  
  Author(s):Zou, Yuqi(1,2); Ren, Zhihe(1,2); Xiang, Yuanzhuo(1,2); Liu, Chao(1,2); Gao, Anzhu(3,4); Huang, Shaoping(4); Yang, Lvyun(1); Hou, Chong(5); Guo, Haitao(6); Yang, Guang-Zhong(4); Tao, Guangming(1,2,4)
  Source:Matter
  Volume: 7  Issue: 3  DOI: 10.1016/j.matt.2024.01.007  Published: March 6, 2024  
  Abstract:Rapidly developed fiber lasers have shown great potential in interventional urology, inspiring the use of advanced laser delivery to meet the demand for manipulation in other complex surgical scenarios. While medical robots are enhancing precision in the field of minimally invasive surgery, laser ablation has been demonstrated as a promising candidate compared to traditional mechanical cutting tools in interventions. Nevertheless, based on their ablation mechanisms, the advantages of lasers are still not fully leveraged. In this Perspective, we outline how fiber-shaped robots combined with laser scalpels are primed to emerge as the next generation of medical robots to achieve minimally invasive surgery. We review the mechanisms involved, analyze their applications, and discuss several prospects for future applications. © 2024 Elsevier Inc.
  Accession Number: 20240915657499
• Record 179 of
  
  Title:On-line measurement of COD and nitrate in water against stochastic background interference based on ultraviolet–visible spectroscopy and physics-informed multi-task learning
  
  Author(s):Liu, Jiacheng(1,2,3); Yu, Tao(1); Wang, Xueji(1); Liu, Xiao(1); Wu, Lichao(4); Liu, Hong(1); Zhao, Yubo(1,2); Zhou, Guangya(3); Yu, Weixing(1); Hu, Bingliang(1)
  Source:Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
  Volume: 323  Issue:   DOI: 10.1016/j.saa.2024.124857  Published: December 15, 2024  
  Abstract:Traditional ultraviolet–visible spectroscopic quantitative analytical methods face challenges in simultaneous and long-term accurate measurement of chemical oxygen demand (COD) and nitrate due to spectral overlap and the interference from stochastic background caused by turbidity and chromaticity in water. Addressing these limitations, a compact dual optical path spectrum detection sensor is introduced, and a novel ultraviolet–visible spectroscopic quantitative analysis model based on physics-informed multi-task learning (PI-MTL) is designed. Incorporating a physics-informed block, the PI-MTL model integrates pre-existing physical knowledge for enhanced feature extraction specific to each task. A multi-task loss wrapper strategy is also employed, facilitating comprehensive loss evaluation and adaptation to stochastic backgrounds. This novel approach significantly outperforms conventional models in COD and nitrate measurement under stochastic background interference, achieving impressive prediction R2 values of 0.941 for COD and 0.9575 for nitrate, while reducing root mean squared error (RMSE) by 60.89 % for COD and 77.3 % for nitrate in comparison to the conventional chemometric model partial least squares regression (PLSR), and by 30.59 % and 65.96 %, respectively, in comparison to a benchmark convolutional neural network (CNN) model. The promising results emphasize its potential as a spectroscopic instrument designed for online multi-parameter water quality monitoring against stochastic background interference, enabling long-term accurate measurement of COD and nitrate levels. © 2024
  Accession Number: 20243016765881
• Record 180 of
  
  Title:Adaptive Kalman Filter Based on Online ARW Estimation for Compensating Low-Frequency Error of MHD ARS
  
  Author(s):Su, Yunhao(1,2); Han, Junfeng(1); Ma, Caiwen(1); Wu, Jianming(3); Wang, Xuan(1); Zhu, Qinghua(3); Shen, Jie(3)
  Source:IEEE Transactions on Instrumentation and Measurement
  Volume: 73  Issue:   DOI: 10.1109/TIM.2024.3375962  Published: 2024  
  Abstract:Magnetohydrodynamic angular rate sensor (MHD ARS) can precisely detect angular vibration information with a bandwidth of up to one kilohertz. However, due to secondary flow and viscous force, it experiences performance degradation when measuring low-frequency angular vibrations. This article presents an adaptive Kalman filter that uses online angular random walk (ARW) estimation to correct for the low-frequency error of MHD ARS, where a microelectromechanical system (MEMS) gyroscope is used to measure low-frequency vibrations. The proposed algorithm determines the signal frequency based on the ARW coefficients and adjusts the measurement noise covariance to achieve accurate fusion results. Thus, the method solves the problem of frequency-dependent variation of the amplitude response of the sensors in data fusion. Initially, the algorithm calculates the ARW coefficient recursively utilizing the measurement signals of both sensors. Then, the operational frequencies of both sensors are determined by analyzing the correlation between the ARW coefficient and frequency. Subsequently, in the Sage-Husa adaptive Kalman filter (SHAKF), the Kalman gain matrix is adjusted by modifying the measurement noise variances of both sensor signals individually. Moreover, the stability of the proposed algorithm is achieved by introducing an adaptive matrix to constrain the measurement noise covariance estimation. In the experiment, the fusion effects of single-frequency and mixed-frequency signals are tested separately. The experimental results show that for frequency variation and frequency mixing, the proposed algorithm in this study significantly improves the fusion results. © 1963-2012 IEEE.
  Accession Number: 20241515880340