Table of Content

    28 November 2022, Volume 56 Issue 11 Previous Issue    Next Issue
    Guidance, Navigation and Control
    Linear Parameter-Varying Integrated Control Law Design for a Hypersonic Vehicle
    YANG Shu, QIAN Yunxiao, YANG Ting
    2022, 56 (11):  1427-1437.  doi: 10.16183/j.cnki.jsjtu.2022.190
    Abstract ( 851 )   HTML ( 352 )   PDF (2903KB) ( 564 )   Save

    A linear parameter-varying (LPV) integrated control law is designed for a hypersonic vehicle to achieve trajectory control based on an altitude-horizontal trajectory control concept. The LPV output-feedback control theory and pole placement techniques are employed to design parameters of the control law within a Mach number envelope. Such a control law performs integrated control for longitudinal and lateral-directional dynamics of the vehicle, free from the scheme of inner and outer control loops of classical flight controls and ensuring robust and optimal control performance in the sense of L2-induced norm. A mathematical model of the hypersonic vehicle is developed in the Earth-centered-Earth-fixed reference frame. Earth rotation, Earth oblateness, and the second order harmonic perturbations of Earth are considered in the model. Numerical simulations are conducted to examine the performance of the LPV controller. The simulation results indicate that the closed-loop system of the hypersonic vehicle achieves D-stability. The LPV control law achieves a good performance in vehicle trajectory control and has sufficient robustness with respect to perturbations and sensor noise.

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    Cooperative Navigation of UAV Formation Based on Relative Velocity and Position Assistance
    GUO Pengjun, ZHANG Rui, GAO Guangen, XU Bin
    2022, 56 (11):  1438-1446.  doi: 10.16183/j.cnki.jsjtu.2022.232
    Abstract ( 757 )   HTML ( 26 )   PDF (1260KB) ( 445 )   Save

    Because the navigation errors of inertial navigation system accumulate with time, the unmanned aerial vehicle (UAV) formation that only relies on inertial navigation system for positioning cannot obtain precision navigation information in long time flight. To solve this problem, this paper proposes a cooperative navigation scheme for master-slave UAV formation. First, the UAV is equipped with relative navigation sensors to measure the relative velocity and position information between the members of the master-slave UAV formation. Then, considering the relative pose of formation members, the spatial unified transformation scheme is studied. The absolute navigation information measured by each member of UAV formation by inertial navigation system and the relative navigation information measured by relative sensors is unified into the same navigation coordinate system. Finally, a cooperative navigation scheme based on relative velocity and relative position assistance is given. The 30 min simulation results show that the speed and position errors of each cluster converge to 0.1 m/s and 5 m respectively under this scheme, which is more suitable than the inertial navigation system.

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    In-Flight Alignment Method of Integrated SINS/GPS Navigation System Based on Combined PF-UKF Filter
    GAO Honglian, YOU Jie, CAO Songyin
    2022, 56 (11):  1447-1452.  doi: 10.16183/j.cnki.jsjtu.2022.167
    Abstract ( 554 )   HTML ( 13 )   PDF (1969KB) ( 348 )   Save

    Aimed at the modeling error of the integrated strapdown inertial navigation system(SINS)/global positioning system (GPS) navigation system and the particle degradation problem of particle filter(PF), an in-flight alignment method of integrated SINS/GPS navigation system based on the combined PF-UKF filter is proposed, in combiation with the unscented Kalman filter(UKF). First, the attitude angle is replaced by the error quaternion. The position and velocity differences between SINS and GPS are selected as the observation variables. In addition, a novel error equation of the integrated navigation system is established. Moreover, the sampled particles are divided into random particles and deterministic particles in the proposed combined PF-UKF filter. The random particles are collected by probability density function, and the determined particles are the state values obtained by collecting sigma point of UKF algorithm. Therefore, the proposed method can effectively reduce the complexity of PF and the degree of particle degradation. The simulation results show that compared with the UKF algorithm, the proposed method can effectively improve the error accuracy of integrated navigation system with a better robustness.

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    Control of Unmanned Aerial Vehicle Based on Gain Adaptive Super-Twisting Sliding Mode Theory
    ZHOU Qixian, WANG Yin, SUN Xuean
    2022, 56 (11):  1453-1460.  doi: 10.16183/j.cnki.jsjtu.2022.238
    Abstract ( 721 )   HTML ( 13 )   PDF (1184KB) ( 375 )   Save

    In this paper, a nonlinear control method is proposed based on the framework of gain adaptive sliding mode control to deal with the attitude control problem of an unmanned aerial vehicle (UAV), which shows a strong robustness with respect to dynamical uncertainties and external disturbance. In the proposed method, an adaptive gain schedule scheme is proposed to deal with dynamical uncertainties while suppressing the chattering in the sliding mode control. First, the UAV model is introduced and its mathematical model is given. Then, the error is used as the state variable to design a stably converging sliding mode surface, and the gain adaptive super-twisting sliding mode (ASTSM) algorithm is used to design a UAV attitude controller that can converge in finite time, and the stability of the closed-loop UAV system is demonstrated by the Lyapunov’s second method. Finally, the efficiency of the proposed method is demonstrated through comparative simulations.

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    A Sliding Window Adaptive Filtering Algorithm for Autonomous Navigation of the Approach Phase of Deep Space Probe
    ZHANG Wenjia, MA Xin
    2022, 56 (11):  1461-1469.  doi: 10.16183/j.cnki.jsjtu.2022.233
    Abstract ( 580 )   HTML ( 6 )   PDF (2984KB) ( 354 )   Save

    When the deep space probe approaches the target planet, due to the rapid increase of the gravity of the target planet, the orbital dynamics model will have a rapid acceleration change. Because the noise covariance is not completely known, the traditional filtering algorithm cannot obtain the optimal estimation of navigation parameters, which is difficult to meet the performance requirements of the approach navigation system. In order to meet the requirements of high stability and accuracy of the system, a sliding window adaptive nonlinear filtering algorithm based on system noise covariance is proposed. By constructing the system noise covariance update function and using the sliding window to smooth the noise covariance, the errors caused by velocity noise and position noise are separated, the filter parameter information used is updated in real time, and the system noise covariance is adjusted adaptively. Taking the Mars probe as an example, the simulation results show that, compared with the traditional unscented Kalman filtering method, the position accuracy and velocity accuracy of the proposed method are improved by 90.97% and 66.17% respectively, which suppresses the rapidly changing integral error on the system model, and solves the divergence problem of the traditional filtering method. In addition, the influence of filtering period and window size on navigation performance is analyzed, which provides a feasible new adaptive filtering method for autonomous navigation of deep space exploration.

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    Analysis of Entry Footprint Based on Pseudospectral Method
    LI Zhaoting, ZHOU Xiang, ZHANG Hongbo, TANG Guojian
    2022, 56 (11):  1470-1478.  doi: 10.16183/j.cnki.jsjtu.2022.256
    Abstract ( 606 )   HTML ( 4 )   PDF (1383KB) ( 360 )   Save

    Entry footprint is an essential manifestation of vehicle maneuverability, which can provide the basis for trajectory planning and guidance, landing point selection, etc. A fast footprint-generation method based on the pseudospectral method is proposed. The influencing factors of footprint are simulated and analyzed. In this method, the attack and bank angles are simultaneously discretized as control quantities to form the nonlinear programming problem of the pseudospectral method, and the footprint is obtained by solving the maximum transverse range problem for several different longitudinal conditions. Moreover, the affecting factors of the footprint are studied. The simulation results show that the mass, reference area, atmospheric density, etc., do not cause the change of the footprint within a specific range. Beyond a certain range, the short longitudinal trajectory would be significantly affected. The left half of the footprint is affected, while the right half is not changed. The effect of the lift-to-resistance ratio on the footprint is significant, and its size is positively related to the footprint range.

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    Unmanned Aerial Vehicle Situation Assessment Based on Cumulative Prospect Theory and Three-Way Decision
    LI Weiwei, GAO Peixue, CHEN Jin, LU Yuqing
    2022, 56 (11):  1479-1490.  doi: 10.16183/j.cnki.jsjtu.2021.400
    Abstract ( 556 )   HTML ( 12 )   PDF (1395KB) ( 427 )   Save

    General uninhabited aerial vehicle (UAV) situation assessment methods do not consider the influence of complex external environment on the decision-maker, and usually only get the ranking results of the evaluation. Since the decision-maker needs to make decisions in a short period of time, misjudgments or missing strike windows often occur. To address this problem, a three-way decision model based on the cumulative prospect theory is proposed. First, the method the utilizes intuitionistic fuzzy technique for order preference by similarity to an ideal solution to estimate the conditional probability of each target and obtains the situation assessment result. Next, the method calculates the intuitionistic fuzzy situation information obtained by the UAV based on the cumulative prospect theory, and obtains the corresponding cumulative prospect value when each target performs different actions. Finally, based on the principle of maximizing the cumulative prospect value, a new three-way decision rule is derived to divide the situational assessment results into three regions. The experimental analysis shows that the method not only obtains the target threat ranking, but also classifies the target threat level objectively. At the same time, it considers the psychology of the decision-maker in the assessment process, and obtains the target threat assessment results that meet the traits of the decision-maker, providing a reasonable decision support for the complex and changing air combat.

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    Linear Matrix Inequality Based Stability Analysis of Linear/Nonlinear Switching Active Disturbance Rejection Control System
    WAN Hui, QI Xiaohui, LI Jie
    2022, 56 (11):  1491-1501.  doi: 10.16183/j.cnki.jsjtu.2021.203
    Abstract ( 512 )   HTML ( 8 )   PDF (1537KB) ( 412 )   Save

    A decoupling controller based on linear/nonlinear switching active disturbance rejection control (SADRC) is designed for a class of continuous linear nominal multi-input multi-output (MIMO) system. The system model is introduced and a linear matrix inequality (LMI) based absolute stability analysis approach is proposed for the designed SADRC decoupling controller. Finally, the effectiveness of the proposed method is verified by numerical simulations.

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    Biomedical Engineering
    Transcutaneous Wireless Energy Transmission of Biaxial Actuated Artificial Anal Sphincter
    HUA Fangfang, YAN Guozheng, WANG Lichao, CHAI Chuanye, XIAO Dunxi
    2022, 56 (11):  1502-1508.  doi: 10.16183/j.cnki.jsjtu.2021.216
    Abstract ( 513 )   HTML ( 6 )   PDF (3519KB) ( 270 )   Save

    As an implantable medical device, the transcutaneous wireless energy transmission (TET) system of biaxial actuated artificial anal sphincter (BAAS) after implantation in vivo is affected by the hyperplasia of the parcel. The coupling performance is obviously lower than that of in vitro experiments, which reduces the practical value in medical treatment. Based on the experimental results of the TET system of BAAS, mainly aimed at the problem of transmission angle caused by the hyperplasia of the parcel, the existing TET system is analyzed and studied, and the relation curve between transmission angle and transmission efficiency are obtained. The experimental results show that when the transmission distance is 30 mm, the transmission efficiency reaches more than 60%. When the transmission distance is 30 mm and the transmission angle is 20°, the average transmission efficiency of the experiment can reach 66.65%. When the transmission angle is 30°, the average transmission efficiency of the experiment can reach 59.96%. The maximum of charging temperature of the transmitting coil is 23 ℃, which will not cause low temperature scald to the human body. It can meet the performance requirements of the BAAS system and achieve the purpose of long distance and high efficiency transmission.

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    Design of Mandibular Angle Osteotomy Plane Based on Point Cloud Semantic Segmentation Algorithm
    LÜ Chaofan, YAN Yingjie, LIN Li, CHAI Gang, BAO Jinsong
    2022, 56 (11):  1509-1517.  doi: 10.16183/j.cnki.jsjtu.2021.103
    Abstract ( 491 )   HTML ( 8 )   PDF (7077KB) ( 364 )   Save

    Mandibular angle osteotomy is a popular craniofacial plastic surgery in recent years. Usually, preoperative planning of mandibular angle osteotomy is completed by an experienced doctor, which is cumbersome and time-consuming. In order to improve the efficiency of osteotomy planning, a design method of mandibular angle osteotomy plane based on point cloud semantic segmentation network is proposed. After three-dimensional reconstruction of the skull computer tomography (CT) scan data, the three-dimensional model of the mandible is converted into point cloud data through uniform sampling. The resection area of the mandible is predicted by the proposed algorithm, which is used to calculate the mandibular angle osteotomy plane. The proposed semantic segmentation network mainly includes 2 parts: a local feature extraction layer based on the attention mechanism, which is used to extract fine-grained local structure information, and a non-local feature extraction layer based on Transformer, which is used to extract the global context information of the point cloud. On the constructed mandible semantic segmentation data set, the proposed algorithm is compared with other point cloud semantic segmentation algorithms. The results show that the proposed algorithm can achieve the best prediction of the mandibular angle resection area, which is better than current common point cloud semantic segmentation algorithms.

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    “Window Effect” and Protective Measures of Exogenous Pulsed Electromagnetic Field on Implantable Cardiac Pacemaker
    LU Wu, DING Ranran, ZHAO Wenbin, HUANG Dong, WANG Zheming
    2022, 56 (11):  1518-1531.  doi: 10.16183/j.cnki.jsjtu.2021.326
    Abstract ( 757 )   HTML ( 6 )   PDF (24935KB) ( 510 )   Save

    The electromagnetic interference (EMI) from pulsed electromagnetic field (PEMF) on pacemakers is unignorable in modern power grids and healthcare environments, but there is limited study on the interaction mechanisms and protective measures. In this paper, an in-vitro human chest model for pacemaker implantation is made by using pork tissues immersed in 0.9% sodium chloride solution. The effect of PEMFs generated by the switching actions of common electrical equipment and low-frequency medical equipment on pacemakers is simulated by using fast-front current sources. The pulse forming line theory is employed for analyzing the waveform compression of PEMFs in human thoracic cavity. Further, the parameterized bio-electromagnetic transient model of pacemaker in combination with biological tissues is established in finite element software. The results show that pacemaker malfunctions including pacing inhibition and P pulmonale occur under PEMF. The “Window effect” in subcutaneous pouch under PEMF is found by changing the winding of pacemaker leads in the pouch. Based on the research finding, a protective strategy by using composite materials to shield the window area is proposed. The theoretical feasibility of this protective measure is confirmed by simulation, where the intensity of pacemaker EMI could be reduced by 80 dB when the composite materials shielding is used. Finally, a safe distance is developed for pacemaker wearers in electrical and medical environments.

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    Characteristics of Droplet Transmission in Buses in Different Air Supply Modes
    CHEN Zhixin, WANG Yiping, YANG Yafeng, SU Jianjun, YANG Bin
    2022, 56 (11):  1532-1540.  doi: 10.16183/j.cnki.jsjtu.2021.318
    Abstract ( 460 )   HTML ( 8 )   PDF (32872KB) ( 487 )   Save

    In order to study the spread characteristics of virus droplets in the bus and predict the risk probability of airborne virus infecting passengers in the bus, a numerical model of the bus with the refrigeration and air conditioning on in summer is established based on the numerical simulation of computational fluid dynamics (CFD) in combination with the Wells-Riley equation. Through the analysis of the characteristics of the flow field in the bus in combination with the Lagrangian method, the spread process of the droplets produced by the cough of the virus carrier in the bus is calculated. The infection risk of virus-carrying droplets to the passengers in the bus in the four ventilation mades is analyzed. It is found that the longitudinal airflow in the bus is a key factor affecting the spread of droplets. Compared with the asymmetrically arranged circular air outlets, the longitudinal airflow in the bus can be reduced by the use of slit-type air outlets. Only 6% of passengers have a higher than 5% probability of contracting diseases in the bus with displacement ventilation, which is more effective in reducing the risk of droplet-borne infection. The research results can provide guidance for the structural design of bus air supply systems and reduce the risk of droplet-borne infections.

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    Electronic Information and Electrical Engineering
    A Probe Correction Technique for Near Field to Far Field Transform Based on Sources Reconstruction Method
    YUAN Haobo, DONG Xinxin, ZHANG Ruixue, LU Lanpu, CHEN Xi
    2022, 56 (11):  1541-1546.  doi: 10.16183/j.cnki.jsjtu.2021.221
    Abstract ( 465 )   HTML ( 7 )   PDF (1218KB) ( 333 )   Save

    The sources reconstruction method (SRM) is widely applied to antenna measurement, antenna diagnostics and imaging, etc. It is a near field to far field transform, which utilizes near-field data to determine an equivalent magnetic current source over a fictitious flat surface enclosing the antenna under test. But the existing SRM is low in accuracy, since it does not have a proper probe correction algorithm. First, this paper introduces an integral equation connecting the equivalent magnetic current and the signal received by the probe according to the reciprocity theorem. Secondly, the integral equation is converted to a matrix equation by the method of moments and the magnetic current is determined by solving the matrix equation. Finally, the magnetic current leads to the pattern of the antenna under test readily. As an example, a horn is measured with a wave-guide probe and the receiving signals are processed by the proposed method to obtain the pattern, whose root mean square errors (RMSE) are only 1/3 of those of the pattern obtained by the SRM without probe correction. Therefore, the proposed probe correction algorithm is accurate and effective for the SRM.

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    Fast Construction of a Circuit Model for Via-Hole Transition Based on Liquid Crystal Polymer Multilayer Substrate
    LIU Weihong, LIU Ye
    2022, 56 (11):  1547-1553.  doi: 10.16183/j.cnki.jsjtu.2021.308
    Abstract ( 628 )   HTML ( 7 )   PDF (2713KB) ( 430 )   Save

    Liquid crystal polymer (LCP) with excellent microwave and millimeter-wave properties is widely applied in high frequency multilayer substrates. The design of an excellent via-hole transition in multilayer circuits board is important to employ as an interconnect to route signal traces on different layers or connect components. Recently, with the operating frequency increasing, the problem of discontinuity in the via-hole transition structure has become increasingly prominent. Therefore, electromagnetic modeling of via-plate-pair structures is essential for the design of microwave and millimeter-wave circuits. In this paper, an efficient and fast via-hole transition modeling method for the ground coplanar waveguide-strip line-ground coplanar waveguide(GCPW-SL-GCPW) structure based on the four-layer LCP circuit board is proposed. By segmented modeling of the multilayer structure and introducing a fast convergence algorithm in the parasitic parameter calculation process, a via-hole lumped parameter equivalent circuit structure is established. Finally, the equivalent circuit model of the GCPW-SL-GCPW structure is quickly constructed based on the microwave network cascade method. Compared with the full-wave simulation results of HFSS high frequency structure simulator, which is a 3D high-frequency electromagnetic software, it is found that this modeling process is simple and fast. The GCPW-SL-GCPW circuit structure has been fabricated using the LCP multilayer process. The test results show that the test results and the equivalent circuit analysis results are highly consistent in the wide frequency range of 10 MHz—40 GHz, which verifies the effectiveness of the via-hole transition modeling method.

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    Grammatical Error Correction by Transferring Learning Based on Pre-Trained Language Model
    HAN Mingyue, WANG Yinglin
    2022, 56 (11):  1554-1560.  doi: 10.16183/j.cnki.jsjtu.2021.079
    Abstract ( 572 )   HTML ( 9 )   PDF (700KB) ( 372 )   Save

    Grammatical error correction (GEC) is a low-resource task, which requires annotations with high costs and is time consuming in training. In this paper, the MASS-GEC is proposed to solve this problem by transferring learning from a pre-trained language generation model, and masked sequence is proposed to sequence pre-training for language generation (MASS). In addition, specific preprocessing and postprocessing strategies are applied to improve the performance of the GEC system. Finally, this system is evaluated on two public datasets and a competitive performance is achieved compared with the state-of-the-art work with limited resources. Specifically, this system achieves 57.9 in terms of F0.5 score which emphasizes more on precision on the CoNLL2014 task. On the JFLEG task, the MASS-GEC achieves 59.1 in terms of GLEU score which measures the n-gram coincidence between the output of the model and the correct answer manually annotated. This paper provides a new perspective that the low-resource problem in GEC can be solved well by transferring the general language knowledge from the self-supervised pre-trained language model.

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