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Modified Hough Transform Based Registration Method for Heavy-haul Railway Rail Profile with Intensive Environmental Noise

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IEEE Transactions on Instrumentation and Measurement 2025年

作者： An, Yuntong Cao, Yuan Sun, Yongkui Su, Shuai Wang, Feng Beijing Jiaotong University National Engineering Research Center of Rail Transportation Operation Control System School of Automation and Intelligent Beijing100044 China Beijing Jiaotong University Frontiers Science Center for Smart High-speed Railway System Beijing100044 China Beijing Jiaotong University State Key Laboratory of Advanced Rail Autonomous Operation Beijing100044 China

In heavy-haul railway inspections, accurate rail profile registration is essential for assessing wear and deformation of tracks. In this process, identifying the rail waist arc as key segments and determining the center of the arc as feature points are crucial steps for rough rail profile registration, often affected by noise from sensors, surface contaminants, and environmental factors. To address these challenges, a profile registration method is proposed, with the Modified Hough Transform (MHT) as a core component. The method first segments key profile sections using curvature thresholds to identify arc segments. For each point in these segments, MHT constructs circles with fixed radius and calculates their intersection points. A distance matrix based on Euclidean distances between intersection points is generated. By sorting and normalizing these distances, the method identifies local density variations and calculates density coefficients to find the circle center, without manual thresholding. Comparative experiments on simulated and field data show that the proposed method achieves high accuracy and robustness in noisy environments. The dual validation confirms its reliability, making this method effective for rail profile registration in heavy-haul railway inspections. © 1963-2012 IEEE.

关键词： Hough transforms

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InGaAlAs/InP MQW transistor lasers based on step-ridge waveguides

IEEE Electron Device Letters

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IEEE Electron Device Letters 2025年

作者： Liu, Yijia Qiao, Lijun Tang, Xin Liang, Song Zhang, Mingjiang Taiyuan University of Technology College of Physics and Optoelectronics Taiyuan030024 China Ministry of Education Taiyuan University of Technology Key Laboratory of Advanced Transducers and Intelligent Control System Shanxi Taiyuan030024 China Chinese Academy of Sciences Key Laboratory of Optoelectronic Materials and Devices Beijing100083 China University of Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering Beijing100049 China

We propose and numerically investigate a new step-ridge-waveguide InGaAlAs/InP multi-quantum well (MQW) transistor laser (TL). The carrier nonradiative recombination centers caused by the exposed deep-ridge waveguide sidewall significantly degrade the optoelectronic performance of the TLs. The step-ridge-waveguide structure guides carriers through the center portion of the ridge waveguide, thereby effectively mitigating the effect of the nonradiative recombination defects. Simulation results show that the optoelectronic characteristics of the step-ridge TL are far better than those of the conventional deep-ridge TL, and the current amplification factor of the step-ridge TL is not affected by the laser excitation. This structure provides a new option for the simultaneous enhancement of the optoelectronic performance of TLs. © 1980-2012 IEEE.

关键词： Laser excitation

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Integrating mobile and fixed monitoring data for high-resolution PM2.5 mapping using machine learning

arXiv

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arXiv 2025年

作者： Xu, Rui Yao, Dawen Pian, Yuzhuang Cao, Ruhui Fu, Yixin Yang, Xinru Gan, Ting Liu, Yonghong School of Intelligent Systems Engineering Sun Yat-sen University Guangdong Shenzhen518107 China Guangdong Provincial Key Laboratory of Intelligent Transportation System Sun Yat-Sen University Guangzhou510275 China Guangdong Provincial Engineering Research Center for Traffic Environmental Monitoring and Control Guangdong Guangzhou510275 China

Constructing high resolution air pollution maps at lower cost is crucial for sustainable city management and public health risk assessment. However, traditional fixed-site monitoring lacks spatial coverage, while mobile low-cost sensors exhibit significant data instability. This study integrates PM2.5 data from 320 taxi-mounted mobile low-cost sensors and 52 fixed monitoring stations to address these limitations. By employing the machine learning methods, an appropriate mapping relationship was established between fixed and mobile monitoring concentration. The resulting pollution maps achieved 500-meter spatial and 5-minute temporal resolutions, showing close alignment with fixed monitoring data (+4.35% bias) but significant deviation from raw mobile data (-31.77%). The fused map exhibits the fine-scale spatial variability also observed in the mobile pollution map, while showing the stable temporal variability closer to that of the fixed pollution map (fixed: 1.12±0.73%, mobile: 3.15±2.44%, mapped: 1.01±0.65%). These findings demonstrate the potential of large-scale mobile low-cost sensor networks for high-resolution air quality mapping, supporting targeted urban environmental governance and health risk mitigation. © 2025, CC BY.

关键词： Environmental monitoring

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Near minimum-time feedback attitude control with multiple saturation constraints for agile satellites

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Chinese Journal of Aeronautics 2016年第3期29卷 722-737页

作者： Liu Xiangdong Xin Xing Li Zhen Chen Zhen Sheng Yongzhi School of Automation Beijing Institute of Technology National Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology

Agile satellites are of importance in modern aerospace applications, but high mobility of the satellites may cause them vulnerable to saturation during attitude maneuvers due to limited rating of actuators, This paper proposes a near minimum-time feedback control law for the agile satellite attitude control system. The feedback controller is formed by specially designed cascaded sub-units. The rapid dynamic response of the modified Bang Bang control logic achieves the near optimal property and ensures the non-saturation properties on three-axis. To improve the dynamic performance, a model reference control strategy is proposed, in which the oniline near optimal attitude maneuver path is generated by the cascade controller and is then tracked by a nonlinear back-stepping controller. Furthermore, the accuracy and the robustness of the control system are achieved by momentum-based on-line inertial identification. The rapid attitude maneuvering can be applied for tasks including the move to move case. Numerical simulations are conducted to verify the effectiveness of the proposed control strategy in terms of the saturation-free property and rapidness.

关键词： Actuator saturation Attitude control Identification Momentum transfer Satellites

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Research on Temperature Error Calibration Method of Fluxgate Sensor

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Journal of Advanced Computational Intelligence and intelligent Informatics 2025年第3期29卷 583-591页

作者： Yang, Ruiping Ge, Jian Luo, Wang Hu, Xiangyun She, Jinhua Chugo, Daisuke Dong, Haobin School of Automation China University of Geosciences No.388 Lumo Road Hongshan District Hubei Wuhan430074 China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems No.388 Lumo Road Hongshan District Hubei Wuhan430074 China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education No 388 Lumo Road Hongshan District Hubei Wuhan430074 China School of Engineering Kwansai Gakuin University 1 Gakuen Uegahara Hyogo Sanda669-1330 Japan School of Geophysics and Geomatics China University of Geosciences No.388 Lumo Road Hongshan District Hubei Wuhan430074 China Hubei Subsurface Multi-scale Imaging Key Laboratory No.388 Lumo Road Hongshan District Hubei Wuhan430074 China School of Engineering Tokyo University of Technology 1404-1 Katakuramachi Hachioji Tokyo192-0982 Japan

The fluxgate sensor is the most widely used sensor in vector magnetic measurement. However, during long-term continuous observation, the fluxgate sensor will produce large measurement errors due to changes in ambient temperature. This paper proposes a temperature calibration method for the fluxgate sensor based on polynomial fitting to address the temperature error of fluxgate sensors. First, the effect of temperature on the performance indicators of the fluxgate sensor was analyzed. Second, according to the existing temperature-magnetic field data, a temperature calibration model of the fluxgate sensor was constructed. Compared with other temperature calibration methods, the result shows that the proposed temperature calibration method is relatively simple and can better achieve real-time calibration for sensor application scenarios. Finally, to verify the effectiveness of the proposed method, numerous laboratory experiments were implemented. The temperature drift was reduced from about 700 nT before calibration to about 1 nT, root mean square error RMSE = 11.7189, indicating that the proposed method has a good temperature calibration effect on the data measured by the fluxgate sensor within the variable temperature background. © Fuji Technology Press Ltd.

关键词： Magnetic field measurement

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control method on serial type pump-valve coordinated electro-hydraulic servo system

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Journal of Beijing Institute of Technology 2016年第1期25卷 100-107页

作者：谢文汪首坤王军政吴建 Key Laboratory of Intelligent Control and Decision of Complex System School of AutomationBeijing Institute of Technology

In order to compromise the conflicts between control accuracy and system efficiency of conventional electro-hydraulic servo systems,a novel pump-valve coordinated electro-hydraulic servo system was designed and a corresponding control strategy was *** system was constituted of a pumpcontrolled part and a valve-controlled part,the pump controlled part is used to adjust the flow rate of oil source and the valve controlled part is used to complete the position tracking control of the hydraulic *** on the system characteristics,a load flow grey prediction method was adopted in the pump controlled part to reduce the system overflow losses,and an adaptive robust control method was adopted in the valve controlled part to eliminate the effect of system nonlinearity and parametric uncertainties due to variable hydraulic parameters and system loads on the control *** experimental results validated that the adopted control strategy increased the system efficiency obviously with guaranteed high control accuracy.

关键词： pump-valve coordinated grey prediction adaptive robust control efficiency

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Localization and mapping in urban area based on 3D point cloud of autonomous vehicles

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Journal of Beijing Institute of Technology 2016年第4期25卷 473-482页

作者：王美玲李玉杨毅朱昊刘彤 Key Laboratory of Intelligent Control and Decision of Complex System School of AutomationBeijing Institute of Technology

In order to meet the application requirements of autonomous vehicles, this paper proposes a simultaneous localization and mapping （SLAM） algorithm, which uses a VoxelGrid filter to down sample the point cloud data, with the combination of iterative closest points （ICP） algorithm and Gaussian model for particles updating, the matching between the local map and the global map to quantify particles＇ importance weight. The crude estimation by using ICP algorithm can find the high probability area of autonomous vehicles＇ poses, which would decrease particle numbers, increase algorithm speed and restrain particles＇ impoverishment. The calculation of particles＇ importance weight based on matching of attribute between grid maps is simple and practicable. Experiments carried out with the autonomous vehicle platform validate the effectiveness of our approaches.

关键词： simultaneous localization and mapping （SLAM） Rao-Blackwellized particle filter （ RB-PF） VoxelGrid filter ICP algorithm Gaussian model urban area

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Adaptive robust control for electrical cylinder with friction compensation usingmodified LuGre model

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Journal of Beijing Institute of Technology 2014年第3期23卷 358-367页

作者：郝仁剑王军政赵江波汪首坤 Key Laboratory of Intelligent Control and Decision of Complex System School of AutomationBeijing Institute of Technology

The position tracking control problem of an electrical cylinder in the presence of dynamic friction nonlinearities in its transmission process is addressed in this paper. First, a torque decou- piing approach is proposed to formulate the dynamic model. Secondly, to compensate the friction in the case of servo motion, a modified LuGre model is designed to make a continuous transition be- tween a static model at a high speed and a LuGre model at a low speed to avoid instability due to dis- cretization with a finite sampling rate. To accelerate the speed of estimating time-varying parame- ters, a fast adaption law is proposed by designing an attraction domain around a rough value related to the load force. Finally, a discontinuous projection based adaptive robust controller is synthesized to effectively handle parametric uncertainties for ensuring a guaranteed robust performance. A Lya- punov stability analysis demonstrates that all signals including tracking errors have the guaranteed convergent and bounded performance. Extensive comparative simulations with sinusoidal and point- point tracks are obtained respectively in low and high speeds. The results show the effectiveness and the achievable control performance of the proposed control strategy.

关键词： adaptive robust electrical cylinder friction compensation LuGre model

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Novel algorithm of gait planning of hydraulic quadruped robot to avoid foot slidingand reduce impingement

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Journal of Beijing Institute of Technology 2016年第1期25卷 91-99页

作者：马立玲杨超峰王立鹏王军政 Key Laboratory of Intelligent Control and Decision of Complex System School of AutomationBeijing Institute of Technology

In order to solve kinematic redundancy problems of a hydraulic quadruped walking robot,which include leg dragging,sliding,impingement against the ground,an improved gait planning algorithm for this robot is proposed in this ***,the foot trajectory is designated as the improved composite cycloid foot ***,the landing angle of each leg of the robot is controlled to satisfy friction cone to improve the stability performance of the *** with the controllable landing angle of quadruped robot and a geometry method,the kinematic equation is derived in this ***,agait planning method of quadruped robot is proposed,a dynamic co-simulation is done with ADAMS and MATLAB,and practical experiments are *** validity of the proposed algorithm is confirmed through the co-simulation and *** results show that the robot can avoid sliding,reduce impingement,and trot stably in trot gait.

关键词： landing angle gait planning foot trajectory friction cone sliding impingement

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Optimal Tuning of Plant-Friendly PID controllers

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Journal of Beijing Institute of Technology 2010年第3期19卷 331-336页

作者：史大威王军政马立玲 Key Laboratory of Complex System Intelligent Control and Decision School of AutomationBeijing Institute of Technology

A plant-friendly proportional-integral-derivative （PID） controller optimization framework is proposed to make tradeoffs among set-point response,controller output variations and *** objective function is chosen as the weighted sum of the integral of squared time-weighted error and the integral of squared timeweighted derivative of the control variable with respect to set-point response,while the robustness of the system is guaranteed by constraints on gain and phase *** to the complex structure of the constraints,the problem is solved by genetic *** analysis show the proposed method could efficiently reduce the controller output variations while maintaining a short settling *** on the simulation results,iterative tuning rules for the weighting factor in the objective function are obtained,which allows efficient simple proportional-integral（PI） tuning formulae to be derived.

关键词： PID control plant-friendliness genetic algorithm constrained optimization

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