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Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient
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作者 Zheng Lichang Xu Guoshan +3 位作者 Yang Ge Wang Zhen Yang Kaibo Zheng Zhenyun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期625-636,共12页
For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated.Therefore,this study prop... For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been investigated.Therefore,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation coefficient.First,the theory of the CDM for RTDST is presented.Next,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are investigated.Finally,numerical simulations and experimental tests are conducted for verifying the effectiveness of the method.The study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient increases.In most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its stability.The stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper. 展开更多
关键词 real-time dynamic substructure testing central difference method STABILITY mass participation coefficient tuned liquid damper
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Novel Real-Time Seam Tracking Algorithm Based on Vector Angle and Least Square Method 被引量:1
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作者 Guanhao Liang Qingsheng Luo +1 位作者 Zhuo Ge Xiaoqing Guan 《Journal of Beijing Institute of Technology》 EI CAS 2017年第2期150-157,共8页
Real-time seam tracking can improve welding quality and enhance welding efficiency during the welding process in automobile manufacturing.However,the teaching-playing welding process,an off-line seam tracking method,i... Real-time seam tracking can improve welding quality and enhance welding efficiency during the welding process in automobile manufacturing.However,the teaching-playing welding process,an off-line seam tracking method,is still dominant in automobile industry,which is less flexible when welding objects or situation change.A novel real-time algorithm consisting of seam detection and generation is proposed to track seam.Using captured 3D points,space vectors were created between two adjacent points along each laser line and then a vector angle based algorithm was developed to detect target points on the seam.Least square method was used to fit target points to a welding trajectory for seam tracking.Furthermore,the real-time seam tracking process was simulated in MATLAB/Simulink.The trend of joint angles vs.time was logged and a comparison between the off-line and the proposed seam tracking algorithm was conducted.Results show that the proposed real-time seam tracking algorithm can work in a real-time scenario and have high accuracy in welding point positioning. 展开更多
关键词 real-time seam tracking real-time seam detection laser scanner vector angle leastsquare method algorithm research
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Real-Time Front Vehicle Detection Algorithm Based on Local Feature Tracking Method 被引量:1
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作者 Jae-hyoung YU Young-joon HAN Hern-soo HAHN 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期244-246,共3页
This paper proposes an algorithm that extracts features of back side of the vehicle and detects the front vehicle in real-time by local feature tracking of vehicle in the continuous images.The features in back side of... This paper proposes an algorithm that extracts features of back side of the vehicle and detects the front vehicle in real-time by local feature tracking of vehicle in the continuous images.The features in back side of the vehicle are vertical and horizontal edges,shadow and symmetry.By comparing local features using the fixed window size,the features in the continuous images are tracked.A robust and fast Haarlike mask is used for detecting vertical and horizontal edges,and shadow is extracted by histogram equalization,and the sliding window method is used to compare both side templates of the detected candidates for extracting symmetry.The features for tracking are vertical edges,and histogram is used to compare location of the peak and magnitude of the edges.The method using local feature tracking in the continuous images is more robust for detecting vehicle than the method using single image,and the proposed algorithm is evaluated by continuous images obtained on the expressway and downtown.And it can be performed on real-time through applying it to the embedded system. 展开更多
关键词 vehicle detection object tracking real-time algorithm Haarlike edge detection
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A Real-time Face/Hand Tracking Method for Chinese Sign Language Recognition
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作者 刘晋东 Yuan +4 位作者 Kui Zou Wei Luo Bencheng 《High Technology Letters》 EI CAS 2002年第4期80-84,共5页
This paper introduces a new Chinese Sign Language recognition (CSLR) system and a method of real time tracking face and hand applied in the system. In the method, an improved agent algorithm is used to extract the reg... This paper introduces a new Chinese Sign Language recognition (CSLR) system and a method of real time tracking face and hand applied in the system. In the method, an improved agent algorithm is used to extract the region of face and hand and track them. Kalman filter is introduced to forecast the position and rectangle of search, and self adapting of target color is designed to counteract the effect of illumination. 展开更多
关键词 CSLR improved agent real-time tracking KALMAN FILTER
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REAL-TIME TRACKING FOR FAST MOVING OBJECT ON COMPLEX BACKGROUND 被引量:3
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作者 张超 王道波 Farooq M 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第4期321-325,共5页
A real-time tracking system for the fast moving object on the complex background is proposed.The Markov random filed(MRF)model based background subtraction algorithm is used to detect the changing pixels and track t... A real-time tracking system for the fast moving object on the complex background is proposed.The Markov random filed(MRF)model based background subtraction algorithm is used to detect the changing pixels and track the moving object.The prior probability of the segmentation mask is modeled by using MRF,and the object tracking task is translated into the maximum a-posterior(MAP)problem.Experimental results show that the method is efficient at both offline and online moving objects on simple and complex background. 展开更多
关键词 unmanned aerial vechicles real-time tracking Markov random field background subtraction
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Exploration of instantaneous frequency for local control assessment in real-time hybrid simulation
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作者 Xu Weijie Peng Changle +1 位作者 Guo Tong Chen Cheng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期995-1008,共14页
Local control parameters such as instantaneous delay and instantaneous amplitude play an essential role in evaluating the performance and maintaining the stability of real-time hybrid simulation(RTHS).However,existing... Local control parameters such as instantaneous delay and instantaneous amplitude play an essential role in evaluating the performance and maintaining the stability of real-time hybrid simulation(RTHS).However,existing methods have limitations in obtaining this local assessment in either the time domain or frequency domain.In this study,the instantaneous frequency is introduced to determine local control parameters for actuator tracking assessment in a real-time hybrid simulation.Instantaneous properties,including amplitude,delay,frequency and phase,are then calculated based on analytic signals translated from actuator tracking signals through the Hilbert transform.Potential issues are discussed and solutions are proposed for calculation of local control parameters.Numerical simulations are first conducted for sinusoidal and chirp signals with time varying amplitude error and delay to demonstrate the potential of the proposed method.Laboratory tests also are conducted for a predefined random signal as well as the RTHS of a single degree of freedom structure with a self-centering viscous damper to experimentally verify the effectiveness of the proposed use of the instantaneous frequency.Results from the ensuing analysis clearly demonstrate that the instantaneous frequency provides great potential for local control assessment,and the proposed method enables local tracking parameters with good accuracy. 展开更多
关键词 real-time hybrid simulation tracking assessment instantaneous frequency Hilbert transform
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A machine vision approach to seam tracking in real-time in PAW of large-diameter stainless steel tube 被引量:1
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作者 葛景国 朱政强 +1 位作者 何德孚 陈立功 《China Welding》 EI CAS 2004年第2期151-155,共5页
Manual monitoring and seam tracking through watching weld pool images in real-time, by naked eyes or by industrial TV, are experience-depended, subjective, labor intensive, and sometimes biased. So it is necessary to ... Manual monitoring and seam tracking through watching weld pool images in real-time, by naked eyes or by industrial TV, are experience-depended, subjective, labor intensive, and sometimes biased. So it is necessary to realize the automation of computer-aided seam tracking. A PAW (plasma arc welding) seam tracking system was developed, which senses the molten pool and the seam in one frame by a vision sensor, and then detects the seam deviation to adjust the work piece motion adaptively to the seam position sensed by vision sensor. A novel molten pool area image-processing algorithm based on machine vision was proposed. The algorithm processes each image at the speed of 20 frames/second in real-time to extract three feature variables to get the seam deviation. It is proved experimentally that the algorithm is very fast and effective. Issues related to the algorithm are also discussed. 展开更多
关键词 ALGORITHM seam tracking image processing real-time machine vision plasma arc welding
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Real-time accurate hand path tracking and joint trajectory planning for industrial robots(Ⅰ) 被引量:2
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作者 TAN Guan-zheng(谭冠政) +3 位作者 LIANG Feng(梁丰) WANG Yue-chao(王越超) 《Journal of Central South University of Technology》 2002年第3期191-196,共6页
Previously, researchers raised the accuracy for a robot′s hand to track a specified path in Car-tesian space mainly through increasing the number of knots on the path and the number of the path′s segments, which res... Previously, researchers raised the accuracy for a robot′s hand to track a specified path in Car-tesian space mainly through increasing the number of knots on the path and the number of the path′s segments, which results in the heavier online computational burden for the robot controller. Aiming at overcoming this drawback, the authors propose a new kind of real-time accurate hand path tracking and joint trajectory planning method. Through selecting some extra knots on the specified hand path by a certain rule and introducing a sinusoidal function to the joint displacement equation of each segment, this method can greatly raise the path tracking accuracy of robot′s hand and does not change the number of the path′s segments. It also does not increase markedly the computational burden of robot controller. The result of simulation indicates that this method is very effective, and has important value in increasing the application of industrial robots. 展开更多
关键词 industrial robots real-time ACCURATE HAND path tracking joint trajectory PLANNING EXTRA KNOT
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Real-time accurate hand path tracking and joint trajectory planning for industrial robots(Ⅱ)
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作者 谭冠政 胡生员 《Journal of Central South University of Technology》 EI 2002年第4期273-278,共6页
Previously, researchers raised the accuracy for a robot′s hand to track a specified path in Cartesian space mainly through increasing the number of knots on the path and the segments of the path. But, this method res... Previously, researchers raised the accuracy for a robot′s hand to track a specified path in Cartesian space mainly through increasing the number of knots on the path and the segments of the path. But, this method resulted in the heavier on line computational burden for the robot controller. In this paper, aiming at this drawback, the authors propose a new kind of real time accurate hand path tracking and joint trajectory planning method for robots. Through selecting some extra knots on the specified hand path by a certain rule, which enables the number of knots on each segment to increase from two to four, and through introducing a sinusoidal function and a cosinoidal function to the joint displacement equation of each segment, this method can raise the path tracking accuracy of robot′s hand greatly but does not increase the computational burden of robot controller markedly. 展开更多
关键词 industrial robot real-time ACCURATE HAND path tracking JOINT trajectory planning extra KNOT sinusoidal FUNCTION cosinoidal FUNCTION
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Real-time tracking of deformable objects based on MOK algorithm
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作者 Junhua Yan Zhigang Wang Shunfei Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期477-483,共7页
The traditional oriented FAST and rotated BRIEF(ORB) algorithm has problems of instability and repetition of keypoints and it does not possess scale invariance. In order to deal with these drawbacks, a modified ORB... The traditional oriented FAST and rotated BRIEF(ORB) algorithm has problems of instability and repetition of keypoints and it does not possess scale invariance. In order to deal with these drawbacks, a modified ORB(MORB) algorithm is proposed. In order to improve the precision of matching and tracking, this paper puts forward an MOK algorithm that fuses MORB and Kanade-Lucas-Tomasi(KLT). By using Kalman, the object's state in the next frame is predicted in order to reduce the size of search window and improve the real-time performance of object tracking. The experimental results show that the MOK algorithm can accurately track objects with deformation or with background clutters, exhibiting higher robustness and accuracy on diverse datasets. Also, the MOK algorithm has a good real-time performance with the average frame rate reaching 90.8 fps. 展开更多
关键词 Kalman prediction oriented FAST and rotated BRIEF(ORB) match deformation real-time tracking
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Real-time localization for underwater equipment using an extremely low frequency electric field 被引量:1
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作者 Jia-wei Zhang Peng Yu +1 位作者 Run-xiang Jiang Tao-tao Xie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期203-212,共10页
A new real-time underwater equipment location method adopting an electric field induced by a standard current source is proposed.Our goals were real-time tracking and location of stationary or moving underwater equipm... A new real-time underwater equipment location method adopting an electric field induced by a standard current source is proposed.Our goals were real-time tracking and location of stationary or moving underwater equipment both in shallow and deep seas,under noisy conditions.The main features of this method are as follows:(1)a standard current source on the water surface,which can be towed by a vehicle,consisting of two electrodes,a signal generator,and a GPS unit;(2)measurement of the extremely low frequency(ELF)electric field emitted by the current source,made possible by electric field sensors on the underwater equipment;(3)position of the underwater equipment is estimated in real time based on a progressive update extended Kalman filter(PUEKF),which is carried out using the propagation model of an ELF electric field because the electric field at the position of the underwater equipment and the current source position are known.We verified the accuracy of our method and confirmed real-time location feasibility through numerical,physical scale,and real-time sea experiments.Through numerical experiments,we verified that our method works for underwater equipment location in real-world conditions,and the location error can be less than 0.2 m.Next,real-time location experiments for stationary underwater measuring equipment in water tank were conducted.The result shows that the location error can be less than 0.1 m.We also confirmed real-time location feasibility through the use of offshore experiment.We expect that our method will complement conventional underwater acoustic location methods for underwater equipment in acoustically noisy environments. 展开更多
关键词 Termsd real-time tracking and location method Underwater equipment location ELF electric field Shallow sea Physical scale experiment Sea experiment
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Fast-moving target tracking based on mean shift and frame-difference methods 被引量:32
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作者 Hongpeng Yin Yi Chai +1 位作者 Simon X. Yang Xiaoyan Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期587-592,共6页
The mean shift tracker has difficulty in tracking fast moving targets and suffers from tracking error accumulation problem. To overcome the limitations of the mean shift method, a new approach is proposed by integrati... The mean shift tracker has difficulty in tracking fast moving targets and suffers from tracking error accumulation problem. To overcome the limitations of the mean shift method, a new approach is proposed by integrating the mean shift algorithm and frame-difference methods. The rough position of the moving tar- get is first located by the direct frame-difference algorithm and three-frame-difference algorithm for the immobile camera scenes and mobile camera scenes, respectively. Then, the mean shift algorithm is used to achieve precise tracking of the target. Several tracking experiments show that the proposed method can effectively track first moving targets and overcome the tracking error accumulation problem. 展开更多
关键词 mean shift frame-difference method target tracking computer vision.
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A GHOST FLUID BASED FRONT TRACKING METHOD FOR MULTIMEDIUM COMPRESSIBLE FLOWS 被引量:3
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作者 王东红 赵宁 +1 位作者 胡偶 刘剑明 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1629-1646,共18页
Recent years the modify ghost fluid method (MGFM) and the real ghost fluid method (RGFM) based on Riemann problem have been developed for multimedium compressible flows. According to authors, these methods have on... Recent years the modify ghost fluid method (MGFM) and the real ghost fluid method (RGFM) based on Riemann problem have been developed for multimedium compressible flows. According to authors, these methods have only been used with the level set technique to track the interface. In this paper, we combine the MCFM and the RGFM respectively with front tracking method, for which the fluid interfaces are explicitly tracked by connected points. The method is tested with some one-dimensional problems, and its applicability is also studied. Furthermore, in order to capture the interface more accurately, especially for strong shock impacting on interface, a shock monitor is proposed to determine the initial states of the Riemann problem. The present method is applied to various one- dimensional problems involving strong shock-interface interaction. An extension of the present method to two dimension is also introduced and preliminary results are given. 展开更多
关键词 front tracking method ghost fluid method multimedium compressible flow Riemann problem
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Real-time embedded software testing method based on extended finite state machine 被引量:6
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作者 Yongfeng Yin Bin Liu Hongying Ni 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期276-285,共10页
The reliability of real-time embedded software directly determines the reliability of the whole real-time embedded sys- tem, and the effective software testing is an important way to ensure software quality and reliab... The reliability of real-time embedded software directly determines the reliability of the whole real-time embedded sys- tem, and the effective software testing is an important way to ensure software quality and reliability. Based on the analysis of the characteristics of real-time embedded software, the formal method is introduced into the real-time embedded software testing field and the real-time extended finite state machine (RT-EFSM) model is studied firstly. Then, the time zone division method of real-time embedded system is presented and the definition and description methods of time-constrained transition equivalence class (timeCTEC) are presented. Furthermore, the approaches of the testing sequence and test case generation are put forward. Finally, the proposed method is applied to a typical avionics real- time embedded software testing practice and the examples of the timeCTEC, testing sequences and test cases are given. With the analysis of the testing result, the application verification shows that the proposed method can effectively describe the real-time embedded software state transition characteristics and real-time requirements and play the advantages of the formal methods in accuracy, effectiveness and the automation supporting. Combined with the testing platform, the real-time, closed loop and automated simulation testing for real-time embedded software can be realized effectively. 展开更多
关键词 real-time system real-time embedded software for- mal method extended finite state machine (EFSM) testing se- quence test case.
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A STUDY ON THE ENSEMBLE FORECAST REAL-TIME CORRECTION METHOD 被引量:4
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作者 GUO Rong QI Liang-bo +1 位作者 GE Qian-qian WENG Yong-yuan 《Journal of Tropical Meteorology》 SCIE 2018年第1期42-48,共7页
Using real-time correction technology for typhoons, this paper discusses real-time correction for forecasting the track of four typhoons during 2009 and 2010 in Japan, Beijing, Guangzhou, and Shanghai. It was determin... Using real-time correction technology for typhoons, this paper discusses real-time correction for forecasting the track of four typhoons during 2009 and 2010 in Japan, Beijing, Guangzhou, and Shanghai. It was determined that the short-time forecast effect was better than the original objective mode. By selecting four types of integration schemes after multiple mode path integration for those four objective modes, the forecast effect of the multi-mode path integration is better, on average, than any single model. Moreover, multi-mode ensemble forecasting has obvious advantages during the initial 36 h. 展开更多
关键词 typhoon path real-time correction ensemble forecast track errors
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A Time Neighborhood Method for the Verification of Landfalling Typhoon Track Forecast
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作者 Daosheng XU Jeremy Cheuk-Hin LEUNG Banglin ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第2期273-284,共12页
Landfalling typhoons can cause disasters over large regions.The government and emergency responders need to take measures to mitigate disasters according to the forecast of landfall position,while slight timing error ... Landfalling typhoons can cause disasters over large regions.The government and emergency responders need to take measures to mitigate disasters according to the forecast of landfall position,while slight timing error can be ignored.The reliability of operational model forecasts of typhoon landfall position needs to be evaluated beforehand,according to the forecasts and observation of historical cases.In the evaluation of landfalling typhoon track,the traditional method based on point-to-point matching methods could be influenced by the predicted typhoon translation speed.Consequently,the traditional track evaluation method may result in a large track error even if the predicted landfall position is close to observation.The purpose of this paper is to address the above issue using a simple evaluation method of landfalling typhoon track forecast based on the time neighborhood approach.In this new method,the timing error was lessened to highlight the importance of the position error during the landfall of typhoon.The properties of the time neighborhood method are compared with the traditional method based on numerical forecast results of 12 landfalling typhoon cases.Results demonstrated that the new method is not sensitive to the sampling frequency,and that the difference between the time neighborhood and traditional method will be more obvious when the moving speed of typhoon is moderate(between 15−30 km h^(−1)).The time neighborhood concept can be easily extended to a broader context when one attempts to examine the position error more than the timing error. 展开更多
关键词 time neighborhood method typhoon track landfalling typhoon model evaluation
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Multiple-Object Tracking Using Histogram Stamp Extraction in CCTV Environments
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作者 Ye-Yeon Kang Geon Park +1 位作者 Hyun Yoo Kyungyong Chung 《Computers, Materials & Continua》 SCIE EI 2023年第12期3619-3635,共17页
Object tracking,an important technology in the field of image processing and computer vision,is used to continuously track a specific object or person in an image.This technology may be effective in identifying the sa... Object tracking,an important technology in the field of image processing and computer vision,is used to continuously track a specific object or person in an image.This technology may be effective in identifying the same person within one image,but it has limitations in handling multiple images owing to the difficulty in identifying whether the object appearing in other images is the same.When tracking the same object using two or more images,there must be a way to determine that objects existing in different images are the same object.Therefore,this paper attempts to determine the same object present in different images using color information among the unique information of the object.Thus,this study proposes a multiple-object-tracking method using histogram stamp extraction in closed-circuit television applications.The proposed method determines the presence or absence of a target object in an image by comparing the similarity between the image containing the target object and other images.To this end,a unique color value of the target object is extracted based on its color distribution in the image using three methods:mean,mode,and interquartile range.The Top-N accuracy method is used to analyze the accuracy of each method,and the results show that the mean method had an accuracy of 93.5%(Top-2).Furthermore,the positive prediction value experimental results show that the accuracy of the mean method was 65.7%.As a result of the analysis,it is possible to detect and track the same object present in different images using the unique color of the object.Through the results,it is possible to track the same object that can minimize manpower without using personal information when detecting objects in different images.In the last response speed experiment,it was shown that when the mean was used,the color extraction of the object was possible in real time with 0.016954 s.Through this,it is possible to detect and track the same object in real time when using the proposed method. 展开更多
关键词 Data mining deep learning object detection object tracking real-time object detection multiple object image processing
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Particle path tracking method in two- and three-dimensional continuously rotating detonation engines 被引量:1
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作者 周蕊 武丹 +1 位作者 刘岩 王健平 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期307-315,共9页
The particle path tracking method is proposed and used in two-dimensional(2D) and three-dimensional(3D) numerical simulations of continuously rotating detonation engines(CRDEs). This method is used to analyze th... The particle path tracking method is proposed and used in two-dimensional(2D) and three-dimensional(3D) numerical simulations of continuously rotating detonation engines(CRDEs). This method is used to analyze the combustion and expansion processes of the fresh particles, and the thermodynamic cycle process of CRDE. In a 3D CRDE flow field, as the radius of the annulus increases, the no-injection area proportion increases, the non-detonation proportion decreases, and the detonation height decreases. The flow field parameters on the 3D mid annulus are different from in the 2D flow field under the same chamber size. The non-detonation proportion in the 3D flow field is less than in the 2D flow field. In the 2D and 3D CRDE, the paths of the flow particles have only a small fluctuation in the circumferential direction. The numerical thermodynamic cycle processes are qualitatively consistent with the three ideal cycle models, and they are right in between the ideal F–J cycle and ideal ZND cycle. The net mechanical work and thermal efficiency are slightly smaller in the 2D simulation than in the 3D simulation. In the 3D CRDE, as the radius of the annulus increases, the net mechanical work is almost constant, and the thermal efficiency increases. The numerical thermal efficiencies are larger than F–J cycle, and much smaller than ZND cycle. 展开更多
关键词 continuously rotating detonation engine thermodynamic cycle numerical simulation particle path tracking method
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Trajectory tracking and obstacle avoidance method for robots based on fast terminal sliding mode 被引量:4
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作者 CAO Zhi-bin YANG Wei +1 位作者 SHAO Xing-ling LIU Ning 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第1期78-86,共9页
For accurate trajectory tracking and obstacle avoidance in finite time of a nonholonomic mobile robot,a trajectory tracking controller based on global fast terminal sliding mode method is proposed,which has the advant... For accurate trajectory tracking and obstacle avoidance in finite time of a nonholonomic mobile robot,a trajectory tracking controller based on global fast terminal sliding mode method is proposed,which has the advantages of chattering-free and adjustable convergence time.First of all,the kinematics model of the robot is established in mobile carrier coordinates.Secondly,the global structure including terminal attractor and exponential convergence of the fast terminal sliding mode trajectory tracking controller is proved by Lyapunov stability theory,ensuring that the trajectory and heading angle tracking error converges to a smaller zero range in finite time.Finally,the artificial potential field obstacle avoidance method is introduced to make the robot not only track the reference trajectory strictly,but also avoid the obstacles.The simulation results show that the proposed method can achieve a stable tracking control in finite time for a given reference trajectory. 展开更多
关键词 trajectory tracking global fast terminal sliding mode adjustable convergence time chattering free artificial potential field method
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Comparison of delay compensation methods for real-time hybrid simulation using frequency-domain evaluation index 被引量:2
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作者 Xu Weijie Guo Tong Chen Cheng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第1期129-143,共15页
The delay compensation method plays an essential role in maintaining the stability and achieving accurate real-time hybrid simulation results. The effectiveness of various compensation methods in different test scenar... The delay compensation method plays an essential role in maintaining the stability and achieving accurate real-time hybrid simulation results. The effectiveness of various compensation methods in different test scenarios, however, needs to be quantitatively evaluated. In this study, four compensation methods (i.e., the polynomial extrapolation, the linear acceleration extrapolation, the inverse compensation and the adaptive inverse compensation) are selected and compared experimentally using a frequency evaluation index (FEI) method. The effectiveness of the FEI method is first verified through comparison with the discrete transfer fimction approach for compensation methods assuming constant delay. Incomparable advantage is further demonstrated for the FEI method when applied to adaptive compensation methods, where the discrete transfer function approach is difficult to implement. Both numerical simulation and laboratory tests with predefined displacements are conducted using sinusoidal signals and random signals as inputs. Findings from numerical simulation and experimental results demonstrate that the FEI method is an efficient and effective approach to compare the performance of different compensation methods, especially for those requiring adaptation of compensation parameters. 展开更多
关键词 real-time hybrid simulation frequency domain evaluation index delay compensation methods
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