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Energy-Based Trajectory Tracking for Underactuated Mechanical Systems: Velocity-Free and Disturbance Rejection Methods

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International Journal of Robust and Nonlinear control 2025年

作者： Javanmardi, N. Borja, P. van der Schaft, A.J. Yazdanpanah, M.J. Scherpen, J.M.A. Jan C. Willems Center for Systems and Control ENTEG Faculty of Science and Engineering University of Groningen Groningen Netherlands Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran Iran School of Engineering Computing and Mathematics University of Plymouth Plymouth United Kingdom Jan C. Willems Center for Systems and Control Bernoulli Institute Faculty of Science and Engineering University of Groningen Groningen Netherlands

This work investigates three energy-shaping control approaches to address the trajectory-tracking problem for specific classes of underactuated mechanical systems. In particular, the notions of contractive systems and dynamic extensions are utilized to solve the trajectory-tracking problem while addressing implementation issues such as the lack of velocity sensors and the presence of constant disturbances. To this end, a first tracking controller is developed without the need for velocity measurements. A second controller is introduced, solving the trajectory-tracking problem while rejecting matched constant disturbances. Then, a third approach establishes conditions to combine both mentioned controllers. It is shown that the proposed design methods guarantee exponential convergence of closed-loop systems for specific classes of underactuated mechanical systems. The third method is illustrated with an example. © 2025 The Author(s). International Journal of Robust and Nonlinear control published by John Wiley & Sons Ltd.

关键词： Disturbance rejection

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Robust eigenstructure assignment: New approach

Robust eigenstructure assignment: New approach

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作者： Ashari, Alireza Esna Control and Intelligent Processing Center of Excellence University of Tehran Tehran Iran

ISBN: (纸本)008045108X

This paper considers the problem of robust eigenstructure assignment, which involves finding a feedback gain matrix that makes the closed-loop system insensitive to perturbations or parameter variations. The main contribution of the paper is to derive a new robustness measure using the matrix perturbation theory. The new measure is used to formulate a new method for robust control of the system via state or output feedback. The freedom provided by eigenvalue assignment of multivariable systems is applied to optimize the new index using genetic algorithms. The new results expressed in this paper confirm the previously derived results on robust eigenstructure assignment. in the case of state feedback design, the new robustness index verifies a previously proposed robustness measure. A numerical example is presented to illustrate the effectiveness of the proposed method. Copyright © 2005 IFAC.

关键词： Genetic algorithms

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An investigation on the usage of image quality assessment in visual speech recognition

An investigation on the usage of image quality assessment in...

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2010 3rd International Congress on Image and Signal processing, CISP 2010

作者： Banitalebi, Amin Moosaei, Maryam Hossein-Zadeh, Gholam Ali Control and Intelligent Processing Center of Excellence College of Engineering University of Tehran Iran

ISBN: (纸本)9781424465149

Having a robust speech recognition scheme that can be relied upon in different environments is a strong requirement for modern systems. Previous works in field of lipreading mainly have used a level of segmentation at the beginning and then used the structure of the mouth, facial muscles of the speaker, some critical points on the lip, or the motion of these points for word recognition. In this paper we present a novel way of processing the video signal for lipreading application. We neither used segmentation level nor the extraction of important facial points. Instead, we've used HVS (human visual system) based image quality metrics, especially complex wavelet structural similarity (CW-SSIM) and visual information fidelity (VIF) as our similarity criterions. We used an intelligent frame by frame video comparison technique and we applied mentioned metrics in our approach. Experimental results showed that in comparison to other methods, this novel method can recognize the true letter among the letters of the utilized dictionary with an acceptable accuracy. ©2010 IEEE.

关键词： Image quality

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Second-order EKF and unscented Kalman filter fusion for tracking maneuvering targets

Second-order EKF and unscented Kalman filter fusion for trac...

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2007 IEEE International Conference on Information Reuse and Integration, IEEE IRI-2007

作者： Sadeghi, Behrooz Moshiri, Behzad Control and Intelligent Processing Center of Excellence University of Tehran Tehran Iran IEEE

ISBN: (纸本)1424414997

When dealing with target tracking problem for maneuvering targets, it may be the case that a first order extended Kalman filter can not track the target and diverges due to neglecting the higher order terms of Taylor series. This paper studies two other filters which are more appropriate for maneuvering targets (with nonlinear state space equations). These two filters are entitled as second-order extended Kalman filter (SOEKF) and unscented Kalman filter (UKF). SOEKF uses Hessian matrix (second term of Taylor series) which may help solving the divergence problem. UKF is also useful as it works with the main nonlinear formula without the need to use any approximation. Both of the state space equations (process equation and measurement equation) is assumed to be nonlinear. In order to enhance the accuracy of tracking process sensor fusion approach is also applied for both of the filters. The number of sensors is assumed to be two. A comparison analysis is made between the two filters alone (without fusion approach) and also when sensor fusion is applied. © 2007 IEEE.

关键词： Extended Kalman filters

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Time series analysis of the Twinkling Artifact in color Doppler sonography for surface roughness differentiation: An in vitro feasibility study

Time series analysis of the Twinkling Artifact in color Dopp...

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2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013

作者： Akbarifar, Faranak Jamzad, Amoon Setarehdan, Seyed Kamaledin Control and Intelligent Processing Center of Excellence College of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9781479932320

Color Doppler Twinkling Artifact (TA) images acquired from the internal body stones contain coded information about the roughness level of the tissue calculi which can be used for treatment management. The TA time series however have never been mathematically studied for roughness identification. This paper investigates the feasibility of estimating the roughness level of a surface by analyzing its TA time series. The TA data of a roughness phantom was used in this study in 2 classes and 1000 TA time series were extracted for each of the classes. Then, three subsets of temporal, spectral, and wavelet features were extracted from each time series. Next, the Bayesian and Support Vector Machines (SVM) classifiers were employed for roughness differentiations. The performance of the proposed method was investigated for cross-comparison of feature subsets, classifiers, and dimension reduction efficiency. Results showed that with only first two principle components projected from the extracted features, an accuracy of 96.06% was obtained which proves the feasibility of roughness recognition by time series analysis of the TA data. © 2013 IEEE.

关键词： Biomedical signal processing

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Heart sound segmentation based on recurrence time statistics

Heart sound segmentation based on recurrence time statistics

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2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013

作者： Zaeemzadeh, Alireza Nafar, Zahra Setarehdan, Seyed-Kamaledin Control and Intelligent Processing Center of Excellence College of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9781479932320

Heart sound segmentation is the primary step in automatic diagnosis of heart sounds. Since heart sound components have great diversity in frequency and amplitude, the focus of this paper is on time domain analysis. Time intervals between consequent peaks have been clustered in time domain and statistical data were extracted. Then a reference point was labeled by using the clustered data. We propose a novel algorithm to segment the heart sound signals, by using extracted data and the reference point. The performance of the algorithm has been evaluated using 240 periods of heart sound signals recorded from 12 subjects including normal and abnormal sounds. The algorithm has achieved a 93.8 percent precision and 100 percent of sensitivity during evaluation. © 2013 IEEE.

关键词： Time domain analysis

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A distributed deterministic help scheme to improve the system fault tolerance

A distributed deterministic help scheme to improve the syste...

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intelligent Automation and control Trends, Principles, and Applications - International Symposium on intelligent Automation and control, ISIAC - Sixth Biannual World Automation Congress, WAC 2004

作者： Mirian, Maryam S. Ahmadabadi, Majid Nili Dept. of ECE Control and Intelligent Processing Center of Excellence University of Tehran Iran

ISBN: (纸本)1889335223

This paper proposes some methods to improve the fault-tolerance in distributed systems specifically in deterministic situations by distributed decision-making and co-ordination. Providing a distributed system with fault tolerance is a feasible but hard problem due to the intrinsic aspects of such systems such as: independency, unpredictability and communication problem. A multi-agent system as an instance of distributed system, can handle different kinds of fault by using traditional fault tolerance techniques. But what 'focused in this paper are agent-based techniques. In fact, proposed methods are based on agent-based help provision by distributed cooperation among helper agents. The helpers try to tune their normal roles such that they can undertake the faulty agents' tasks too. These helpers go through a sub-optimal task selection algorithm, to decide whom to help. It is important to remark that there is no explicit interaction;instead they coordinate their decisions implicitly by adopting the most appropriate task in terms of their speed, relative reliability and the task's criticality coefficient. Proposed ideas are tested on a DCS-like testbed to improve its fault tolerance. The results illustrate the effectiveness of the approaches in comparison to the case of no help situation and the case of using purely redundant components.

关键词： Multi agent systems

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Adaptation of personality-based decision making to crowd behavior simulations

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13th International Conference on Artificial Intelligence: Methodology, Systems, and Applications, AIMSA 2008

作者： Alavizadeh, Fatemeh Lucas, Caro Moshiri, Behzad Control and Intelligent Processing Center of Excellence School of ECE University of Tehran Tehran Iran

ISBN: (纸本)3540857753

Simulation of crowd behaviors in emergency contexts is a critical issue concerning human lives. However, lack of human behavioral data in most of current simulation tools made them unrealistic. This is partially because of instability in the theoretical issues due to complexity of human behavior, and partially because of the gap between theories and what that can be implemented in agent environments. This research is an effort to investigate a system for realistic and intelligent crowd simulations based on personality, age, and gender of individuals. The model demonstrates some emergent behaviors, such as competitive pushing, queuing, and herding. © Springer-Verlag Berlin Heidelberg 2008.

关键词： Decision making

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An adaptive Neuro-Fuzzy inference system for diagnosis of Aphasia

An adaptive Neuro-Fuzzy inference system for diagnosis of Ap...

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2nd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2008

作者： Fazeli, Sepideh Naghibolhosseini, Maryam Bahrami, Fariba Center of Excellence: Control and Intelligent Processing College of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9781424417483

Aphasia is a language disability that has several subdivisions such as Anomic, Broca, Global, and Wernicke. Some reasons such as dissension in description of aphasia and its symptoms, large number of test items which are not quite accurate, linguistic ambiguity and uncertainty as well as typical complexities of medical diagnosis cause accurate diagnosis of aphasia to be a particularly difficult and error prone medical task. To address the diagnosis of the four mentioned common types of Aphasia more efficiently, an adaptive Neuro-Fuzzy inference system (ANFIS) is proposed. This structure models the nonlinear relation between aphasia symptoms and resulting test scores as well as the degree of fuzzy belonging of the symptoms to all four major aphasia simultaneously. The proposed method in this paper is compared with a hierarchical fuzzy rule-based structure and a back propagating feed-forward neural network. Our method reaches to a maximum accuracy of 94.6% in 50 trials while the best result for other methods previously used is 91.6%. This method not only diagnoses the four types of Aphasia accurately, but also it is efficient for other medical diagnostic applications. © 2008 IEEE.

关键词： Fuzzy inference

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Type2 fuzzy set based automatic shadow region segmentation in intra vascular ultrasound images

Type2 fuzzy set based automatic shadow region segmentation i...

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2011 2nd IEEE International Conference on Signal and Image processing Applications, ICSIPA 2011

作者： Fathi-Azar, Elham Setarehdan, Seyed Kamaledin Control and Intelligent Processing Center of Excellence College of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9781457702419

This paper presents an automated algorithm for shadow regions detection in IVUS images using a histogram modification method for threshold selection. The method employs the Type2 Fuzzy Set together with spatial information for shadow region separation from the background image. Shadow regions usually occur behind the calcium deposits making it difficult or impossible to process tissue images in these regions. Results show that the proposed method is effective in detection of parts of the image in the shadow regions. Applying to a data set of 40 IVUS frames the results show a good agreement between the automatically detected and manually defined shadow regions boundaries by the proposed method and the expert, respectively. © 2011 IEEE.

关键词： Graphic methods

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