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International Symposium on Power Electronics, Electrical Drives, Automation and Motion, SPEEDAM

作者： J. M. Rosario L. K. Rincon D. Kubiak D. Dumur L. F. Melo UNICAMP - Laboratory of Automation and Robotics Camninas SP Brazil Department of Automatic Control Plateau du Moulon Gif-sur-Yvctte France UEL - State University of Londrina Londrina PR Brazil

CNC (Computer Numerical control) machine tools are devices of high precision milling largely employed due to their high precision and to allow simultaneous positioning and velocity control of each machine's axis. The main objective of this paper is to develop a virtual environment to realize a comparative study between two types of actuation systems (stepper motor and DC motor) focusing on implementation complexity and on the final result quality of each alternative.

关键词： DC motors Trajectory Computer numerical control Permanent magnet motors Machine tools Torque Fasteners

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Optimal Sensor Trajectories for Mobile Underwater Target Positioning with Noisy Range Measurements

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IFAC Proceedings Volumes 2014年第3期47卷 5139-5144页

作者： D. Moreno-Salinas A.M. Pascoal J. Aranda Department of Computer Science and Automatic Control National University Distance Education (UNED) Spain Laboratory of Robotics and Systems in Engineering and Science (LARSyS) Instituto Superior Tecnico (IST) University of Lisbon Portugal Adjunct Scientist National Institute of Oceanography (NIO) Goa India

There is considerable interest in reducing the number of sensors/beacons involved in underwater positioning/navigation systems since this has the potential to drastically reduce the costs and the time spent in deploying, calibrating, and recovering acoustic equipment at sea. Motivated by these considerations, we address the problem of single underwater target positioning based on acoustic range measurements between the target and a moving sensor at the sea surface. In particular, the goal of the present work is to compute optimal geometric trajectories for the surface sensor that will, in a well defined sense, maximize the range-related information available for underwater target positioning and tracking. To this effect, the Fisher Information Matrix and the maximization of its determinant are used to determine the sensor trajectory that yields the most accurate positioning of the target, while the latter describes a preplanned trajectory. It is shown that the optimal trajectory depends on the velocity of the sensor, the velocity and trajectory of the target, the sampling time between measurements, the measurement error model, and the number of measurements used to compute the FIM. Simulation examples illustrate the key results derived.

关键词： Autonomous underwater vehicles Fisher information matrix Cramer-Rao Bound optimization positioning single tracker

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Numerical analysis of residual stress effects on the stress field in a model of common carotid artery at wide range of transmural pressure

Numerical analysis of residual stress effects on the stress ...

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10th IASTED International Conference on Biomedical Engineering, BioMed 2013

作者： Piechna, Adam Cieslicki, Krzysztof Laboratory of Bioflows Institute of Automatic Control and Robotics Warsaw University of Technology Poland

ISBN: (纸本)9780889869530

The aim of this paper is to investigate the role of residual stresses in cerebral arteries, particularly in the Common Carotid Artery (CCA). Numerical simulations were based on experimental data described in the literature. Finite Element Method (FEM) was used, to calculate the stress response of the two-layer model of artery (intima-media and adventitia) to the transmural pressure. Strongly nonlinear stress-strain characteristics were applied. Conducted research showed the tendency and mechanisms connected with residual stress phenomenon. It was shown that residual stresses have strong impact on stress field for physiological and supraphysiological transmural pressures. Particularly, circumferential stress in the media layer was significantly reduced. We concluded that the presence of residual stress protects the intima-media layer against overstretching and rupture.

关键词： Residual stresses

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Multi-axis force sensing with pre-stressed resonant composite plates: An alternative to strain gauge force sensors

Multi-axis force sensing with pre-stressed resonant composit...

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IEEE/ASME (AIM) International Conference on Advanced Intelligent Mechatronics

作者： Davinson Castaño-cano Mathieu Grossard Arnaud Hubert Commissariat a l'energie atomique et aux energies alternatives Siege administratif Gif-sur-Yvette ÃŽle-de-France FR LIST Interactive Robotics Laboratory Gif-sur-Yvette France Automatic Control and Micro-Mechatronic Systems Department Université de Franche-Comté Besançon France

ISBN: (纸本)9781479957378

Industrial robots embedding multi-axis force sensors at the robot/environment interface presents numerous advantages in terms of safety, dexterity and collaborative perspectives. The key-point of these developments remains the availability of cheap but sufficiently precise multi-axis force sensors. This paper proposes a model-based approach to design a new alternative to commonly used strain gauge sensors. The principle of the device relies on pre-stress resonant composite plates where feedback control and measurement are achieved with piezoelectric transducers. The main originality of this work is that the force to be measured may present multi-axis components. Based on pre-stress and piezoelectric theories, a complete electromechanical model is proposed. This one is used during the design of a resonating composite Mindlin plate, embedding piezoelectric patches. It is shown that the effects of in-plane and out-of-plane external forces can be considered as pre-stress components. These ones, at the root of buckling phenomena, alter the stiffness of the structure and shift the plate resonance frequencies. Then, by solving the eigenvalue problem of the pre-stress vibrating structure, we can find the relationship between the natural frequencies of the structure and the externally applied multi-axis force. The proof of concept of this sensor is achieved on a case study. Finally, numerical results from both, home-made and commercial, finite element software demonstrates the interest of our approach to design integrated and inexpensive multi-axis force sensors solutions.

关键词： Force Strain Resonant frequency Force sensors Robot sensing systems Stress

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26th Annual Computational Neuroscience Meeting (CNS*2017): Part 3 Antwerp, Belgium. 15-20 July 2017 Abstracts

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BMC NEUROSCIENCE 2017年第SUPPL 1期18卷 95-176页

作者： [Anonymous] Department of Neuroscience Yale University New Haven CT 06520 USA Department Physiology & Pharmacology SUNY Downstate Brooklyn NY 11203 USA NYU School of Engineering 6 MetroTech Center Brooklyn NY 11201 USA Departament de Matemàtica Aplicada Universitat Politècnica de Catalunya Barcelona 08028 Spain Institut de Neurobiologie de la Méditerrannée (INMED) INSERM UMR901 Aix-Marseille Univ Marseille France Center of Neural Science New York University New York NY USA Aix-Marseille Univ INSERM INS Inst Neurosci Syst Marseille France Laboratoire de Physique Théorique et Modélisation CNRS UMR 8089 Université de Cergy-Pontoise 95300 Cergy-Pontoise Cedex France Department of Mathematics and Computer Science ENSAT Abdelmalek Essaadi’s University Tangier Morocco Laboratory of Natural Computation Department of Information and Electrical Engineering and Applied Mathematics University of Salerno 84084 Fisciano SA Italy Department of Medicine University of Salerno 84083 Lancusi SA Italy Dipartimento di Fisica Università degli Studi Aldo Moro Bari and INFN Sezione Di Bari Italy Data Analysis Department Ghent University Ghent Belgium Coma Science Group University of Liège Liège Belgium Cruces Hospital and Ikerbasque Research Center Bilbao Spain BIOtech Department of Industrial Engineering University of Trento and IRCS-PAT FBK 38010 Trento Italy Department of Data Analysis Ghent University Ghent 9000 Belgium The Wellcome Trust Centre for Neuroimaging University College London London WC1N 3BG UK Department of Electronic Engineering NED University of Engineering and Technology Karachi Pakistan Blue Brain Project École Polytechnique Fédérale de Lausanne Lausanne Switzerland Departement of Mathematics Swansea University Swansea Wales UK Laboratory for Topology and Neuroscience at the Brain Mind Institute École polytechnique fédérale de Lausanne Lausanne Switzerland Institute of Mathematics University of Aberdeen Aberdeen Scotland UK Department of Integrativ

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Robust trajectory tracking control of a quadrotor UAV

Robust trajectory tracking control of a quadrotor UAV

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International Conference on Systems and control (ICSC)

作者： Karima Benzaid Noura Mansouri Ouiddad Labbani-Igbida Laboratory of Automatic Control and Robotics Constantinel University Constantine Algeria Modeling Information & Systems lab. University of Picardie Jules Verne Amiens France

In this paper, we present two control strategies of a quadrotor Unmanned Aerial Vehicle (UAV). The dynamics of the system is controlled to achieve a complex trajectory tracking. A controller using the integral backstepping is developed for the stabilization of the six degrees of freedom (6DoF) of the system. Furthermore, we propose a hybrid strategy by combining the integral backstepping and the PID linear controller. For this, we divide the dynamic system into two subsystems; each one with 3DoF. For the stabilization of the rotational dynamics, the PID controller is proposed. The Integral Backstepping is applied for the longitudinal, lateral and vertical position stabilization. Finally, some numerical simulations are conducted to illustrate the robustness of both strategies.

关键词： Backstepping Trajectory Vehicle dynamics Mathematical model Algorithm design and analysis Rotors Lyapunov methods

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Stability of longitudinal bunch length feedback for heavy-ion synchrotrons

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Physical Review Special Topics - Accelerators and Beams 2013年第3期16卷 032801-032801页

作者： D. Lens H. Klingbeil Institute of Automatic Control Control Theory and Robotics Laboratory Technische Universität Darmstadt D-64283 Darmstadt Landgraf-Georg-Straße 4 Germany GSI Helmholtzzentrum für Schwerionenforschung GmbH D-64291 Darmstadt Planckstraße 1 Germany

In heavy-ion synchrotrons such as the SIS18 at Helmholtzzentrum für Schwerionenforschung, Helmholtz Centre for Heavy Ion Research (GSI), coherent oscillations of the particle bunches are damped by rf feedback systems to increase the stability and to improve the beam quality. In the longitudinal direction, important modes are the coherent longitudinal dipole and quadrupole oscillation. In this paper we present a new and rigorous approach to analyze the longitudinal feedback to damp these modes. The results are applied to the rf feedback loop at GSI that damps the quadrupole mode. The stability analysis is compared with simulations and is in good agreement with results of a beam experiment. Finally, we summarize practical implications for the operation of the feedback system regarding performance and stability.

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Underwater Target Positioning with a Single Acoustic Sensor

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IFAC Proceedings Volumes 2013年第33期46卷 233-238页

The availability of reliable underwater positioning systems to localize one or more vehicles simultaneously based on information received on-board a support ship or an autonomous surface vessel is key to the operation of some classes of AUVs. Furthermore, there is considerable interest in reducing the number of sensors involved in acoustic navigation/positioning systems to reduce the costs involved and the time consumed in the deployment, callibration, and recovery phases. Motivated by these considerations, in this paper we address the problem of single underwater target positioning based on measurements of the ranges between the target and a moving sensor at the sea surface, obtained via acoustic ranging devices. In particular, and speaking in loose terms, we are interested in determining the optimal geometric trajectory of the surface sensor that will, in a well defined sense, maximize the range-related information available for underwater target positioning. To this effect, an appropriate Fisher Information Matrix is defined and its determinant is maximized to yield the sensor trajectory that maximizes the accuracy of the target position estimate that can possibly be obtained with any unbiased estimator. It is shown that the optimal trajectory depends on the relative velocity of the sensor, the sampling time between measurements, and the number of measurements acquired for the FIM computation. Simulation examples illustrate the key results derived.

关键词： Autonomous Vehicles Underwater Navigation Optimal Sensor Placement Positioning Fisher Information Matrix Cramer-Rao Bound

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Simulation and experiment on automatic polarization alignment of fine polarization maintaining fibers

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Zhongguo Jiguang/Chinese Journal of Lasers 2013年第12期40卷

作者： Rong, Weibin Zhang, Wei Wang, Lefeng Cao, Yang Zhao, Lei Sun, Lining State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin Heilongjiang 150080 China AVIC Xi'an Fight Automatic Control Research Institute Xi'an Shaanxi 710065 China

To improve the performance of fine polarization maintaining fiber (PMF) couplers, it is necessary to increase the detection accuracy of polarization axis. The mathematical model of panda PMF index is established, and then the side view method is simulated. From the simulation results, the light is transmitted in the optical fiber and is focused on the other side, and the maximum light intensity of the fiber image is related to the rotation angle and the observation distance. When the observation distance is constant, the maximum value of light intensity changes periodically with the PMF rotation angle. When the observation plane is near the focused one of the transmitted light, the highest light intensity of optical image reaches the maximum value, which is the polarization axis detection parameter of PMF. Based on this, detection method which takes the maximum intensity as the feature is proposed. Combining the micro-vision technology, the polarization axis detection system for fine PMF is designed. The image sharpness function which can confirm the position of the detection plane is proposed. The experimental data are processed using the Fourier filtering method. By fitting the experiment data with the cubic spline method, the panda PMF polarization axis is determined. According to the experimental results, the repetitive detection error is 0.61°, which meets the requirements of PMF coupler manufacturing.

关键词： Polarization-maintaining fiber

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Robust free space detection in occupancy grid maps by methods of image analysis and dynamic B-spline contour tracking

Robust free space detection in occupancy grid maps by method...

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International Conference on Intelligent Transportation

作者： Matthias Schreier Volker Willert Institute of Automatic Control and Mechatronics Control Theory and Robotics Laboratory TU Darmstadt Germany

We propose a new method for free space detection and description for Advanced Driver Assistance Systems (ADAS) and autonomous vehicles. The detection is based on successive morphological image processing steps that are applied to an occupancy grid map-based environment representation acquired by an automotive radar sensor. The boundary of the found free space segment is traced and serves as a virtual measurement for a time-variant Kalman Filter in order to estimate and track the control points of a two-dimensional B-spline closed free space contour over time. In contrast to existing free space detection methods, the proposed solution incorporates knowledge about the vehicle's dimensions and does not exclude free space that is not directly in the line of sight, but mapped beforehand, as well as free space behind obstacles. Furthermore, the algorithm shows advantages in terms of an intuitive control over spatial and temporal smoothness of the solution as well as an inherent robustness due to model-based filtering. Moreover, the control points of the B-spline curve are proposed as a new low-dimensional representation of drivable free space of arbitrary shape. The effectiveness of the algorithm is demonstrated in real traffic scenarios.

关键词： Splines (mathematics) Vectors Aerospace electronics Space vehicles Image segmentation Approximation methods

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