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European Control Conference (ECC)

作者： Victoria Erofeeva Oleg Granichin Olga Granichina Anton Proskurnikov Anna Sergeenko Skolkovo Institute of Science and Technology Moscow Russia (Faculty of Mathematics and Mechanics Science Educational Center "Mathematical Robotics and Artificial Intelligence") and With IPME RAS Saint Petersburg State University St. Petersburg Russia Herzen State Pedagogical University of Russia St. Petersburg Russia Politecnico di Torino Turin Italy IPME RAS St. Petersburg Russia

In this paper, a new algorithm for distributed multi-target tracking in a sensor network is proposed. The main feature of that algorithm, combining the SPSA techniques and iterative averaging ("consensus algorithm"), is the ability to solve distributed optimization problems in presence of signals with fully uncertain distribution; the only assumption is the signal’s boundedness. As an example, we consider the multi-target tracking problem, in which the unknown signals include measurement errors and unpredictable target’s maneuvers; statistical properties of these signals are unknown. A special choice of weights in the algorithm enables its application to targets exhibiting different behaviors. An explicit estimate of the residual’s covariance matrix is obtained, which may be considered as a performance index of the algorithm. Theoretical results are illustrated by numerical simulations.

关键词： Measurement errors Target tracking Perturbation methods Consensus algorithm Approximation algorithms Numerical simulation Planning

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Chattering-free fixed-time sliding mode control for bilateral teleoperation under unknown time-varying delay via disturbance and state observers

Advanced Control for Applications: Engineering and Industria...

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Advanced Control for Applications: Engineering and Industrial Systems 2020年第4期2卷

作者： Abadi, Ali Soltani Sharif Hosseinabadi, Pooyan Alinaghi Mekhilef, Saad Ordys, Andrzej Department of Electrical Engineering Faculty of Engineering Yazd University Yazd Iran Faculty of Engineering University of Malaya Kuala Lumpur Malaysia School of Software and Electrical Engineering Faculty of Science Engineering and Technology Swinburne University of Technology Melbourne Australia Center of Research Excellence in Renewable Energy and Power Systems King Abdulaziz University Jeddah Saudi Arabia The Institute of Automatic Control and Robotics Faculty of Mechatronics Warsaw University of Technology Warsaw Poland

This paper proposes a new chattering-free Fixed-time Observer-Based Sliding Mode Control (FOBSMC) scheme for synchronization of two bilateral teleoperations under unknown time-varying delay. The system is subjected to unknown disturbances which are estimated in a fixed time by utilizing the Disturbance Observer-based SMC scheme. The fixed-time State Observer-based SMC is designed to estimate the unmeasured velocity state, while the position state is assumed to be available. Fixed-time stability method is used to provide the system convergence time independently of initial states. A FOBSMC scheme is first designed for master system of bilateral teleoperation under unknown time-varying delay to track the environmental torque by the human operating torque in the presence of time delay in the communication channel, as well as estimating the unknown disturbances and unmeasured states. A FOBSMC scheme is designed to synchronize slave system to master system in the presence of time delay in the communication channel, as well as estimating disturbances and states. The stability analysis is performed for closed-loop system of combined controller-observer by using Lyapunov theory. The efficacy of the proposed method to fulfill a good transparency and stability under time-varying communication delays is tested by performing numerical simulation in Simulink/MATLAB. © 2020 John Wiley & Sons Ltd.

关键词： Time delay

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A Pencil Drawn Capacitive Sensor used for Liquid Drug Volume Measurement in Syringe Pump

A Pencil Drawn Capacitive Sensor used for Liquid Drug Volume...

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IEEE Applied Signal Processing Conference (ASPCON)

作者： Subir Das Badal Chakraborty School of Mechatronics and Robotics Indian Institute of Engineering Science & Technology Shibpur West Bengal India Faculty of Agricultural Engineering Bidhan Chandra Krishi Viswavidyalaya Kalyani West Bengal India

ISBN: (数字)9781728168821

ISBN: (纸本)9781728168838

In the field of medical applications, tracking and controlling of liquid drug delivery to the patient body is an important task at the critical stage of treatment. In this paper, a low cost, noninvasive continuous drug volume measurement in a syringe pump has been studied using a pencil-drawn capacitive (PDC) sensor. The drug volume variation inside the syringe injection pump has been measured using the fringing field capacitive method. In this preliminary investigation, the design optimization of the PDC sensor has been studied and observed its performance during the dispense of drugs through a syringe. Experimentally obtained the sensitivity, accuracy, and resolution of the sensor are 0.033pF/mm, ±0.2ml, and 0.1ml respectively.

关键词： Robot sensing systems Capacitors Signal processing Drugs Conferences Capacitive sensors Sensors

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Continuous-time fitted value iteration for robust policies

arXiv

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arXiv 2021年

作者： Lutter, Michael Belousov, Boris Mannor, Shie Fox, Dieter Garg, Animesh Peters, Jan Intelligent Autonomous Systems group Computer Science Department Technical University of Darmstadt Darmstadt Germany Andrew and Erna Viterbi Faculty of Electrical & Computer Engineering Technion – Israel Institute of Technology and a Distinguished Scientist at NVIDIA Tel Aviv Israel Allen School of Computer Science & Engineering University of Washington and Senior Director of Robotics Research NVIDIA Washington Seattle United States Computer Science Department University of Toronto NVIDIA Toronto Canada

Solving the Hamilton-Jacobi-Bellman equation is important in many domains including control, robotics and economics. Especially for continuous control, solving this differential equation and its extension the Hamilton-Jacobi-Isaacs equation, is important as it yields the optimal policy that achieves the maximum reward on a give task. In the case of the Hamilton-Jacobi-Isaacs equation, which includes an adversary controlling the environment and minimizing the reward, the obtained policy is also robust to perturbations of the dynamics. In this paper we propose continuous fitted value iteration (cFVI) and robust fitted value iteration (rFVI). These algorithms leverage the non-linear control-affine dynamics and separable state and action reward of many continuous control problems to derive the optimal policy and optimal adversary in closed form. This analytic expression simplifies the differential equations and enables us to solve for the optimal value function using value iteration for continuous actions and states as well as the adversarial case. Notably, the resulting algorithms do not require discretization of states or actions. We apply the resulting algorithms to the Furuta pendulum and cartpole. We show that both algorithms obtain the optimal policy. The robustness Sim2Real experiments on the physical systems show that the policies successfully achieve the task in the real-world. When changing the masses of the pendulum, we observe that robust value iteration is more robust compared to deep reinforcement learning algorithm and the non-robust version of the algorithm. Videos of the experiments are shown at https://***/view/rfvi Copyright © 2021, The Authors. All rights reserved.

关键词： Dynamic programming

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Study of 3D printing process: Optimization, quality analysis, and comparison of 3D printed and cast ceramic properties

Open Ceramics

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Open Ceramics 2025年 23卷

作者： Boleslavský, Adam Ovčačíková, Hana Mihola, Milan Mikkola, Aki Topinková, Michaela Bobovský, Zdenko VSB – Technical University of Ostrava Faculty of Mechanical Engineering Department of Robotics 17. listopadu 2172/15 Poruba Ostrava 708 00 Czech Republic Technical University of Ostrava Faculty of Materials Science and Technology Department of Thermal Engineering 17. listopadu 2172/15 Poruba Ostrava 708 00 Czech Republic Mechanical Engineering LUT School of Energy Systems Yliopistonkatu 34 Lappeenranta Finland

The goal of this study was to optimize and validate the procedures and methods used to form ceramic objects using 3D-print molding instead of cast molding. Chamotte refractory clay was shaped into 5 x 5 x 5 cm cubes using both the 3D-print-molding and cast-molding methods. These cubes were then evaluated, fired, and evaluated again. The 3D-print molding method used was an adaptation of ’direct ink writing’. Since refractory clay dries during manufacturing, a Photoneo 3D scanner was used to monitor cube shrinkage before firing. Other basic properties such as mineralogical composition, evaluated via X-ray diffraction, were also measured. X-ray fluorescence spectroscopy determined chemical composition. After firing, compressive strength, bulk density, porosity, and water absorption were measured and structural aspects such as cracking and porosity were evaluated. The 3D-print molding of the chamotte clay was largely successful. The measured compressive strength of the fired 3D-print-molded and cast-molded ceramic cubes was 31.4 MPa and 30.4 MPa, respectively. The 3D-print-molded ceramic parts were slightly more porous (14.5%) and absorptive (7.1%). Total volumetric shrinkage was 36 %. Detailed cross-sectional analysis of the samples identified defects related to specific shortcomings of both molding methods. This information suggests areas that could be targeted for refinement. Addressing them could lead to significant advancements, allowing 3D-print-molded ceramics and similar materials to achieve superior properties compared to conventional manufacturing methods. © 2025 The Authors

关键词： 3D printing methodology Additive manufacturing(AM) Ceramic Clay Direct ink writing (DIW)

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Determination of the Correlation between Process Parameters and Kerf Characteristics in Abrasive Waterjet Milling of High Strength 7075-T6 Aluminum Alloy

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Procedia Manufacturing 2020年 51卷 812-817页

作者： Panagiotis Karmiris-Obratański Rafał Kudelski Nikolaos E. Karkalos Angelos P. Markopoulos AGH University of Science and Technology Faculty of Mechanical Engineering and Robotics Department of Manufacturing Systems al. Mickiewicza 30 30-059 Cracow Poland National Technical University of Athens School of Mechanical Engineering Laboratory of Manufacturing Technology Heroon Polytechniou 9 15780 Athens Greece

Non-conventional manufacturing processes are often advantageous compared to conventional ones, as they can achieve high productivity in demanding cases. Abrasive waterjet (AWJ) machining is one of the most established non-conventional machining processes, which can achieve high material removal rates without leading to undesired workpiece material alterations and can render a large variety of shapes. In the present work, experiments regarding the AWJ milling of high strength 7075-T6 aluminum alloy are conducted with a view to correlate the process parameters, such as waterjet pressure, jet standoff distance, jet traverse speed and abrasive mass flow rate with depth of penetration, width and taper angle of the produced kerf. After the correlation between input and output parameters of the process is established, statistical analysis enables the determination of the influence of input parameters on output quantities and finally, appropriate process conditions for the regulation of depth of cut and kerf characteristics are derived.

关键词： Abrasive waterjet milling aluminum 7075-T6 depth of penetration kerf width kerf taper angle

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HPC-DMN integration at neural event boundary affects across-boundary BOLD representations and memory recollection

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NeuroImage 2025年 317卷

作者： Qiuyi Liu Siyang Li Lili Sun Zhipeng Li Peng Ren Wencai Ding Hongbo Bao Xia Liang School of Life Science and Technology HIT Faculty of Life Science and Medicine Harbin Institute of Technology Harbin 150001 China Research Center for Social Computing and Interactive Robotics Harbin Institute of Technology Harbin 150001 China Zhejiang Lab Hangzhou Zhejiang 311100 China Institute of Science and Technology for Brain-Inspired Intelligence and Department of Neurology Huashan Hospital Fudan University Shanghai 200433 China Department of Neurology The Second Affiliated Hospital of Wannan Medical College Wuhu 241002 China Department of Neurosurgery Harbin Medical University Cancer Hospital Harbin 150081 China Department of Neurosurgery Beijing Tiantan Hospital Capital Medical University Beijing 100070 China Frontiers Science Center for Matter Behave in Space Environment Harbin Institute of Technology Harbin 150001 China

Humans naturally divide their continuous experiences into discrete events, with event boundaries playing a critical role in this segmentation process. These boundaries are marked by significant shifts in brain activity, particularly in the hippocampal complex (HPC) and default mode network (DMN), which are key to learning and memory formation. We hypothesized that neural event boundaries in specific HPC-DMN regions contribute to episode recollection through across-boundary BOLD pattern shifts and neural event network formation, which may be influenced by two factors: network integration and boundary alignment. To test this, we used the widely recognized Sherlock fMRI dataset, which involves 22 human participants (17 subjects were used in this study). One key finding was that across-boundary BOLD pattern dissimilarity in the inferior parietal lobule (IPL) was greater for successfully recalled events compared to unsuccessful ones, specifically at boundaries with a high participation coefficient (indicative of high integration) or those aligned with the anterior superior temporal gyrus (aSTG) or the ventrolateral prefrontal cortex (vlPFC). Moreover, the entorhinal cortex played a crucial role in linking events into a network to facilitate subsequent recollection, particularly at boundaries with low participation coefficients or those aligned with the parahippocampus (PHC). These findings highlight the vital role of neural event boundaries in aiding comprehension and memory in naturalistic contexts through interactions with other brain regions.

关键词： fMRI Naturalistic Event boundary Hippocampus Default mode network

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Surface Topography of Ti 6Al 4V ELI after High Power EDM

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Procedia Manufacturing 2020年 47卷 788-794页

作者： Panagiotis Karmiris-Obratański Krzysztof Zagórski Jacek Cieślik Emmanouil Lazaros Papazoglou Angelos Markopoulos AGH University of Science and Technology Faculty of Mechanical Engineering and Robotics Department of Manufacturing Systems al. Mickiewicza 30 30-059 Cracow Poland National Technical University of Athens School of Mechanical Engineering Laboratory of Manufacturing Technology Heroon Polytechniou 9 15780 Athens Greece

Titanium alloys find extensive applications in the modern aerospace and offshore industry, as well in the field of biomedical implants. Nevertheless, the titanium inherent thermo-physical properties (low thermal conductivity and high chemical reactivity) make it a hard to machine material. For the efficient machining of titanium alloys, non-conventional machining processes are employed. Electrical Discharge Machining (EDM) is a non-contact machining process, in which the material removal occurs through repetitive electrical sparks. The capabilities of machining any electrically conductive material, regardless of its thermo-physical and other properties, render it as one of the most widely used non-conventional machining processes. As titanium alloys are used in high-quality parts and products, the integrity and texture of the machined surface constitute an essential parameter. The current study presents an experimental investigation of the surface texture and integrity of Ti6Al4V ELI after its machining with high power EDM. Namely, a full-scale experiment has been carried out, for pulse currents up to 65A and pulse-on time up to 200 μs, using graphite electrode. The surface texture (ST) and integrity has been estimated in terms of arithmetic mean height (Sa), the maximum height of scale-limited surface (Sz), maximum peak height (Sp), maximum pit height (Sv) and skewness of the scale-limited surface (Ssk). Additionally, through microscopy observation, the surface topography and integrity have been estimated, distinguishing and characterizing the surface cracks and micro-cracks. For all the above mentioned ST parameters, an Analysis of Variance (ANOVA) test has been performed.

关键词： Electrical Discharge Machining Titanium alloy Surface topography high power

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Associations of activity, sedentary, and sleep behaviors with cognitive and social-emotional health in early childhood

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Journal of activity, sedentary and sleep behaviors 2023年第1期2卷 7页

作者： Christine W St Laurent Charlotte Lund Rasmussen Jennifer F Holmes Amanda Cremone-Caira Laura B F Kurdziel Phillip C Desrochers Rebecca M C Spencer Department of Psychological and Brain Sciences University of Massachusetts Amherst 135 Hicks Way Tobin Hall Amherst MA 01003 USA. Department of Public Health and Nursing Norwegian University of Science and Technology Trondheim Norway. Department of Physical Education and Sport Sciences University of Limerick Limerick Ireland. Faculty of Physical Culture Palacký University Olomouc Olomouc Czech Republic. Department of Psychology Assumption College Worcester MA USA. Department of Psychology Merrimack College North Andover MA USA. Sensing Perception and Applied Robotics Division Charles River Analytics Cambridge MA USA. Institute for Applied Life Sciences University of Massachusetts Amherst Amherst MA USA.

Background:Early childhood is important for cognitive and social-emotional development, and a time in which to promote healthy movement behaviors (sedentary behavior, physical activity, and sleep). Movement behaviors may have interactive influences on cognition and social-emotional factors in young children, but most previous research has explored them independently. The purpose of this study was to determine if movement behaviors are associated with measures of cognitive and social-emotional health in young children and if so, to describe optimal compositions of movement behaviors of a daily cycle for such outcomes. Methods:Children (n = 388, 33 to 70 months, 44.6% female) from a clinical trial (*** ID: NCT03285880, first posted September 18, 2017) wore accelerometers on their wrists for 24-h for 9.56 ± 3.3 days. Movement behavior compositions consisted of time spent in sedentary behaviors, light intensity physical activity, moderate to vigorous intensity physical activity (MVPA), and sleep. Outcomes were cognitive (receptive vocabulary, declarative and procedural memory, and executive attention) and social-emotional measures (temperament and behavioral problems). Compositional linear regression models with isometric log ratios were used to investigate the relations between the movement behavior composition and the cognitive and social-emotional health measures. If a significant association was found between the composition and an outcome, we further explored the "optimal" 24-h time-use for said outcome. Results:Movement behavior compositions were associated with receptive vocabulary. The composition associated with the predicted top five percent of vocabulary scores consisted of 12.1 h of sleep, 4.7 h of sedentary time, 5.6 h of light physical activity, and 1.7 h of MVPA. Conclusions:While behavior compositions are related to vocabulary ability in early childhood, our findings align with the inconclusiveness of the current evidence regarding other d

关键词： Children Cognition Physical activity Sedentary behavior Sleep Social-emotional

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Sensor allocation in a forest fire monitoring system: A bi-objective approach

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AIP Conference Proceedings 2023年第1期2849卷

作者： Beatriz Flamia Azevedo Lino Costa Thadeu Brito José Lima Ana I. Pereira Research Centre in Digitalization and Intelligent Robotics (CeDRI) Instituto Politécnico de Bragança Braganca Portugal Algoritmi Research Centre University of Minho Braga Portugal Faculty of Engineering of University of Porto Porto Portugal INESC TEC—INESC Technology and Science Porto Portugal

Forests worldwide have been suffering from fires damages, provoking incalculable losses in fauna and flora, economic losses, people and animals’ deaths, among other problems. To avoid forest fires catastrophes, it is fundamental to develop innovative operations, such as a forest fire monitoring system. This work concentrates efforts on defining the optimum sensor allocation in a forest fires monitoring system based on a wireless sensor network. Thus, a bi-objective mathematical model is developed to solve the problem, in which the first objective consists of minimising the forest fire hazard of a given forest region, and the second objective refers to the sensors spreading into this region. The developed mathematical model was solved by genetic algorithm and the results demonstrated that the methodology was capable of presenting suitable solutions for the problem.

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