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China International Electrical and Energy Conference (CIEEC)

作者： Huidong Wang Jianhui Hu Yong Li Meng Zhao Department of Electrical Engineering Harbin Institute of Technology (HIT) Harbin China State Key Laboratory of Hydro-Power Equipment Harbin Electric Machinery Company Limited Harbin China

ISBN: (数字)9798350359558

ISBN: (纸本)9798350359565

Interturn short-circuit fault (ISCF) is a serious fault type in machine system. This paper proposes a novel Luenberger state observer (LSD) of short-circuit current using the xy subspace states for symmetrical six-phase permanent magnet synchronous machines (PMSMs). For six-phase control systems, the current symptoms in each subspace are affected by the ISCF. Compared to the dq subspace voltage equations, the xy subspace voltage equations are simpler. To reduce the complexity of the observer matrices, the short-circuit current observer is developed by the xy subspace states. Experimental results show the effectiveness of the proposed observer for different fault severities and operating conditions.

关键词： Permanent magnet machines Symmetric matrices Parameter estimation Short-circuit currents Observers Control systems Complexity theory

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Discovering Syntactic Interaction Clues for Human-Object Interaction Detection

Discovering Syntactic Interaction Clues for Human-Object Int...

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Conference on Computer Vision and Pattern Recognition (CVPR)

作者： Jinguo Luo Weihong Ren Weibo Jiang Xi'ai Chen Qiang Wang Zhi Han Honghai Liu Harbin Institute of Technology Shenzhen State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Institutes for Robotics and Intelligent Manufacturing Chinese Academy of Sciences Shenyang University

ISBN: (数字)9798350353006

ISBN: (纸本)9798350353013

Recently, Vision-Language Model (VLM) has greatly ad-vanced the Human-Object Interaction (HOI) detection. The existing VLM-based HOI detectors typically adopt a hand-crafted template (e.g., a photo of a person [action] a/an [object]) to acquire text knowledge through the VLM text encoder. However, such approaches, only encoding the action-specific text prompts in vocabulary level, may suffer from learning ambiguity without exploring the fine-grained clues from the perspective of interaction context. In this paper, we propose a novel method to discover Syntactic Interaction Clues for HOI detection (SICHOI) by using VLM. Specifically, we first investigate what are the essen-tial elements for an interaction context, and then establish a syntactic interaction bank from three levels: spatial relationship, action-oriented posture and situational condition. Further, to align visual features with the syntactic interaction bank, we adopt a multi-view extractor to jointly aggre-gate visual features from instance, interaction, and image levels accordingly. In addition, we also introduce a dual cross-attention decoder to perform context propagation be-tween text knowledge and visual features, thereby enhancing the HOI detection. Experimental results demonstrate that our proposed method achieves state-of-the-art performance on HICO-DET and V-COCO.

关键词： Visualization Vocabulary Computer vision Aggregates Detectors Syntactics Feature extraction

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Phase equilibria in Ni-Ti-Ta ternary system

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Transactions of Nonferrous Metals Society of China 2022年第4期32卷 1178-1187页

作者： Cui-ping WANG Peng YANG Yu-hui LIANG Shui-yuan YANG Jia-jia HAN Yong LU Xing-jun LIU Fujian Provincial Key Laboratory of Materials Genome College of MaterialsXiamen UniversityXiamen 361005China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen 518055China

Phase diagrams of two isothermal sections of the Ni-Ti-Ta ternary system at 1000 and 1200℃in a full composition range were determined by X-ray diffraction and electron probe *** experimental results indicated a ternary compoundτphase with low solid solubility and composition ranges of(16.3-22.4)at.%Ta,(15.9-24.1)at.%Ti and(58.5-60.0)at.%Ni at 1000℃.The two terminal solid solutions(bcc-(Ta)andβ-Ti)formed a continuous solid solution at 1000 and 1200℃.A certain amount of Ti can dissolve into Ni-Ta intermetallic compounds near the Ni-Ta side,with the highest value of 21.9 at.%observed in the Ni;Ta compound at 1000℃.

关键词： microstructure Ni-Ti-Ta ternary system isothermal section phase diagram electron probe microanalysis

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Moobot: a miniature origami omnidirectional jumping robot with high trajectory accuracy

TechRxiv

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TechRxiv 2022年

作者： Tang, Lingqi Li, Yao Li, Bing School of Mechanical Engineering and Automation Harbin Institute of Technology Shenzhen Shenzhen518055 China State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China

The jumping trajectory control is important for the jumping robots to overcome different obstacles. However, the trajectory control of a micro jumping robot is not easy. No insect-scale jumping robots have demonstrated the precise trajectory following yet. We proposed a miniature origami omnidirectional jumping robot (Moobot) that achieved the feedback control of jumping trajectory. The jumping of the robot is based on a four-bar origami structure and the SMA actuators. Unlike the tethered micro robots that powered externally, we integrated a miniature control board with LiPo battery on the robot for remote control. The overall system measured 6 g in mass, 5.5 cm in length and 2cm in height. Two strain gauges and an IMU sensor were used on the robot for the feedback control of the jumping force and take-off angle, respectively. Meanwhile, a reliable jumping mechanism and a novel supporting leg were designed to improve the jumping stability and trajectory accuracy. The standard deviation of the jumping distances was less than 1.4 cm, which is greatly improved from all previous micro jumping robots. Furthermore, we integrated the yaw control and conducted the omnidirectional jumping experiments. The results revealed that Moobot could climb different platforms from all directions precisely. © 2022, CC BY.

关键词： Feedback control

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Dynamic Visual SLAM Based on Semantic Information and Multi-View Geometry 5

Dynamic Visual SLAM Based on Semantic Information and Multi-...

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5th International Conference on Automation, Control and robotics Engineering, CACRE 2020

作者： Shi, Junyi Zha, Fusheng Guo, Wei Wang, Pengfei Li, Mantian Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin China

ISBN: (纸本)9781728198880

Visual Simultaneous Localization and Mapping (Visual SLAM) is considered to be one of the important foundations for mobile robots to move toward intelligence, which gives robots the ability to autonomously locate and construct maps in an unknown environment. In the past decades, great progress has been made in the field of visual SLAM, relatively mature algorithm system and program architecture are gradually developed. However, the current researches on visual SLAM mostly assume that the surrounding environment is static, which greatly limits the application of SLAM systems in real world. Aiming at the urgent need of mobile robots for precise localization and map construction in dynamic environment, methods are proposed in this paper. Image semantic segmentation based on deep learning and multi-view geometry methods are combined to recognize and segment moving objects. Only background features are used for camera tracking to avoid the impact of moving objects. Furthermore, an experimental platform is built using RGB-D camera and motion capture device, the effectiveness of the algorithm is verified by public datasets and real scene data. © 2020 IEEE.

关键词： Semantics

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Iterative learning control of trajectory tracking of robot manipulator based the SoC platform integrated motor drive and motion control 10

Iterative learning control of trajectory tracking of robot m...

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10th International Conference on Power Electronics, Machines and Drives, PEMD 2020

作者： Sun, Yongping Yang, Ming Chen, Yangyang Ni, Qinan Xu, Dianguo State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

ISBN: (纸本)9781839535635

With the development of SoC technology, the integration of FPGA+ARM has become the development direction of SoC. For the characteristics of integrated multi-axis motion control and motor drive, this paper selects Xilinx ZYNQ-7020 system-on-chip (SOC) with integrated dual-core ARM CPU and FPGA as the hardware platform control chip, an arm core motor drive algorithm. Another ARM core completes the interactive function and motion control, and the FPGA to complete the multi-axis hardware current loop and improve the system bandwidth. The iterative learning control (ILC) technology is widely used in robots to reduce the trajectory error of robots performing repetitive tasks. Using P-type iterative learning ILC combined with feedback control, which can compensate for nonrepeating disturbance. Finally, analysis of experimental results shows that iterative learning control combined with feedback control can significantly improve tracking accuracy. © PEMD *** right reserved.

关键词： Two term control systems

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Offline Deep Reinforcement Learning Two-stage Optimization Framework Applied to Recommendation systems

Offline Deep Reinforcement Learning Two-stage Optimization F...

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第43届中国控制会议

作者： Yihua Jiang Qi Liu Yanjie Li Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics and School of Mechanical Engineering and Automation the Harbin Institute of Technology

ISBN: (数字)9789887581581

ISBN: (纸本)9798350366907

Most traditional recommendation systems(RS) improve the model structure to obtain valid user behavior representation and make better recommendations. However, limited by the scale of the model, the model cannot accommodate an extended range of user historical data and cannot effectively extract long-term preferences. Reinforcement learning(RL) aims to maximize the cumulative return. Introducing RL can smoothly solve the long-term and short-term profit balance. However, there are specific problems with the direct combination of the two. Training RS that relies on offline user data will cause the strategy to suffer from an overestimation of action and distribution shift. Unlike the traditional RL environment, the ample space of the RS will also cause problems of insufficient exploration and sparse rewards, making the policy more difficult to learn. In response to the above issues, this work proposes an offline RL two-stage optimization framework. The framework consists of an offline RL method based on unknown behavior to alleviate the problem of action overestimation and a two-stage feature optimization training method to reduce the impact of large spaces. Experimental results prove that the method proposed in this article can effectively improve the long-term recommendation ability of the model and more effectively improve the model performance than the general offline RL algorithm.

关键词： Recommendation systems Overestimation of Actions Distribution Shift Deep Reinforcement Learning Two-stage Feature Optimization

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Semi-Autonomous Navigation Based on Local Semantic Map for Mobile Robot

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Journal of Shanghai Jiaotong university(Science) 2025年第1期30卷 27-33页

作者： ZHAO Yanfei XIAO Peng WANG Jingchuan GUO Rui Department of Automation Institute of Medical RoboticsShanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai200240China State Grid Intelligence Technology Co. Ltd.Jinan250013China

Mobile robots represented by smart wheelchairs can assist elderly people with mobility *** paper proposes a multi-mode semi-autonomous navigation system based on a local semantic map for mobile robots,which can assist users to implement accurate navigation(e.g.,docking)in the environment without prior *** order to overcome the problem of repeated oscillations during the docking of traditional local path planning algorithms,this paper adopts a mode-switching method and uses feedback control to perform docking when approaching semantic *** last,comparative experiments were carried out in the real *** show that our method is superior in terms of safety,comfort and docking accuracy.

关键词： semi-autonomous navigation mobile robot semantic map voice interaction

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Comparative study of voltage source inverter nonlinearity compensation using different signal information for table look up in PMSM drives 10

Comparative study of voltage source inverter nonlinearity co...

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10th International Conference on Power Electronics, Machines and Drives, PEMD 2020

作者： Long, Jiang Yang, Ming Chen, Yangyang Ni, Qinan Xu, Dianguo State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

ISBN: (纸本)9781839535635

The inverter nonlinearity compensation has been studied by the researchers widely, however, due to the poor polarity detection ability of the discrete control system and unavoidable noises from current feedback, unideal compensation happens when the motor speed is low and the load is small. In order to tackle with this problem. This paper presents an inverter nonlinearity compensation method in permanent magnet synchronous motor (PMSM) drives. The overall process is achieved by voltage signal injection, the only requirements are stator resistance and the maximum current of a given motor. The corresponding voltage errors are saved in look up table (LUT) and being used together with field-oriented control (FOC). In addition, a comparative study when using phase current feedback, phase current reference and phase voltage reference for compensation voltages look-up in the already established LUT is conducted. A 750-W voltage-source inverter PMSM drive controlled by the FOC algorithm is used for experiment verification, the results show that the phase current reference is the most proper signal for compensation voltages look-up, especially around the current zero-crossing condition. The comparative study in this paper can be easily applied in the real industrial application with no hardware introduction and very little algorithm change. © PEMD *** right reserved.

关键词： Table lookup

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Imitation of Manipulation Skills Using Multiple Geometries

arXiv

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arXiv 2022年

作者： Ti, Boyang Gao, Yongsheng Zhao, Jie Calinon, Sylvain State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin150001 China Idiap Research Institute MartignyCH-1920 Switzerland

Daily manipulation tasks are characterized by geometric primitives related to actions and object shapes. Such geometric descriptors are poorly represented by only using Cartesian coordinate systems. In this paper, we propose a learning approach to extract the optimal representation from a dictionary of coordinate systems to encode an observed movement/behavior. This is achieved by using an extension of Gaussian distributions on Riemannian manifolds, which is used to analyse a set of user demonstrations statistically, by considering multiple geometries as candidate representations of the task. We formulate the reproduction problem as a general optimal control problem based on an iterative linear quadratic regulator (iLQR), where the Gaussian distribution in the extracted coordinate systems are used to define the cost function. We apply our approach to object grasping and box opening tasks in simulation and on a 7-axis Franka Emika robot. The results show that the robot can exploit several geometries to execute the manipulation task and generalize it to new situations, by maintaining the invariant characteristics of the task in the coordinate system(s) of interest. Copyright © 2022, The Authors. All rights reserved.

关键词： Geometry

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