检索结果-内蒙古大学图书馆

IEEE International Conference on Mechatronics and Automation

作者： Xiulong Cui Jizhuang Fan Zhihui Dong Yue Ou Jie Zhao The State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

In this paper, we made an improved design on the traditional quadruped robot structure and developed a new small wheel-legged mobile robot structure. It has four legged configurations, which can be selected according to different situations, improving the mobility and operability of the robot. In wheeled mode, the robot can adjust its center of gravity according to actual needs. Including the rotational degree of freedom of the wheel, each leg has four degrees of freedom. Each leg adopts a series structure and moves the knee drive motor to the fuselage position using a parallel four-link mechanism and is symmetrically arranged with the hip drive motor. A wheel is installed at the end of the shank, and a DC brushless motor is built inside it, enabling the robot to have the function of wheeled motion. This article introduces the details of the wheel-legged robot, emphasizing the innovative design of the physical structure and the diversity of deformation. The forward kinematics was analyzed. Based on the full-elbow configuration (a type of legged configuration), a cycloidal motion optimization simulation was completed for the single leg structure. Simulation experiment has proven that the optimized robot’s single leg motion is smoother. Finally, we conducted a typical experiment using an embedded controller to control single leg motion. The experimental results verify that the optimized cycloidal motion of the robot meets the desired motion effect.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Effects of visual rotation axis and clockwise/counterclockwise directions on circular vection in virtual reality 24

Effects of visual rotation axis and clockwise/counterclockwi...

引用

2024 International Conference on Virtual Reality, Image and Signal Processing, ICVISP 2024

作者： Xu, Xiaotian Song, Zhe Zhang, Kexin Xu, Yan Zhang, Yuankun Fan, Xiaoya Pu, Fang Key Laboratory of Human Motion Analysis and Rehabilitation Technology of the Ministry of Civil Affairs Beihang University Beijing China Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province Dalian University of Technology Liaoning Dalian China State Key Laboratory of Virtual Reality Technology and System Beihang University Beijing China

ISBN: (纸本)9798400710926

Vection, an illusion of self-motion induced by visual stimulus frequently experienced in virtual reality, significantly impacts user experiences in gaming, driving simulation, and rehabilitation training. User often experience circular vection, an illusion of self-rotation. However, the effects of visual rotation axes and rotation directions on circular vection remain elusive. We employ a 3 (rotation axis: sagittal, coronal, vertical) × 2 (rotation direction: clockwise, counterclockwise) repeated-measures design. Twenty participants were recruited. They were exposed to a virtual visual rotating drum at 60 °/s to induce circular vection. The real-time estimation of perceived self-motion rotation velocity (PSRV) was obtained. Results indicated that during the 30-second constant rotation, the group-level PSRV showed an initial rapid increase followed by a slower rise. A significant interaction effect between rotation axis and direction was revealed. The rotation direction showed no significant effect on PSRV under sagittal and vertical conditions. However, under coronal condition, the PSRV was significantly higher when rotating counterclockwise, compared to rotation clockwise. In addition, when rotating counterclockwise, the highest PSRV appeared under sagittal condition, with the lowest under the coronal condition and the middle under the vertical condition. These findings provide valuable insights for designing VR scenarios with better user experience by vection manipulation. © 2024 Copyright held by the owner/author(s).

关键词： Virtual reality

来源：评论

学校读者我要写书评

暂无评论

An Effective Rotor-Shape Optimization Method for IPM Motor with 1/2 Slot per Phase per Pole

An Effective Rotor-Shape Optimization Method for IPM Motor w...

引用

International Conference on Applied Superconductivity and Electromagnetic Devices, ASEMD

作者： Guodong Yu Shuqi Sun Junlong Li Lijun Xiao Yongxiang Xu Jibin Zou State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

Although IPM motor with 1/2 slot per phase per pole has a relatively less rotor loss in comparison with other fractional slot concentrated winding (FSCW), the problems of THD of back-EMF and cogging torque are worse, which limits its application in electric vehicles and other industry fields. This paper proposes an effective rotor-shape optimization method to suppress both THD of back-EMF and cogging torque for improving torque ripple problem. Different from the prevalent rotor optimization methods, the proposed rotor-shape optimization method associates both shape function optimization of rotor surface with PM shaping, which can effectively decrease optimization parameters, and enhance optimization efficiency. To clarify the optimization strategy, the back-EMF and cogging torque for this PM motor with 1/2 slot per phase per pole are analyzed firstly. Then, the proposed optimization method is presented in detail. Finally, the optimized IPM motor is prototyped and its experimental results verifies the effectiveness of the proposed optimization method.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Sequential Design Framework of Robot Leg for High Locomotion Performance*

A Sequential Design Framework of Robot Leg for High Locomoti...

引用

IEEE International Conference on Cyborg and Bionic systems (CBS)

作者： Bin Qi Songyuan Zhang Yili Fu State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

Leg length, joint maximum torque/speed, motor model and transmission ratio are the most concerning parameters in the leg mechanism design of the legged-robot. The first two parameters are related to the locomotion performance, and the last two determine the actuator’s performance. At the beginning of the design, it is difficult to intuitively grasp the relationship between the leg length, the maximum torque of the joint and the locomotion performance of the legged-robot. When selecting the motor and determining the transmission ratio, these factors impact the control bandwidth and the locomotion performance. Considering the above-mentioned practical problems in the design, this paper proposes a systematic and two-stage sequential leg design framework for the legged-robot, which provides the design guidance in the early stage and the selection of the actuator motor and the determination of the transmission ratio in the later stage. Furthermore, the analytic solution of nonlinear constraint’s gradient was derived. Finally, a case study shows the application of the proposed framework. This work shows that finding an optimal set of design parameters among multiple objectives is not always possible. During design process, it is necessary to weigh the relationship between multiple indexes in many aspects.

关键词： Legged locomotion Actuators Torque systematics Process control Indexes Task analysis

来源：评论

学校读者我要写书评

暂无评论

Toward Earth system modeling with resolved clouds and ocean submesoscales on heterogeneous many-core HPCs

引用

National Science Review 2023年第6期10卷 153-167页

作者： Shaoqing Zhang Shiming Xu Haohuan Fu Lixin Wu Zhao Liu Yang Gao Chun Zhao Wubing Wan Lingfeng Wan Haitian Lu Chenling Li Yanfei Liu Xiaojing Lv Jiayu Xie Yangyang Yu Jun Gu Xuantong Wang Yan Zhang Chenhui Ning Yunlong Fei Xiuwen Guo Zhaoying Wang Xue Wang Zhenming Wang Binglin Qu Mingkui Li Haoran Zhao Yingjing Jiang Guang Yang Lv Lu Hong Wang Hong An Xin Zhang Yu Zhang Wentao Ma Fujiang Yu Jing Xu Xiaopei Lin Xueshun Shen Key Laboratory of Physical Oceanography Ministry of Education/Institute for Advanced Ocean Study/Frontiers Science Center for Deep Ocean Multispheres and Earth System (DOMES) College of Oceanic and Atmospheric Sciences Ocean University of China Laoshan Laboratory Ministry of Education Key Lab for Earth System Modeling and Department of Earth System Science Tsinghua University National Supercomputing Center in Wuxi Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of China School of Computer Science and Technology University of Science and Technology of China CEAKJ ADPRHexa Inc. National Marine Environmental Forecasting Center State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Ministry of Natural Resources Chinese Academy of Meteorological Sciences The Center of Earth System Modeling and Prediction China Meteorological Administration

With the aid of the newly developed 'Sunway' heterogeneous-architecture supercomputer,which has world-leading HPC(high-performance computer) capability,a series of high-resolution coupled Earth system models(SW-HRESMs) with up to 5 km of atmosphere and 3 km of ocean have been *** models can meet the needs of multiscale interaction studies with different computational *** we describe the progress of SW-HRESMs development,with an overview of the major advancements made by the international Earth science community in *** also show the preliminary results of SW-HRESMs with regard to capturing major weather-climate extremes in the atmosphere and ocean,stressing the importance of permitted clouds and ocean submesoscale eddies in modeling tropical cyclones and eddy-mean flow interactions,and paving the way for further model development to resolve finer scales with even higher resolution and more realistic ***,in addition to increasing model resolution,the development procedure for a non-hydrostatic cloud and ocean submesoscale resolved ESM is discusse d,laying out the major scientific directions of such a huge modeling advancement.

关键词： high-resolution Earth system models heterogeneous supercomputer cloud and submesoscale resolving weather-climate extremes finer cross-scale interactions

来源：评论

学校读者我要写书评

暂无评论

Acoustic propagation uncertainty in internal wave environments using an ocean-acoustic joint model

引用

Chinese Physics B 2023年第3期32卷 308-319页

作者：高飞徐芳华李整林秦继兴章沁雅 Department of Earth System Science Ministry of Education Key Laboratory of Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Naval Research Institute Tianjin 300061China School of Ocean Engineering and technology Sun Yat-Sen UniversityZhuhai 519000China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

An ocean-acoustic joint model is developed for research of acoustic propagation uncertainty in internal wave *** internal waves are numerically produced by tidal forcing over a continental slope using an ocean *** parameters(i.e.,internal wave,source depth,and water depth)contribute to the dynamic waveguide environments,and result in stochastic sound *** sensitivity of the transmission loss(TL)to environment parameters,statistical characteristics of the TL variation,and the associated physical mechanisms are investigated by the Sobol sensitivity analysis method,the Monte Carlo sampling,and the coupled normal mode theory,*** results show that the TL is most sensitive to the source depth in the near field,resulted from the initial amplitudes of higher-order modes;while in middle and far fields,the internal waves are responsible for more than 80%of the total acoustic propagation *** addition,the standard deviation of the TL in the near field and the shallow layer is smaller than those in the middle and far fields and the deep layer.

关键词： acoustic propagation uncertainty ocean-acoustic joint model internal wave sensitivity analysis

来源：评论

学校读者我要写书评

暂无评论

GCA-Net: A Global Context Aggregation Network for Effective Optical Flow

GCA-Net: A Global Context Aggregation Network for Effective ...

引用

Annual Conference of Industrial Electronics Society

作者： Tao Xie Jinghan Gao Ke Wang Ruifeng Li State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

Optical flow seeks to estimate the per-pixel 2D motion between two frames by identifying corresponding pixels. Current flow estimators typically involve per-pixel feature extraction, multi-scale 4D correlation volume construction, and iterative flow field updates through a Conv-GRU module. However, the locality of convolutional features in these methods renders the calculated correlations vulnerable to different noises. In addition, the Conv-GRU module of these methods is only executed with a convolution layer, which is incapable of exploiting context clues from larger window sizes even inside the image being queried itself, thus raising it more difficult for the model to process images with challenging regions, e.g., textureless areas. To this end, we introduce GCA-Net, a global context aggregation network for credible yet effective optical flow estimation. More specifically, we propose a highly efficient multi-scale transformer (MSFormer) layer which enables the per-pixel feature to aggregate long-range information from other features, hence building more accurate 4D correlation volumes. Besides, we develop an attention-enhanced Conv-GRU block (AttGRU) that can incorporate information alongside a larger context window even within itself empowering our network to estimate optical flow in even the most challenging regions. Experimentally, we demonstrate that GCA-Net outperforms previous state-of-the-art methods by large margins on Sintel (Final) and KITTI 2015 (background and foreground) benchmarks.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Poly-MOT: A Polyhedral Framework For 3D Multi-Object Tracking

Poly-MOT: A Polyhedral Framework For 3D Multi-Object Trackin...

引用

IEEE/RSJ International Conference on Intelligent Robots and systems (IROS)

作者： Xiaoyu Li Tao Xie Dedong Liu Jinghan Gao Kun Dai Zhiqiang Jiang Lijun Zhao Ke Wang State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

3D Multi-object tracking (MOT) empowers mobile robots to accomplish well-informed motion planning and navigation tasks by providing motion trajectories of surrounding objects. However, existing 3D MOT methods typically employ a single similarity metric and physical model to perform data association and state estimation for all objects. With large-scale modern datasets and real scenes, there are a variety of object categories that commonly exhibit distinctive geometric properties and motion patterns. In this way, such distinctions would enable various object categories to behave differently under the same standard, resulting in erroneous matches between trajectories and detections, and jeopardizing the reliability of downstream tasks (navigation, etc.). Towards this end, we propose Poly-MOT, an efficient 3D MOT method based on the Tracking-By-Detection framework that enables the tracker to choose the most appropriate tracking criteria for each object category. Specifically, Poly-MOT leverages different motion models for various object categories to characterize distinct types of motion accurately. We also introduce the constraint of the rigid structure of objects into a specific motion model to accurately describe the highly nonlinear motion of the object. Additionally, we introduce a two-stage data association strategy to ensure that objects can find the optimal similarity metric from three custom metrics for their categories and reduce missing matches. On the NuScenes dataset, our proposed method achieves state-of-the-art performance with 75.4% AMOTA. The code is available at https://***/lixiaoyu20001P0Iy-MOT.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Axial and radial electromagnetic-vibration characteristics of converter transformer windings under current harmonics

引用

High Voltage 2023年第3期8卷 477-491页

作者： Peiyu Jiang Zhanlong Zhang Zijian Dong Yu Yang Zhicheng Pan Jun Deng State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingShapingbaChina Maintenance&Test Centre EHVChina Southern Power GridGuangzhouGuangdongChina

The winding current harmonic content of converter transformer in operation is ***,affected by harmonics,the radial vibration characteristics are quite different from the power transformer,structural loosening and deformation caused by winding vibration are more ***,in view of the influence of current harmonics on axial and radial vibrations,this study builds a 3D winding electromagnetic vibration finite element simulation model,analyses the components and contents of current harmonics,compares the leakage flux and vibration distribution under the fundamental,harmonic and superimposed *** correlation relationship between the harmonic components and axial and radial vibration characteristics is obtained,and the vibration measurement test of±800 kV converter transformer in operation is carried out to verify the correctness of the analysis *** results show that the winding radial vibration amplitude will exceed the axial vibration affected by *** importantly,under the superposition of the fundamental,5th and 7th harmonic current,the vibration contribution of the converter transformer tank is mainly radial vibration,and the vibration dominant frequency is shifted from 100 Hz under the fundamental current to 400 Hz.

关键词： winding harmonics harmonic

来源：评论

学校读者我要写书评

暂无评论

Indoor Confined Space: GNSS Multi-Frequency Location Method based on Pursuit Principle 14

Indoor Confined Space: GNSS Multi-Frequency Location Method ...

引用

14th International Conference on Indoor Positioning and Indoor Navigation - Work-in Progress Papers, IPIN-WiP 2024

作者： Heng, Zhang Qing, Wang Lu, Huang Yaning, Li Jianqiang, Cheng Shiyuan, Liu The 54th Research Institute of China Electronics Technology Group Corporation China State Key Laboratory of Satellite Navigation System and Equipment Technology China

Aiming at the problem that it is difficult to carry out effective high-precision positioning in the complex and limited indoor space environment, this paper proposes an indoor limited space GNSS multi-frequency PSO (Particle Swarm Optimization) positioning method. This algorithm effectively solves the positioning technical problems which caused by inaccurate indoor spatial signal ranging. further we analyze the factors that affect the performance of the positioning algorithm. Compared to our team's existing KPI-based doppler positioning algorithm, the algorithm in this paper improves the problem of inaccurate range measurement, which caused by frequent cycle slips of signal loss. Through multi-frequency coordination and local optimization processing, the stability and continuity of indoor high-precision positioning are improved. The simulation results of semi-measured data show that the accuracy of the positioning algorithm in this paper is equivalent to that of the existing algorithm. When some signals are temporarily lost and refilled, the performance of this algorithm is better than that of the existing algorithm, and it has better continuity and robustness. © 2024 Copyright for this paper by its authors.

关键词： Particle swarm optimization (PSO)

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：