检索结果-内蒙古大学图书馆

International Conference on Control, Automation and robotics (ICCAR)

作者： Hao Hong Minxiu Kong Jiawang Wang Qianjiang Wang School of Mechatronics Engineering Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin China

ISBN: (数字)9798350373172

ISBN: (纸本)9798350373189

In this paper, we research and analyse the practical needs of robotic arm to complete the complex path planning of robotic arm and smooth transition of multi-attitude in the shortest time under the premise of satisfying the dynamics constraints, and put forward the time-optimal trajectory planning based on NURBS curves and multi-attitude interpolation algorithm based on quaternion with NURBS curves. Using the complex nature of quaternions, the quaternions are converted into three-dimensional space points for curve interpolation, and finally converted back to quaternions to achieve the second-order continuity of multi-gesture interpolation; a time-optimal trajectory planning algorithm based on NURBS curves is designed, which discretises the curves, and fits the NURBS curves using the discrete points. At the same time, the optimal rate solution under all the constraints is calculated point by point according to the discrete points on the motion path, and the optimal velocity curve satisfying the dynamics constraints is obtained, so as to achieve the time-optimal trajectory planning. Finally, the feasibility of the designed trajectory planning algorithm is verified in the simulation software and experimental platform, and it is proved that the algorithm can effectively improve the running speed by at least 30%.

关键词： Surface reconstruction Interpolation Trajectory planning Service robots Quaternions Heuristic algorithms Software algorithms

来源：评论

学校读者我要写书评

暂无评论

Love Waves in a Piezoelectric Semiconductor Thin Film on an Elastic Dielectric Half-Space

引用

固体力学学报（英文版） 2023年第1期36卷 45-54页

作者： Ru Tian Guoquan Nie Jinxi Liu Ernian Pan Yuesheng Wang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China College of Engineering and Institute of Pioneer Semiconductor Innovation National Yang Ming Chiao Tung UniversityTaiwanChina Department of Mechanics Beijing Jiaotong UniversityBeijing 100044China

In this paper,Love waves propagating in a piezoelectric semiconductor(PSC)layered structure are investigated,where a PSC thin film is perfectly bonded on an elastic dielectric *** dispersion equations are derived *** influence of semiconducting properties on the propagation characteristics is examined in *** results show that the semiconducting effect reduces the propagation speed,and that the Love waves can propagate with a speed slightly higher than the shear wave speed of the elastic dielectric *** wave speed and attenuation significantly depend on the steady-state carrier density and the thickness of the PSC thin *** is also found that when the horizontal biasing electric field is larger than the critical value(corresponding to the zero attenuation),the wave amplitude is *** findings are useful for the analysis and design of various surface wave devices made of PSC.

关键词： Love wave Piezoelectric semiconductor Layered structure Dispersion Attenuation

来源：评论

学校读者我要写书评

暂无评论

A Self Bias-flip Piezoelectric Energy Harvester Array without External Energy Reservoirs achieving 488% Improvement with 4-Ratio Switched-PEH DC-DC Converter 44

A Self Bias-flip Piezoelectric Energy Harvester Array withou...

引用

44th Annual IEEE Custom Integrated Circuits Conference, CICC 2023

作者： Li, Zhen Chen, Zhiyuan Law, Man-Kay Du, Sijun Cheng, Xu Zeng, Xiaoyang Han, Jun Fudan University State Key Laboratory of Asic and System Shanghai China University of Macau State Key Laboratory of Analog and Mixed-Signal Vlsi China Delft University of Technology Department of Microelectronics Delft Netherlands

ISBN: (纸本)9798350399486

With the advent of the lnternet-of-Things (1oT) era, sensor nodes are required in almost all fields to achieve a better interaction between humans and the environment. Piezoelectric energy harvester (PEH), which exhibits an equivalent electrical model of an AC current source /P in parallel with the inherent capacitor CP, is a promising technology to resolve the energy problem of such sensor nodes. Recently, inductor-based rectifiers, capacitor-based rectifiers and hybrid rectifiers have been proposed to improve the energy extraction efficiency of PEH devices [1]-[5]. However, these structures all require the aid of additional capacitors or inductors to achieve bias-flip operation, as illustrated in Fig. 1. These extra passive devices are typically large, which can be a major bottleneck in system-volumeconstrained applications such as MEMS [4]. In response to the above problem, this work proposes a novel 8-phase self bias-flip PEH interface with charge recycling and reusing (SBFRR). By using the C P of 4 PEHs as flipping capacitors, this scheme achieves a high voltage flipping efficiency without using extra energy reservoirs. The 4 C P can also serve as flying capacitors to achieve switched-PEH DC-DC (SPDC) conversion for MPPT, while maintaining a MOPIR of >3.5× with a PEH input voltage (Vp) from 0. 78Vto4.9V. © 2023 IEEE.

关键词： Sensor nodes

来源：评论

学校读者我要写书评

暂无评论

A novel design of force-feedback master manipulator for remote ultrasound scanning

A novel design of force-feedback master manipulator for remo...

引用

2022 IEEE International Conference on robotics and Biomimetics, ROBIO 2022

作者： Li, Changle Zhang, Chentao Yu, Chuan You Zhang, Leifeng Liu, Gangfeng Zhao, Jie Harbin Institute of Technology State Key Laboratory of Robotics and System No.2 YiKuang Street NanGang District Harbin HeiLongJiang China

ISBN: (纸本)9781665481090

This paper presents a novel six-degree-of-freedom force feedback master manipulator for remote ultrasound scanning. Firstly, a new configuration based on a planar five-link mechanism is proposed, taking into account the practical needs of medical ultrasound scanning. This configuration has two operating modes and can provide three degrees of force feedback. Secondly, a hybrid force/position master-slave control system based on the kinetic model force feedback method is built, which can realize incremental master-slave control, variable proportional control, force feedback, and other functions. Finally, the positional accuracy, gravity balance effect, and force feedback performance of this master manipulator are verified through experiments. Experiments show that the average position error of this novel force feedback master manipulator is 1.18 mm, the average attitude error expressed in terms of Euler angles is 0.83°, and the maximum feedback force that can be provided is 12.1 N, which satisfies the requirements of ultrasonic scanning. © 2022 IEEE.

关键词： Feedback

来源：评论

学校读者我要写书评

暂无评论

Research on Surface Defect Detection Technology of Long-Distance and Long-Span FAST Cable

Research on Surface Defect Detection Technology of Long-Dist...

引用

Mechatronics and robotics Engineering (ICMRE), International Conference on

作者： Xin Tong Xuehe Zhang Gangfeng Liu Changle Li Jie Zhao State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

Aiming at the problems of large cable span, small number of defect samples and complex background environment in the FAST cable defect detection task, a set of real-time defect detection algorithms based on convolutional neural network is proposed to realize the accurate location and classification of defects. It can achieve a good detection effect for defects with multiple angles and sizes, especially suitable for medium and long distances. The algorithm is verified on the dataset, and its recognition accuracy can reach 91.7%. Equipped on the hardware inference platform, it fully meets the efficiency and accuracy requirements of FAST cable inspection site, can be used in actual cable quality inspection tasks, and can be widely promoted to real-time defect detection of various high-altitude hanging cables.

关键词： Mechatronics Simulation Inspection Real-time systems Inference algorithms Hardware Convolutional neural networks

来源：评论

学校读者我要写书评

暂无评论

A Contactless Magnetic Frequency-Boosting Mechanism for Wind Energy Harvesting

A Contactless Magnetic Frequency-Boosting Mechanism for Wind...

引用

Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS)

作者： Yunfei Li Manjuan Huang Tianyi Tang Heng Zhao Lining Sun Huicong Liu State Key Laboratory of Robotics and System Harbin Institute of Technology (HIT) CHINA School of Mechanical and Electric Engineering Jiangsu Provincial Key Laboratory of Advanced Robotics Soochow University CHINA

ISBN: (数字)9798350380200

ISBN: (纸本)9798350380217

This paper presents a non-contact magnetic frequency-boosting wind energy harvester suitable for low wind speed environments, designed to power various IoT sensors. The device comprises a driving component, a driven component, and a stator component. These components work together to convert low-speed rotational motion caused by wind into high-speed rotational motion, thereby achieving high-power electromagnetic energy output. Performance tests have shown that the output voltage increases with wind speed, reaching a peak voltage of 27V and a peak power of 1.6W at a wind speed of 10 m/s. The device has successfully powered LED bulbs and Bluetooth sensors, demonstrating its practicality for real-time environmental monitoring applications.

关键词： Temperature sensors Wind energy Wind speed Magnetic sensors Voltage Stators Sensor systems Environmental monitoring Electromagnetics Power generation

来源：评论

学校读者我要写书评

暂无评论

A Novel Approach for Solving Time-Varying Linear Equations and Its Application in Motion Tracking of Redundant Robots

A Novel Approach for Solving Time-Varying Linear Equations a...

引用

Frontiers of robotics and Software Engineering (FRSE), International Conference on

作者： Hong Yin Hongzhe Jin Jie Zhao State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

Solving time-varying linear equations is a common problem in many fields. In this article, a novel approach is proposed based on the cost function constructed by the mixed error, which is made up of the residual error and its integration. The merits of the novel approach include high accuracy, noise immunity, and asymptotic convergence. Since the derivative information of time-varying signals is used in the proposed method, a proportional-integral differentiator is designed based on the mixed estimation error for the first derivative estimation. The proposed differentiator has a high degree of precision, asymptotic convergence, and no chattering. In addition, theoretical analyses prove the convergence of the proposed optimal strategy and differentiator. Simulation results validate the effectiveness and superiority of the proposed strategy and the designed differentiator. Finally, the proposed approach is employed in the motion tracking of redundant robots.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Kinematic Decoupling Whole-body Control Method for a Mobile Humanoid Upper Body Robot

A Kinematic Decoupling Whole-body Control Method for a Mobil...

引用

Frontiers of robotics and Software Engineering (FRSE), International Conference on

作者： Fengjia Ju Hongzhe Jin Jie Zhao State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

The mobile humanoid upper body robot combines the humanoid upper body robot with the mobile platform. It has high redundancy and can complete complex tasks. However, coupling joints, including the waist joints and the mobile platform, exist in the configuration of the robot. During the task execution, the motion of the end-effectors on the dual arms are not independent, but interfere with each other through the motion of the waist and the mobile platform. Therefore, we need to decouple the waist and mobile platform from the dual arms. Based on the pseudo-inverse method of the redundant manipulators, we consider the motion of the coupling joints as a disturbance term and propose a kinematic decoupling whole-body control method. The method realizes the decoupling and cooperation of dual arms, avoids the interference of the inverse kinematics model of the dual arms, and fully releases the application potential of the high redundancy. The decoupling method allows the waist joints and the mobile platform to move randomly without affecting the task operation at the end-effectors, and to further plan their movements separately in order to smooth the whole body motion. The simulations on the mobile humanoid upper body robot verifies our method.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Data Augmentation for Improving CNNs in Medical Image Classification

Data Augmentation for Improving CNNs in Medical Image Classi...

引用

6th International Conference on Intelligent Computing and Signal Processing (ICSP)

作者： Yi Ren Zengmin He Yang Deng Bo Huang State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin China

Medical image is essential for physicians to diagnose diseases. And convolutional neural networks (CNNs) have gained momentum for computer-aided diagnosis (CAD) medical image. However, there are still challenges in CNNs related to a lack of data and class-imbalanced datasets. Data augmentation is utilized to address the issues mentioned above. In this study, the Pseudo-color enhancement algorithm (OCEAN and TWILIGHT), common linear transform, CLAHE enhancement, and K-means clustering algorithm were applied to pneumonia X-ray images for data augmentation. Thus, five processed datasets were finally obtained. The results indicated that five data-augmentation methods effectively improved the performance of CNNs for the pneumonia X-ray images binary classification detection, in which the CLAHE enhancement and OCEAN enhancement methods had the accuracy and F1 Score with 97.42%, 97.19%, and 97.42%, 98.36%, respectively. DenseNet121 showed the best classification performance of four CNNs utilized in this study, as evidenced by the area under the receiver operating characteristic (ROC) curves (AUC). To verify the generalizability of the two enhancement methods, CLAHE and OCEAN enhancement methods were applied to the Magnetic Resonance Imaging (MRI) dataset of Alzheimer's disease, which had the accuracy and F1 Score with 98.15% , 98.15%, and 97.22%, 97.68%, respectively. Therefore, these simple and efficient data-augmentation methods effectively improve the performance of CNNs for diagnosing medical image, which can provide theoretical reference for physicians to diagnose the above two diseases, and advance the application of clinical medicine.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Inertia Support Strategy for DC Collecting system of Wind Turbine Generator

Inertia Support Strategy for DC Collecting System of Wind Tu...

引用

2024 CPSS and IEEE International Symposium on Energy Storage and Conversion, CPSS and ISESC 2024

作者： Liu, Zenyang Sun, Kai Wang, Huan Lu, Junlong Tsinghua University State Key Laboratory of Power System Operation and Control Department of Electrical Engineering Beijing China Institute of Electrical Engineering Chinese Academy of Sciences Renewable Energy Power Generation System Research Department Beijing China

ISBN: (纸本)9798350380514

In wind turbine generators system, lacking of inertia is a common problem. In AC collecting system, some researches have been done to solve this problem. However, in DC collecting system, few researches were done. This paper analyzes the analogies between AC and DC collecting system and the virtual capacitor control corresponding to the virtual synchronous generator control. Small signal models of different precision are proposed considering the LLC resonant converter used for stepping-up. The virtual capacitance provided by the control is calculated using the small signal model and this verifies the effectiveness of the control quantitively and demonstrates that the small signal models are useful. © 2024 IEEE.

关键词： Wind Turbine Generators

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：