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Proceedings of the 2024 International Conference on Sports Technology and Performance Analysis

作者： Hui Li Qing Sun Xiao Zhang Bo Ceng Institute of Artificial Intelligence in Sports Capital University of Physical Education and Sports Beijing China Systems Engineering Institute Academy of Military Science Beijing China Beijing Institute of Precision Mechatronics and Controls Beijing China Innovation Center for Control Actuators Beiiing China

ISBN: (纸本)9798400712234

Exoskeletons have shown important application potential in assisting physical labor and reducing joint burden. As a typical task in physical labor, the research on the kinematic impact of handling is of great significance for the optimal design and practical application of exoskeleton. This study constructed three typical warehouse task scenarios—1.4 m handling, 1.8 m handling, and lifting—and analyzed the kinematic parameters, including joint angles and angular velocities, of eight male university students performing these tasks with and without exoskeleton, using a motion capture system. The results revealed that with exoskeleton significantly reduced the range of motion at the hip, elbow, and knee joints, and decreased the peak angular velocity of the elbow joint during the 1.8 m handling task and the peak angular velocity of the hip joint during the lifting task. However, no significant effects were observed on the mean angular velocities of the joints. These findings indicate that the passive exoskeleton limits the range of motion of the joint to a certain extent, but does not significantly affect the movement speed, and its adaptability in high dynamic tasks still needs to be improved. In the future, exoskeleton design should pay more attention to the adaptation of joint biomechanical properties, optimize flexibility and adaptability, and further evaluate the potential impact of long-term wear on joint health, so as to promote its promotion and development in practical application scenarios.

关键词： Joint angular velocity

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Finite-Time Attitude control for Coupled Spacecraft with Input Constraints

Finite-Time Attitude Control for Coupled Spacecraft with Inp...

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Chinese control Conference (CCC)

作者： Wanwan Zhu Yang Yukai School of Information and Control Engineering China University of Mining and Technology Xuzhou China Engineering Research Center of Intelligent Control for Underground Space Ministry of Education China University of Mining and Technology Xuzhou China Beijing Institute of Precision Mechatronics and Controls Beijing China Laboratory of Aerospace Servo Actuation and Transmission Beijing China

In this paper, a finite-time saturated attitude control algorithm is proposed for coupled spacecraft under flexible vibration, liquid sloshing, model uncertainty and external disturbance. By adding a feedback term, a saturated super-twisting sliding mode control algorithm is designed to realize coupled spacecraft attitude control in finite time. The main feature of the proposed control algorithm is that it is continuous and control torque to regulate the coupled spacecraft system affected by lumped uncertainty in finite time. Finally, the simulation results are given to verify the effectiveness of the proposed control algorithm.

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Experimental Study on Electrode Wear During the Edm of Microgrooves with Laminated Electrodes Consisting of Various Material Foils

SSRN

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SSRN 2023年

作者： Wu, Bo Wu, Huiyong Lei, Jianguo Shen, Haotian Xu, Bin Zhao, Hang Zhu, Likuan Wu, Xiaoyu Guangdong University Engineering Technology Research Center for Precision Components of Intelligent Terminal of Transportation Tools College of Urban Transportation and Logistics Shenzhen Technology University Guangdong Shenzhen518118 China Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control Engineering Shenzhen University Guangdong Shenzhen518060 China

Electrode wear during electrical discharge machining (EDM) is inevitable, and tool electrodes of different materials exhibit different wear rates. For a laminated electrode consisting of various material foils (LE-VMF), the components suffer from significantly different amounts of wear and also influencing each other, however, the form and cause of the wear are not clear. In this paper, the wear of electrode foils and their mutual influence during the EDM process using symmetric and asymmetric LE-VMFs were investigated through experiment. The wear forms of a single foil electrode and a foil of the same material in a LE-VMF were also compared. The experimental results show that copper foil with a lower wear rate had a protective effect on an adjacent brass foil with a larger wear rate in a LE-VMF, while the protective effect of the brass foil in a symmetric LE-VMF was larger than that in an asymmetric LE-VMF. In addition, when the thickness of the brass foil was greater than 150 μm, the working surface of the brass foil in the LE-VMF did not show any concavity-like wear in the middle of its thickness, as was the case for the single brass foil electrode. © 2023, The Authors. All rights reserved.

关键词： Wear of materials

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Predicted Generation of Micro-Structures in the Spray-Mist-Assisted Laser Machining of Cvd Diamond Surface

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SSRN 2022年

作者： Guo, Bing Zhang, Zhongbo Guo, Zhenfei Jia, Jianfei Meng, Qingyu Zhao, Qingliang Zeng, Zhaoqi Li, Kenan Xu, Lei Center for Precision Engineering School of Mechatronics Engineering Harbin Institute of Technology Harbin150001 China Beijing Institute of Control Engineering Beijing100094 China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasives & Grinding Co. Ltd Zhengzhou450001 China Beijing Spacecrafts Beijing100094 China

In this paper, a predicted ablation model in spray-mist-assisted laser machining was established for machining the micro-structured surface on chemical vapor deposition (CVD) diamond coating surface. Firstly, the principle of spray-mist-assisted laser machining was described, which points out that the machining method can effectively reduce the thermal effect and prevent the formation of recast layer compared with traditional laser machining. Then, the effects of water-assisted conditions on the laser machining were analyzed. After that, based on Gaussian optics and ablation threshold theory, the single groove ablation model was established. The effects of laser machining parameters included the laser power, the scanning speed and the defocusing quatity on the machining characteristics were discussed. And the correctness of the model was verified by the experiments. Finally, the parameter of scanning pitch was introduced when the raster scanning ablation experiment of surface structure was carried out. And the method of matrix convolution was used to solve the superposition problem of energy in different directions. © 2022, The Authors. All rights reserved.

关键词： Chemical vapor deposition

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Effects of strain paths on the fracture forming limit of high strength structural steel sheets

Effects of strain paths on the fracture forming limit of hig...

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2020 International Conference on Internet of Things, Artificial Intelligence and Mechanical Automation, IoTAIMA 2020

作者： Xu, Teng Xia, Qin-Xiang Qi, Zhen-Jie Wu, Xiao-Yu Ran, Jia-Qi Gong, Feng Guangdong Provincial Key Laboratory of Micro Nano Optomechatronics Engineering College of Mechatronics and Control Engineering Shenzhen University China Guangdong Provincial Key Laboratory of Precision Equipment and Manufacturing Technology School of Mechanical and Automotive Engineering South China University of Technology China Shenzhen Key Laboratory of Advanced Manufacturing Technology for MouldandDie College of Mechatronics and Control Engineering Shenzhen University China National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials China

The cruciform two-axial tensile specimen was designed and the two-axial tensile test scheme for different strain paths was developed. The effect of strain paths on the forming limit of high strength structural steel plates was obtained by the DIC method. The results show that for the unidirectional alternating loading test scheme, the equivalent strain of the ultimate strain is less than the sum of the equivalent strains from each step. When the main strain direction of the specimen pre-strain is perpendicular to the final strain path, the forming limit decreases with the increase of the pre-strain. © 2020 Published under licence by IOP Publishing Ltd.

关键词： Strain

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Ultra-precision cutting of linear micro-groove array for distributed feedback laser devices

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International Journal of Nanomanufacturing 2018年第1期14卷 9-22页

作者： Guo, Bing Yu, Xin Zeng, Zhaoqi Zhao, Qingliang Xu, Lei Liu, Xiaoliang Center of Precision Engineering School of Mechatronics Engineering Harbin Institute of Technology P.O. Box 413 Harbin150001 China Institute of Opto-Electronics School of Astraunutics Harbin Institute of Technology Harbin150080 China Institute of Opto-Electronics School of Astraunutics Harbin Institute of Technology Harbin150080 China Beijing Institute of Control Engineering Beijing100091 China Center of Precision Engineering School of Mechatronics Engineering Harbin Institute of Technology Harbin150001 China Beijing Spacecrafts Beijing100094 China Center of Precision Engineering School of Mechatronics Engineering Harbin Institute of Technology Harbin150001 China

The tunable range and beam linewidth of distributed feedback laser were determined by fabrication quality of the periodic linear micro-groove array on substrate, which grooves are high sloped and ranged sub-micron to few microns. Compared with the common micro-groove arrays (size from tens of microns to sub-millimetre), the ultra-precision cutting of these tiny and high-sloped linear micro-groove arrays are more difficult to realise. In this paper, a series of investigations was proposed for ultra-precision cutting of linear micro-groove array on polymethyl methacrylate (PMMA). Firstly, the different cutting processes included planing and fly-cutting were conducted. The workpiece morphology, surface quality and machining efficiency of these processes were investigated. Then, the fly cutting process was optimised by the calculation of non-free chip zone and the analysis of chip interference by cutting experiments. Finally, a novel tool positioning method based on acoustic emission was presented in order to realise high accuracy control of micro-groove arrays dimensions. Copyright © 2018 Inderscience Enterprises Ltd.

关键词： Morphology

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Analysis and optimization of microchannel array precision grinding processes with micro-structured micro-grinding tool

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Chinese Journal of Aeronautics 2025年第7期38卷

作者： Jianfei JIA Qinghe ZHANG Wei YANG Honghui YAO Guicheng WU Huan ZHAO Jianhui ZHU Kenan LI Bing GUO Jun QIN Zhengzhou Abrasive Grinding Research Institute Co. Ltd State Key Laboratory for High Performance Tools Zhengzhou 450001 China Center for Precision Engineering School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Zhongshan Sprecision Technology Co. Ltd Zhongshan 528437 China Sichuan Aerospace Fenghuo Servo Control Technology Co Ltd Chengdu 611130 China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China Shanxi Aerospace Qinghua Equipment Co. Ltd Changzhi 046012 China

Micro-grinding has been widely used in aerospace and other industry. However, the small diameter of the micro-grinding tool has limited its machining performance and efficiency. In order to solve the above problems, micro-structure has been applied on the micro-grinding tool. A morphology modeling has been established in this study to characterize the surface of micro-structured micro-grinding tool, and the grinding performance of micro-structured micro-grinding tool has been analyzed through undeformed chip thickness, abrasive edge width, and effective distance between abrasives. Then deviation analysis, path optimization and parameter optimization of microchannel array precision grinding have been finished to improve processing quality and efficiency, and the deflection angle has the most obvious effects on the rectangular slot depth, micro-structured micro-grinding tool could reduce 10% surface roughness and 20% grinding force compared to original micro-grinding tool. Finally, the microchannel array has been machined with a size deviation of 2 μm and surface roughness of 0.2 μm.

关键词： Grinding precision grinding Microchannel array Micro-structure Micro-grinding tool

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Effects of strain paths on the fracture forming limit of high strength structural steel sheets

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Journal of Physics: Conference Series 2020年第1期1605卷

作者： Teng Xu Qin-xiang Xia Zhen-jie Qi Xiao-yu Wu Jia-qi Ran Feng Gong Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control Engineering Shenzhen University Guangdong Provincial Key Laboratory of Precision Equipment and Manufacturing Technology School of Mechanical and Automotive Engineering South China University of Technology Shenzhen Key Laboratory of Advanced Manufacturing Technology for Mould&Die College of Mechatronics and Control Engineering Shenzhen University National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials

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A review and discussion of decomposition-based hybrid models for wind energy forecasting applications

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Applied Energy 2019年 235卷 939-953页

作者： Zheng Qian Yan Pei Hamidreza Zareipour Niya Chen School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing China Key Laboratory of Precision Opto-Mechatronics Technology Ministry of Education Beihang University Beijing China State Key Laboratory of Operation and Control of Renewable Energy & Storage Systems China Electric Power Research Institute Beijing 100192 China Department of Electrical and Computer Engineering University of Calgary Calgary Alberta Canada ABB Corporate Research Center Beijing China

With the continuous growth of wind power integration into the electrical grid, accurate wind power forecasting is an important component in management and operation of power systems. Given the challenging nature of wind power forecasting, various methods are presented in the literature to improve wind power forecasting accuracy. Among them, combining different techniques to construct hybrid models has been frequently reported in the literature. Decomposition-based models are a family of hybrid models that firstly decompose the wind speed/power time series into relatively more stationary subseries, and then build forecasting models for each subseries. In this paper, we present a comprehensive review of decomposition-based wind forecasting methods in order to explore their effectiveness. Decomposition-based hybrid forecasting models are classified into different groups based on the decomposition methods, such as, wavelet, empirical mode decomposition, seasonal adjust methods, variational mode decomposition, intrinsic time-scale decomposition, and bernaola galvan algorithm. We discuss decomposition methods in the context of alternative forecasting algorithms, and explore the challenges of each method. Comparative analysis of various decomposition-based models is also provided. We also explore current research activities and challenges, and identify potential directions for future research on this subject.

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An Improved Artificial Potential Field-based SImultaneous FORward Search (Improved APF-based SIFORS) method for robot path planning

An Improved Artificial Potential Field-based SImultaneous FO...

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International Conference on Ubiquitous Robots and Ambient Intelligence (URAI)

作者： Guanghui Li Shuiguang Tong Gang Lv Renyuan Xiao Feiyun Cong Zheming Tong Atsushi Yamashita Hajime Asama R&D Center of Mechatronics and Intelligent Control Zigong Innovation Center of Zhejiang University Zigong P. R. China School of Mechanical Engineering Zhejiang University Hangzhou P. R. China Department of Precision Engineering The University of Tokyo Tokyo Japan

An effective Improved Artificial Potential Field-based SImultaneous FORward Search (Improved APF-based SIFORS) method was developed in known environment, which was very similar with the path relaxation method. We firstly redefined potential functions to calculate a valid path, then proposed a SImultaneous FORward Search method (SIFORS method) to shorten the distance of planned path. Such path was calculated by connecting the sequential points produced by Improved APF method. And we mainly focused on discussing the Bidirectional Improved APF-based SIFORS method in this paper. The simulation results confirmed that our proposed path planning approach could calculate a shorter, collision-free, no oscillations and safe path to a destination than general Improved APF methods can, and consumed few computational times.

关键词： Force Path planning Robot kinematics Algorithm design and analysis Collision avoidance Relaxation methods

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