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Analysis and Control of Novel Deflection-Type PM Multi-DOF Actuator 被引量:3
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作者 Zheng Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第2期99-105,共7页
This paper mainly presents a PM multi-DOF actuator for robot in-wheels drive applications and its control method. The torque model is established based on the finite-element model of the single pair poles in 3D finite... This paper mainly presents a PM multi-DOF actuator for robot in-wheels drive applications and its control method. The torque model is established based on the finite-element model of the single pair poles in 3D finite element method software. Due to the special structure of the actuator,the Euler angles are adopted for deriving the kinematics and dynamic model. To reduce the effects of uncertainties of modeling error,nonlinear friction and external disturbances in the system,an approximation of neural network adaptive control method is applied to the actuator. The computation and simulation results show that the proposed analysis and control method can effectively derive the characteristics and improve the motion performance,which provides the primary theoretical guide for the configuration design,optimization and control research of multi-DOF deflection type actuators. 展开更多
关键词 deflection-type multi-dof PM actuator neural network control
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FLEXIBLE 2-DOF STEERING MODEL OF MULTI-AXLE HEAVY-DUTY VEHICLE 被引量:1
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作者 YangBo WangXuelin HuYujin LiChenggang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期618-622,共5页
A flexible two degrees of freedom (2-DOF) steering model of multi-axlevehicle (MAV) is presented with considering the effect of frame flexibility based on the classic2-DOF model. A method to calculate the frame flexib... A flexible two degrees of freedom (2-DOF) steering model of multi-axlevehicle (MAV) is presented with considering the effect of frame flexibility based on the classic2-DOF model. A method to calculate the frame flexibility is derived by using three moments equation.The steering stability of MAV is analyzed. The steering performance of MAV is also researched infrequency domain. Simulation results show that the dynamic effects of flexible model are more severethan rigid model and the flexible effect of frame will weaken the steering stability of MAV.Different disposals of steering axles lead to different steering characteristics of MAV. Thein-phase steering mode improves the steering characteristics and stability at high speed. Theanti-phase steering mode increases the steering mobility at low vehicle speed. 展开更多
关键词 multi-axle vehicle 2-dof model Steering characteristic Frame flexibility
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沙利度胺叠加DOF方案治疗Ⅳ期胃癌患者的效果及对血清sVEGFR-1、TGF-β1表达的作用
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作者 杨彦冰 《中国医学创新》 CAS 2023年第24期77-80,共4页
目的:研究沙利度胺叠加DOF方案(多西他赛+奥沙利铂+氟尿嘧啶)治疗Ⅳ期胃癌患者的效果及对血清可溶性血管内皮生长因子受体-1(sVEGFR-1)、转化生长因子-β_(1)(TGF-β_(1))表达的作用。方法:选择丹东市第一医院2018年3月—2020年3月收治... 目的:研究沙利度胺叠加DOF方案(多西他赛+奥沙利铂+氟尿嘧啶)治疗Ⅳ期胃癌患者的效果及对血清可溶性血管内皮生长因子受体-1(sVEGFR-1)、转化生长因子-β_(1)(TGF-β_(1))表达的作用。方法:选择丹东市第一医院2018年3月—2020年3月收治的87例Ⅳ期胃癌患者。以入院单双号的差异将所有患者分为叠加组(43例)及对照组(44例)。对照组开展DOF方案治疗,叠加组则开展沙利度胺叠加DOF方案治疗。分析两组临床疗效,治疗前后血清sVEGFR-1、TGF-β_(1)表达,不良反应,生活质量。结果:在临床总有效率方面对比,叠加组高于对照组(P<0.05);治疗2个疗程后,叠加组血清sVEGFR-1表达水平相较于对照组更高(P<0.05),而TGF-β_(1)表达水平相较于对照组更低(P<0.05);在不良反应总发生率方面对比,两组差异无统计学意义(P>0.05);治疗2个疗程后,两组生活质量综合评定问卷-74(GQOLI-74)评分相较于本组治疗前均更高(P<0.05),且叠加组高于对照组(P<0.05)。结论:沙利度胺叠加DOF方案应用于Ⅳ期胃癌患者的疗效显著,且能改善血清sVEGFR-1、TGF-β_(1)表达,不增加不良反应,提升生活质量。 展开更多
关键词 Ⅳ期胃癌 沙利度胺 dof 方案 可溶性血管内皮生长因子受体-1 转化生长因子-β_(1)
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Development of Five-Finger Multi-DoF Myoelectric Hands with a Power Allocation Mechanism
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作者 Tatsuya Seki Tatsuhiro Nakamura Ryu Kato Soichiro Morishita Hiroshi Yokoi 《Journal of Mechanics Engineering and Automation》 2014年第2期97-105,共9页
关键词 分配机制 多自由度 肌电 功率 手指 机器人手 冗余自由度 轻量化
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Flexible Bio-tensegrity Manipulator with Multi-degree of Freedom and Variable Structure 被引量:8
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作者 Dunwen Wei Tao Gao +2 位作者 Xiaojuan Mo Ruru Xi Cong Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第1期83-93,共11页
Conventional manipulators with rigid structures and sti ness actuators have poor flexibility,limited obstacle avoidance capability,and constrained workspace.Some developed flexible or soft manipulators in recent years... Conventional manipulators with rigid structures and sti ness actuators have poor flexibility,limited obstacle avoidance capability,and constrained workspace.Some developed flexible or soft manipulators in recent years have the characteristics of infinite degrees of freedom,high flexibility,environmental adaptability,and extended manipulation capability.However,these existing manipulators still cannot achieve the shrinking motion and independent control of specified segments like the animals,which hinders their applications.In this paper,a flexible bio-tensegrity manipulator,inspired by the longitudinal and transversal muscles of octopus tentacles,was proposed to mimic the shrinking behavior and achieve the variable motion patterns of each segment.Such proposed manipulator uses the elastic spring as the backbone,which is driven by four cables and has one variable structure mechanism in each segment to achieve the independent control of each segment.The variable structure mechanism innovatively contains seven lock-release states to independently control the bending and shrinking motion of each segment.After the kinematic modeling and analysis,one prototype of such bionic flexible manipulator was built and the open-loop control method was proposed.Some proof-of-concept experiments,including the shrinking motion,bending motion,and variable structure motion,were carried out by controlling the length of four cables and changing the lock-release states of the variable structure mechanism,which validate the feasibility and validity of our proposed prototype.Meanwhile,the experimental results show the flexible manipulator can accomplish the bending and shrinking motion with the relative error less than 6.8%through the simple independent control of each segment using the variable structure mechanism.This proposed manipulator has the features of controllable degree-of-freedom in each segment,which extend their environmental adaptability,and manipulation capability. 展开更多
关键词 Bio-tensegrity CABLE-DRIVEN actuation multi-degree-of-freedom(multi-dof) FLEXIBLE MANIPULATOR Variable structure mechanism
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Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV 被引量:3
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作者 ZHANG Ming-jun , ZHENG Jin-xing , ZHANG Jing College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001 ,China College of Computer and Information Science, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2002年第1期81-86,共6页
To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an o... To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an object. A changingweight vtlue method is put forward and a selection formula is modified. Some experiments were implemented on an AUV.TwinBurger. The results shows that this method is effective and feasible. 展开更多
关键词 AUV multi - objective optimization GENETIC algorithm SELECTION method
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:12
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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沙利度胺联合DOF方案治疗晚期胃癌的效果及对血清可溶性血管内皮生长因子受体-1表达的影响 被引量:1
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作者 杜娟 公小蕾 《中国处方药》 2021年第2期98-100,共3页
目的探讨沙利度胺联合DOF方案治疗晚期胃癌的效果及对血清可溶性血管内皮生长因子受体-1表达的影响。方法将2016年1月~2018年12月收治的126例晚期胃癌患者纳入本研究,随机分为DOF化疗组和沙利度胺联合DOF化疗组,每组63例,DOF化疗组患者... 目的探讨沙利度胺联合DOF方案治疗晚期胃癌的效果及对血清可溶性血管内皮生长因子受体-1表达的影响。方法将2016年1月~2018年12月收治的126例晚期胃癌患者纳入本研究,随机分为DOF化疗组和沙利度胺联合DOF化疗组,每组63例,DOF化疗组患者给予DOF方案治疗,沙利度胺联合DOF化疗组患者给予沙利度胺联合DOF方案治疗,21 d为1个周期,两组均连续治疗2个周期。比较两组患者的治疗效果及不良反应,并采用酶联免疫吸附(ELISA)法检测化疗前后两组患者血清中sVEGFR-1的表达水平。结果化疗2个周期后评价疗效,结果发现沙利度胺联合DOF化疗组RR(63.49%)明显高于DOF化疗组RR(50.79%),差异有统计学意义(P<0.05)。两组患者均完成2个周期诱导化疗,均未出现Ⅳ级不良反应。沙利度胺联合DOF化疗组患者的恶心呕吐及腹泻的发生率明显低于DOF化疗组(P<0.05),但便秘的发生率明显高于DOF化疗组(P<0.05),两组患者其他不良反应的发生率之间无显著性差异(P>0.05)。化疗前两组患者的血清sVEGFR-1表达水平相比无明显差异(P>0.05),化疗后DOF化疗组患者的血清sVEGFR-1表达水平较化疗前无明显差异(P>0.05),化疗后沙利度胺联合DOF化疗组患者的血清sVEGFR-1表达水平较化疗前明显上升(P<0.05),并显著高于DOF化疗组(P<0.05)。结论沙利度胺联合DOF方案治疗晚期胃癌的有效率较高,不良反应易于耐受,有可能是通过上调血清sVEGFR-1表达水平,进而抑制肿瘤血管生成。 展开更多
关键词 胃癌 dof方案 沙利度胺 可溶性血管内皮生长因子受体-1
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow spindle FANCY YAM SPINNING machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 multi - bar WARP KNITTED fabric computer -aided PATTERN design PATTERN Object Windows class Library (OWL) programming.
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APPLICATION OF FRF ESTIMATOR BASED ON ERRORS-IN-VARIABLES MODEL IN MULTI-INPUT MULTI-OUTPUT VIBRATION CONTROL SYSTEM
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作者 GUAN Guangfeng CONG Dacheng HAN Junwei LI Hongren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第4期101-105,共5页
The FRF estimator based on the errors-in-variables (EV) model of multi-input multi-output (MIMO) system is presented to reduce the bias error of FRF HI estimator. The FRF HI estimator is influenced by the noises i... The FRF estimator based on the errors-in-variables (EV) model of multi-input multi-output (MIMO) system is presented to reduce the bias error of FRF HI estimator. The FRF HI estimator is influenced by the noises in the inputs of the system and generates an under-estimation of the true FRF. The FRF estimator based on the EV model takes into account the errors in both the inputs and outputs of the system and would lead to more accurate FRF estimation. The FRF estimator based on the EV model is applied to the waveform replication on the 6-DOF (degree-of-freedom) hydraulic vibration table. The result shows that it is favorable to improve the control precision of the MIMO vibration control system. 展开更多
关键词 multi-input multi-output(MIMO) system Errors-in-variables(EV) model 6-dof hydraulic vibration table Waveform replication
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球形电动机及其研究发展综述
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作者 赵静 何威 +3 位作者 刘向东 李伟力 李争 杨磊 《中国电机工程学报》 EI CSCD 北大核心 2024年第2期737-754,I0026,共19页
球形电动机是一种具有球体结构的新型电动机,可单机实现在三维空间内的多自由度运动,且适合应用于人工智能及姿态控制系统动量球等相关领域,得到了各国学者的广泛关注与研究。球形电动机拓展了转子运动范围,是电动机行业未来的一个重要... 球形电动机是一种具有球体结构的新型电动机,可单机实现在三维空间内的多自由度运动,且适合应用于人工智能及姿态控制系统动量球等相关领域,得到了各国学者的广泛关注与研究。球形电动机拓展了转子运动范围,是电动机行业未来的一个重要发展方向。与传统单自由度电动机相比,球形电动机结构较为复杂,且运动模式较为特殊,因此,对球形电动机的分析研究有别于传统单自由度电动机。该文整理各国学者对球形电动机的研究工作,总结归纳球形电动机的概念及发展历程,对比研究球形电动机不同的工作原理、拓扑结构及设计优化方法,探讨球形电动机的性能、转子位置检测方法、控制方法、转子支撑方式、应用场合及关键技术,最后总结球形电动机的未来发展趋势。 展开更多
关键词 球形电动机 多自由度运动 拓扑结构 设计优化方法 控制技术
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多自由度振荡浮子装置波浪爬升特性试验与数值模拟
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作者 于通顺 陈星羽 +3 位作者 唐渔滢 宋昊阳 梅淙堡 黄淑亭 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第2期201-208,共8页
增加振荡浮子式波浪能发电装置的自由度可以拓宽设备的捕获频带,从而有效地提高其捕获效率,但这也意味着浮子与波浪间的作用过程更加复杂,产生的波浪爬升等非线性现象不容忽视,严重时甚至会发生越浪从而降低浮子装置的使用寿命和效率.... 增加振荡浮子式波浪能发电装置的自由度可以拓宽设备的捕获频带,从而有效地提高其捕获效率,但这也意味着浮子与波浪间的作用过程更加复杂,产生的波浪爬升等非线性现象不容忽视,严重时甚至会发生越浪从而降低浮子装置的使用寿命和效率.本文开展了规则波作用下多自由度浮子迎浪侧波浪爬升特性的物理模型试验,对单自由度运动和多自由度耦合运动的浮子上的波浪爬高进行了比较,以分析在有无动力输出装置(power take-off,PTO)阻尼条件下自由度之间的相互作用效应,并使用数值模拟分析耦合运动浮子周围的流场分布.结果显示,增加自由度可以导致没有PTO阻尼的浮子上的波浪爬高显著降低,有效降低越浪风险.对于有PTO阻尼的多自由度振荡浮子,增加垂荡方向上的PTO阻尼力对波浪爬升有很大影响.三自由度耦合运动浮子能更好地利用波浪能并具有更好的安全性. 展开更多
关键词 波浪能 振荡浮子 多自由度 波浪爬升
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基于多源异构信息融合的采摘机械臂驱动控制研究
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作者 宋秦中 胡华亮 《山西农业大学学报(自然科学版)》 CAS 北大核心 2024年第1期111-119,共9页
[目的]为了准确感知采摘机械臂的作业信息,提高驱动控制精度,需要对多自由度采摘机械臂的驱动控制模块进行优化设计。[方法]本研究将采摘机械臂各关节自由度、运动学以及动力学原理融合到设备结构中,完成了多自由度采摘机械臂等效模型... [目的]为了准确感知采摘机械臂的作业信息,提高驱动控制精度,需要对多自由度采摘机械臂的驱动控制模块进行优化设计。[方法]本研究将采摘机械臂各关节自由度、运动学以及动力学原理融合到设备结构中,完成了多自由度采摘机械臂等效模型的构建。基于构建的等效模型,确定多源传感器设备的安装位置,利用内部安装的传感器设备对机械臂的实时运行信息进行采集,获取位姿信息。同时,根据传感器的空间位置及其相互之间的作用进行信息分群,得出信息级融合结果,以此作为特征级信息融合结果的输入值,提取多源异构信息特征,并通过特征匹配完成融合操作,由此得出任意时刻采摘机械臂运行参数的检测结果。[结果]结合给定的采摘任务,计算采摘机械臂所需的驱动动力以及位姿数据,通过与当前数据的比对确定驱动控制量,利用装设的驱动控制器生成可执行的控制指令,完成驱动控制。与2种对照方法进行的对比试验显示,基于多源异构信息融合的驱动控制方法采摘机械臂的位置控制误差降低约25 mm,姿态角与驱动力控制误差分别降低了0.22°和6.32 mm,得出的控制数据更精准。[结论]由于多源异构信息融合技术能够发挥多种数据的优势,获取到更全面、更准确的位姿信息和控制数据,能够实现对目标果实的精准采摘,从而降低了采摘工作对果实的伤害,具有明显的对比优势和应用价值。 展开更多
关键词 多源异构信息融合 多自由度采摘机械臂 位姿数据 驱动控制 控制精度
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舰用雷达阵面在不同冲击环境下的响应分析
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作者 周世新 杨斌 《现代雷达》 CSCD 北大核心 2024年第1期74-78,共5页
通过理论计算和有限元仿真,研究舰用雷达阵面在不同冲击环境下的响应。文中将冲击载荷作用下舰用雷达阵面的受力模型简化为基础激励的多自由度系统,通过对受力模型的边界模态进行虚拟约束的方法计算了不同冲击环境下的响应。结果表明:... 通过理论计算和有限元仿真,研究舰用雷达阵面在不同冲击环境下的响应。文中将冲击载荷作用下舰用雷达阵面的受力模型简化为基础激励的多自由度系统,通过对受力模型的边界模态进行虚拟约束的方法计算了不同冲击环境下的响应。结果表明:舰用雷达阵面响应基本不受冲击谱参数中谱加速度变化的影响,而谱位移和谱速度对舰用雷达阵面响应影响较大。分析结果可为冲击环境下舰用雷达阵面的响应分析和影响评估提供参考。 展开更多
关键词 冲击环境 舰用雷达阵面 多自由度系统 响应分析
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新型3-CPS/RPPS机构的有限元建模及模态分析 被引量:4
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作者 杨德华 Lorenzo Zago +1 位作者 李徽 程刚 《机械设计与制造》 北大核心 2013年第10期93-96,共4页
对新型3-CPS/RPPS型六自由度机构进行有限元建模和模态分析,系统介绍了采用有限元法进行多自由度机构建模和进行模态分析的过程。介绍了新型3-CPS/RPPS机构的机构原理;探讨了采用有限元法进行多自由度机构相关机构分析的可行性;详细介... 对新型3-CPS/RPPS型六自由度机构进行有限元建模和模态分析,系统介绍了采用有限元法进行多自由度机构建模和进行模态分析的过程。介绍了新型3-CPS/RPPS机构的机构原理;探讨了采用有限元法进行多自由度机构相关机构分析的可行性;详细介绍了采用基于静凝聚理论的自由度释放法建立多自由度机构铰链的过程,并修改开源有限元程序CALFEM的3维梁单元实现了铰链的功能;基于MATLAB和CALFEM,对3-CPS/RPPS机构进行简化,建立了基于三维梁单元的有限元模型,进行了模态分析,给出了最低8阶固有频率和前4阶振型。最后探讨了有限元法在多自由度机构或并联机器人机构分析领域的应用前景。 展开更多
关键词 有限元法 有限元建模 模态分析 多自由度机构 并联机器人 机构分析
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DMANet:针对空间非合作目标位姿估计的密集多尺度注意力网络
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作者 张钊 胡瑀晖 +3 位作者 周栋 吴立刚 姚蔚然 李鹏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第1期122-134,共13页
利用单目相机对空间非合作目标进行准确的姿态估计对于空间碎片清除、自主交会和其他在轨服务至关重要。然而,单目姿态估计方法缺乏深度信息,导致尺度不确定性问题,大大降低了其精度和实时性。本文首先提出了一种多尺度注意块(Multi-sca... 利用单目相机对空间非合作目标进行准确的姿态估计对于空间碎片清除、自主交会和其他在轨服务至关重要。然而,单目姿态估计方法缺乏深度信息,导致尺度不确定性问题,大大降低了其精度和实时性。本文首先提出了一种多尺度注意块(Multi-scale attention block, MAB),从输入图像中提取复杂的高维语义特征。其次,基于MAB模块,提出了空间非合作目标6自由度位姿估计的密集多尺度注意网络(Dense multi-scale attention network, DMANet),该网络由平面位置估计、深度位置估计和姿态估计3个分支组成,通过引入基于欧拉角的软分类方法,将位姿回归问题表述为经典分类问题。此外,设计了空间非合作目标模型,并利用Coppeliasim构建了姿态估计数据集。最后,与其他最先进的方法相比,在SPEED+、URSO数据集和本文数据集上全面评估了所提出的方法。实验结果表明,该方法具有较好的姿态估计精度。 展开更多
关键词 六自由度位姿估计 空间非合作目标 多尺度注意力机制 深度学习 神经网络
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