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A force feedback master finger in exoskeleton type

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High Technology Letters 2010年第3期16卷 299-305页

作者： Fang Honggen Liu Hong Xie Zongwu State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 P.R. China Institute of Robotics and Mechatronic German Aerospace Center Wessling DLR 82230 Germany

In order to eliminate the drawbacks of conventional force feedback gloves, a new type of master finger has been developed. By utilizing three "four-bar mechanism joint" in series and wire coupling mechanism, the master finger transmission ratio is kept exactly 1: 1.4: 1 in the whole movement range and it can make active motions in both extension and flexion directions. Additionally, to assure faster data transmission and near zero delay in the master-slave operation, a digital signal processing/field programmable gate array (DSP/FPGA-FPGA) structure with 200 μs cycle time is designed. The operating modes of the master finger can be contact or non-contact, which depends on the motion states of a slave finger, free motion or constrained motion. The position control employed in non-contact mode ensures unconstrained motion and the force control adopted in contact mode guarantees natural contact sensation. To evaluate the performances of the master finger, an experiment between the master finger and a DLR/HIT dexterous finger is conducted. The results demonstrate that this new type master finger can augment telepresence. © by High Technology Letters Press.

关键词：手指反馈型现场可编程门阵列骨骼数字信号处理运动范围 FPGA 接触模式

The Anlysis of Follow - up Data after Physical Examination for Modification Equipment in F- 6 Pilots

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美国中华健康卫生杂志 2005年第4期8卷 34-37页

作者： XU Xianrong LI Hongqi LIU Hongjin JIN Zhanguo center of Clinic Aviation medicine PLA General Hospital of Air Force Beijing 100036 China

Influence of velocity profile on calibration function of Lorentz force flowmeter

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Applied Mathematics and Mechanics(English Edition) 2014年第8期35卷 993-1004页

作者： C.STELIAN 于洋李本文 A.THESS Institute of Thermodynamics and Fluid Mechanics Ilmenau University of TechnologyIlmenau 98684Germany Department of Physics West University of TimisoaraTimisoara 300233Romania Key Laboratory of Electromagnetic Processing of Materials Northeastern University Institute of Engineering Thermodynamics German Aerospace CenterStuttgart 70569Germany

A Lorentz force flowmeter is a noncontact electromagnetic flow-measuring device based on exposing a flowing electrically conducting liquid to a magnetic field and measuring the force acting on the magnet system. The measured Lorentz force is proportional to the flow rate via a calibration coefficient which depends on the velocity distribution and magnetic field in liquid. In this paper, the influence of different velocity profiles on the calibration coefficient is investigated by using numerical simulations. The Lorentz forces are computed for laminar flows in closed and open rectangular channels, and the results are compared with the simplified case of a solid conductor moving at a constant velocity. The numerical computations demonstrate that calibration coefficients for solid bodies are always higher than for liquid metals. Moreover, it can be found that for some parameters the solid-body calibration coefficient is almost twice as high as for a liquid metal. These differences are explained by analyzing the patterns of the induced eddy currents and the spatial distributions of the Lorentz force density. The result provides a first step for evaluating the influence of the laminar velocity profiles on the calibration function of a Lorentz force flowmeter.

关键词： laminar flow numerical simulation electromagnetic velocimetry

An anthropomorphic controlled hand prosthesis system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第10期13卷 769-780页

作者： Hai HUANG Hong LIU Nan LI Li JIANG Da-peng YANG Lei WAN Yong-jie PANG Gerd HIRZINGER National Key Laboratory of Science and Technology on Autonomous Underwater Vehicle Harbin Engineering University Harbin 150001 China State Key Laboratory of Robot and Systems Harbin Institute of Technology Harbin 150001 Chin Institute of Robotics and Mechatronics German Aerospace Center DLR Wessling 82230 Germany

Based on HIT/DLR(Harbin Institute of Technology/Deutsches Zentrum für Luft-und Raumfahrt) Prosthetic Hand II,an anthropomorphic controller is developed to help the amputees use and perceive the prosthetic hands more like people with normal physiological *** core of the anthropomorphic controller is a hierarchical control *** is composed of a top controller and a low level *** top controller has been designed both to interpret the amputee's intensions through electromyography(EMG) signals recognition and to provide the subject-prosthesis interface control with electro-cutaneous sensory feedback(ESF),while the low level controller is responsible for grasp *** control strategies include the EMG control strategy,EMG and ESF closed loop control strategy,and voice control *** EMG signal recognition,10 types of hand postures are recognized based on support vector machine(SVM).An anthropomorphic closed loop system is constructed to include the customer,sensory feedback system,EMG control system,and the prosthetic hand,so as to help the amputee perform a more successful EMG *** results suggest that the anthropomorphic controller can be used for multi-posture recognition,and that grasp with ESF is a cognitive dual process with visual and sensory *** process while outperforming the visual feedback process provides the concept of grasp force magnitude during manipulation of objects.

关键词： Anthropomorphic controller Prosthetic hand EMG recognition Electro-cutaneous sensory feedback

Therapeutic effect of a traditional Chinese medicine formulation on experimental choroidal neovascularization in mouse

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International Journal of Ophthalmology(English edition) 2021年第10期14卷 1492-1500页

作者： Yu-Fei Zhang Chuan Jiang Xiao-Hong Zhou Dong-Yu Wei Shao-Heng Li Pan Long Man-Hong Li Zuo-Ming Zhang Tao Chen Hong-Jun Du center of Clinical aerospace medicine Fourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina The air force Hospital from Northern Theater PLA Shenyang 110092Liaoning ProvinceChina Department of Aviation medicine Xijing HospitalFourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina Ophthalmology Children’s Hospital of Fudan UniversityShanghai 201102China School of Basic medicine Fourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina Department of Ophthalmology General HospitalWestern Theater CommandChengdu 610083Sichuan ProvinceChina Department of Ophthalmology Xijing HospitalFourth Military Medical UniversityXi’an 710032Shaanxi ProvinceChina

AIM:To investigate therapeutic effects of traditional Chinese medicine formulations,Hexuemingmu(HXMM)on laser-induced choroidal neovascularization(CNV)and followup effect in ***:C57 BL/6 mice of 8-week-old were used and CNV was induced with 577 nm laser *** were randomly divided into groups and different doses of HXMM were administered ***,four,and eight weeks after the intervention,the electroretinogram(ERG),fundus fluorescence angiography,choroidal flat mount and immunofluorescence staining were preformed to evaluate the function and CNV *** expression levels of angiogenic proteins were determined by Western blotting and immunofluorescence *** analysis of variance and Kruskal-Wallis test were used to test the differences among the ***:The results showed that HXMM effectively increased amplitude of ERG of mice(P<0.05),alleviated fundus CNV leakage(P<0.05),and reduced the area of neovascularization and the expression of angiogenic proteins(P<0.05)after laser-induced ***:HXMM can protect the retinal function of mice after laser-induced CNV,and inhibit the CNV development.

关键词： choroidal neovascularization traditional Chinese medicine mice

Mechanical force drives the polarization and orientation of cells

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Acta Mechanica Sinica 2019年第2期35卷 275-288页

作者： Shijie He Xiaomeng Li Baohua Ji center for Engineering in medicine Massachusetts General Hospital Harvard Medical School Boston MA 02114 USA Department of Applied Mechanics School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China

Collective cells are organized to form specific patterns which play important roles in various physiological and pathological processes, such as tissue morphogenesis, wound healing, and cancer invasion. Compared to single cell behaviors, which has been intensively studied from many aspects (cell migration, adhesion, polarization, proliferation, etc.) and at various scales (molecular, subcellular, and cellular), the multiple cell behaviors are relatively less understood, particularly in a quantitative manner. In this paper, we will present our recent studies of collective polarization and orientation of multiple cells through both experimental measurement and theoretical modeling, including those cell behaviors on/in 2D and 3D substrate/tissue. We find that the collective cell behaviors, including polarization, alignment and migration are closely related to local stress states in cell layer or tissue, which demonstrate the crucial roles of mechanical forces in the living organisms. Specifically, the cells prefer to polarize and align along the maximum principal stress in the cell layer, and the aspect ratio of cell increases with the in-plane maximum shear stress, suggesting that the maximum shear stress is the underlying driving force of cell polarization and orientation. This theory of stress-driven cell behaviors of polarization and orientation provides a new perspective for understanding cell behaviors in living organisms and the guideline for tissue engineering in biomedical applications.

关键词： Collective cell behaviors Cell polarization Cell alignment Quantification Cell mechanosensing

A Study on the End-Effector Exchange Mechanism of a Space Robot

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Journal of Mechanics Engineering and Automation 2017年第5期7卷 278-284页

作者： Rui Qu Yuto Takei Mitsushige Oda Hiroki Nakanishi Armin Wedler Kent Yoshikawa Department of Mechanical and aerospace Engineering Tokyo Institute of Technology Tokyo 1528550 Japan RMC (Robotics and Mechatronics CenteO DLR (German Aerospace Center) Oberpfaffenhofen 82234 Germany

Retinal neovascularization induced by mutant Vldlr gene inhibited in an inherited retinitis pigmentosa mouse model:an in-vivo study

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International Journal of Ophthalmology(English edition) 2021年第7期14卷 990-997页

作者： Wei-Ming Yan Pan Long Mei-Zhu Chen Dong-Yu Wei Jian-Cong Wang Zuo-Ming Zhang Lei Zhang Tao Chen Department of Ophthalmology the 900^(th)Hospital of Joint Logistic Support Forceo of PLA(Clinical Medical College of Fujian Medical UniversityDongfang Hopsital Affiliated to Xiamen University)Fuzhou 350025Fujian ProvinceChina center of Clinical aerospace medicine Air Force Medical UniversityXi’an 710032Shaanxi ProvinceChina Department of Ophthalmology the West General Hospital of Chinese PLAChengdu 610083Sichuan ProvinceChina BeiJing HealthOLight Technology Co. Ltd.Beijing 10010China Shaanxi Eye Hospital Xi’an People’s Hospital(Xi’an Fourth Hospital)Affiliated Guangren HospitalSchool of MedicineXi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina

AIM:To explore whether the retinal neovascularization(NV)in a genetic mutant mice model could be ameliorated in an inherited retinitis pigmentosa(RP)mouse,which would help to elucidate the possible mechanism and prevention of retinal NV diseases in ***:The Vldlr^(-/-)mice,the genetic mutant mouse model of retinal NV caused by the homozygous mutation of Vldlr gene,with the rd1 mice,the inherited RP mouse caused by homozygous mutation of Pde6b gene were *** of the above two mice led to the birth of the F1 hybrids,further inbreeding of which gave birth to the F2 *** ocular genotypes and phenotypes of the mice from all generations were examined,with the F2 offspring grouped according to the ***:The rd1 mice exhibited the RP phenotype of outer retinal degeneration and loss of retinal *** Vldlr^(-/-)mice exhibited the phenotype of retinal NV obviously shown by the fundus fluorescein *** F1 hydrides,with the heterozygote genotype,exhibited no phenotypes of RP or retinal *** F2 offspring with homozygous genotypes were grouped into four *** were the F2-Ⅰmice with the wild-type Pde6b and Vldlr genes(Pde6b~(+/+)-Vldlr~(+/+)),which had normal ocular phenotypes;the F2-Ⅱmice with homozygous mutant Vldlr gene(Pde6b~(+/+)-Vldlr^(-/-)),which exhibited the retinal NV phenotype;the F2-Ⅲmice with homozygous mutant Pde6b gene(Pde6b^(-/-)-Vldlr~(+/+)),which exhibited the RP ***,the F2-Ⅳmice with homozygous mutant Vldlr and Pde6b gene(Pde6b^(-/-)-Vldlr^(-/-))showed only the RP phenotype,without the signs of retinal ***:The retinal NV can be inhibited by the RP phenotype,which implies the role of a hyperoxic state in treating retinal NV diseases.

关键词： retinitis pigmentosa retinal neovascularization Pde6b gene Vldlr gene photoreceptor

Green's function for T-stress of semi-infinite plane crack

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Applied Mathematics and Mechanics(English Edition) 2011年第8期32卷 973-980页

作者：崔元庆杨卫仲政 School of aerospace Engineering and Applied Mechanics Tongji University Office of the Presidents Zhejiang University

Green’s function for the T-stress near a crack tip is addressed with an analytic function method for a semi-infinite crack lying in an elastical, isotropic, and infinite plate. The cracked plate is loaded by a single inclined concentrated force at an interior point. The complex potentials are obtained based on a superposition principle, which provide the solutions to the plane problems of elasticity. The regular parts of the potentials are extracted in an asymptotic analysis. Based on the regular parts, Green’s function for the T-stress is obtained in a straightforward manner. Furthermore, Green’s functions are derived for a pair of symmetrically and anti-symmetrically concentrated forces by the superimposing method. Then, Green’s function is used to predict the domain-switch-induced T-stress in a ferroelectric double cantilever beam （DCB） test. The T-stress induced by the electromechanical loading is used to judge the stable and unstable crack growth behaviors observed in the test. The prediction results generally agree with the experimental data.

关键词： Green’s function T-stress complex variable function semi-infinite crack fracture mechanics