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2021全球十大工程成就 2

多角度成像光谱辐射计 1

大规模多输入多输出；球面波假设；非稳定性；生灭过程；散射体可见区域法 1

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Dynamical research on spherical micro actuator with piezoelectric ceramic stacks drivers

ZHANG Ruihua, CHEN Haichu

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 433-438 doi: 10.1007/s11465-007-0074-y

摘要： This paper develops a 30 mm × 30 mm × 50 mm spherical micro actuator driven by piezoelectric ceramic stacks (PZT), and analyzes its dynamic performances. First, the space coordinate relationship of the spherical micro actuator and a dynamic model are set up. Second, The Runge-Kutta arithmetic is used to calculate the dynamical parameters of the micro actuator; the SIMULINK module of MATLAB is used to build the dynamical simulating model and then simulate it. Third, an experimental sample of the spherical micro actuator is developed, a micromanipulator is integrated with a micro-gripper based on the sample spherical micro actuator, and the experimental research on the micro assembly is conducted between a micro shaft of 180 μm and a micro spindle sleeve of 200 μm. Finally, the characteristics of the spherical micro actuator influenced by the mass of the metal sphere of the micro actuator, driving signal frequency, friction coefficient of the contact surface between the metal sphere and the friction block of the micro driving unit are analyzed. The experimental results indicate that the rotation resolution of the micro actuator reaches 0.000 1°, the rotation positioning precision reaches 0.000 5°, and the maximum working frequency is about 1200 Hz. The experimental results validate the back rotation vibration model of the spherical micro actuator. The micromanipulator integrated by the spherical micro actuator can meet the requirements of precise micro operation and assembly for micro electro mechanical systems (MEMS) or other microelements in micro degree fields.

关键词： spherical     micro-gripper     friction coefficient     dynamic     frequency    

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Development of a redundant anthropomorphic hydraulically actuated manipulator with a roll–pitch–yaw spherical

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 698-710 doi: 10.1007/s11465-021-0646-2

摘要： The demand for redundant hydraulic manipulators that can implement complex heavy-duty tasks in unstructured areas is increasing; however, current manipulator layouts that remarkably differ from human arms make intuitive kinematic operation challenging to achieve. This study proposes a seven-degree-of-freedom (7-DOF) redundant anthropomorphic hydraulically actuated manipulator with a novel roll–pitch–yaw spherical wrist. A hybrid series–parallel mechanism is presented to achieve the spherical wrist design, which consists of two parallel linear hydraulic cylinders to drive the yaw/pitch 2-DOF wrist plate connected serially to the roll structure. Designed as a 1R PRRR-1S PU mechanism (“R”, “P”, “S”, and “U” denote revolute, prismatic, spherical, and universal joints, respectively; the underlined letter indicates the active joint), the 2-DOF parallel structure is partially decoupled to obtain simple forward/inverse kinematic solutions in which a closed-loop subchain “R PRR” is included. The 7-DOF manipulator is then designed, and its third joint axis goes through the spherical center to obtain closed-form inverse kinematic computation. The analytical inverse kinematic solution is drawn by constructing self-motion manifolds. Finally, a physical prototype is developed, and the kinematic analysis is validated via numerical simulation and test results.

关键词： hydraulic manipulator     inverse kinematic     redundant design     spherical wrist    

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Synthesis and electrocatalytic property of cubic and spherical nanoparticles of cobalt platinum alloys

Xiaowei TENG, Hong YANG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 45-51 doi: 10.1007/s11705-009-0308-0

摘要： This paper describes the morphological control and electrocatalytic property of CoPt nanoparticles. Both cubic and spherical CoPt nanoparticles were made using cobalt carbonyl and platinum 2,4-pentanedionate under different reaction temperatures in the presence of capping reagents, which included adamantanecarboxylic acid and hexadecylamine. Effects of heterogeneous species on shape of the CoPt nanoparticles were examined by replacing cobalt carbonyl with silver acetylacetonate. Our results suggest that the formation of different shapes of CoPt particles could be attributed to the affinity between cobalt and platinum, and the effects of capping agents. The size and shape dependent electrocatalytic properties of these nanoparticles were examined based on the direct methanol oxidation reaction.

关键词： spherical     2     4-pentanedionate     adamantanecarboxylic     acetylacetonate     electrocatalytic    

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On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

《机械工程前沿（英文）》 2014年 第9卷 第1期   页码 34-40 doi: 10.1007/s11465-014-0290-1

摘要：

As the instant centers in planar mechanisms, the instantaneous poles (or instant poles, in brief) can be used for kinematic analysis in spherical mechanisms. One of the mandatory steps in this analysis is the determination of the location of these poles. This paper presents a theorem showing analytically that the locus of an unknown secondary instant pole in two-degree-of-freedom (2-DOF) spherical mechanisms is a great circle (GC). The exact location of the pole on its GC is obtained based on the configuration of the mechanism and velocity ratio of the two inputs. Moreover, using the results of the theorem, a geometrical technique is presented to determine the GC of the pole.

关键词： spherical mechanisms     instantaneous poles     great circle     angular velocity    

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Singularity loci of an orthogonal spherical two-degree-of-freedom parallel mechanism

Jialun YANG, Feng GAO,

《机械工程前沿（英文）》 2009年 第4卷 第4期   页码 379-385 doi: 10.1007/s11465-009-0075-0

摘要： Singularity analysis plays an important role in the design of robots, especially for parallel robots. In this paper, the direct and inverse kinematics of an orthogonal spherical two-degree-of-freedom parallel mechanism is proposed based on the modified Euler angles. All the singular poses of the mechanism are achieved through the direct kinematic analysis. Self-motions, which are different from the general spherical 5 parallel mechanisms, are also discussed. Singularity loci in the joint space and Cartesian space are plotted according to the Jacobin of the mechanism. Result shows that the singularity loci at the joint space are two circles and one line, whereas at the Cartesian space are a circle.

关键词： 2-DOF orthogonal spherical parallel mechanism     singularity loci     self-motions    

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A survey of instantaneous poles for a class of two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

《机械工程前沿（英文）》 2014年 第9卷 第4期   页码 344-353 doi: 10.1007/s11465-014-0320-z

摘要：

This paper is a detailed exploration of instantaneous poles for a class of two-degree-of-freedom (two-DOF) spherical mechanisms (SMs) with seven links or bars. For two-DOF SMs, the secondary instantaneous poles (the ones which cannot be found by direct inspection) must lie on the specified great circles. For many of these mechanisms, however, some of these great circles cannot be obtained by a direct application of Aronhold-Kennedy theorem. This paper presents geometrical and analytical techniques to locate these unknown great circles for three topologies of seven-bar two-DOF SMs.

关键词： spherical mechanisms     instantaneous poles     Aronhold-Kennedy theorem     great circles     pencil of meridian    

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Shape optimization of aluminium alloy spherical reticulated shells considering nonlinearities

Wei LIU; Lishu XU; Shaojun ZHU; Lijuan LI; Feng LIU; Zhe XIONG

《结构与土木工程前沿（英文）》 2022年 第16卷 第12期   页码 1565-1580 doi: 10.1007/s11709-022-0867-4

摘要： This study proposes a shape optimization method for K6 aluminum alloy spherical reticulated shells with gusset joints, considering geometric, material, and joint stiffness nonlinearities. The optimization procedure adopts a genetic algorithm in which the elastoplastic non-linear buckling load is selected as the objective function to be maximized. By confinement of the adjustment range of the controlling points, optimization results have enabled a path toward achieving a larger elastoplastic non-linear buckling load without changing the macroscopic shape of the structure. A numerical example is provided to demonstrate the effectiveness of the proposed method. In addition, the variation in structural performance during optimization is illustrated. Through parametric analysis, practical design tables containing the parameters of the optimized shape are obtained for aluminum alloy spherical shells with common geometric parameters. To explore the effect of material nonlinearity, the optimal shapes obtained based on considering and not considering material non-linear objective functions, the elastoplastic and elastic non-linear buckling loads, are compared.

关键词： shape optimization     aluminum alloy     spherical reticulated shell     non-linear buckling     material nonlinearity     genetic algorithm    

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Atomic force microscopy study on the microtopography of natural organic matter and newly formed hydrous MnO2

GUO Jin, MA Jun, SHI Xuehua

《环境科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 251-256 doi: 10.1007/s11783-007-0043-z

摘要： To understand the water purification mechanism of potassium permanganate as a coagulation-aid during the preoxidation process, the microtopography of its reductive products, the newly formed hydrous manganese dioxide and the aged hydrous manganese dioxide, was investigated. The morphology of natural organic matter (NOM) adsorbed by the newly formed hydrous manganese dioxide was also compared with that of NOM alone. By using the tapping mode atomic force microscopy (AFM), the observation results show that the newly formed hydrous manganese dioxide possess a perforated sheet (with a thickness of 0 1.75 nm) as well as some spherical particle structures compared with the hydrous manganese dioxide with 2 h aging time, which demonstrated that the newly formed hydrous manganese dioxide had a large surface area and adsorption capacity. When 1 mmol/L newly formed hydrous manganese dioxide was added, the microtopography of NOM molecules shifted from a loosely dispersed pancake shape (with adsorption height of 5 8.5 nm) to a densely dispersed and uniform spherical structure. These results provide a valid proof that it is the perfect adsorption capability of the newly formed hydrous manganese dioxide that might result in the coagulation aid effect of potassium permanganate preoxidation.

关键词： spherical     microtopography     potassium permanganate     uniform spherical     morphology    

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Elastic analysis of heterogeneous thick-walled spherical pressure vessels with parabolic varying properties

Keyhan KARAMI, Majid ABEDI, Mohammad ZAMANI NEJAD, Mohammad Hassan LOTFIAN

《机械工程前沿（英文）》 2012年 第7卷 第4期   页码 433-438 doi: 10.1007/s11465-012-0336-1

摘要：

On the basis of plane elasticity theory (PET), the displacement and stress components in a thick-walled spherical pressure vessels made of heterogeneous materials subjected to internal and external pressure is developed. The mechanical properties except the Poisson’s ratio are assumed to obey the parabolic variations throughout the thickness. Effect of material inhomogeneity on the elastic deformations and stresses is investigated. The analytical solutions and the solutions carried out through the FEM have a good agreement. The values used in this study are arbitrary chosen to demonstrate the effect of inhomogeneity on displacements, and stresses distributions.

关键词： thick-walled spherical vessels     heterogeneous materials     FGM     FEM     parabolic varying properties    

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Synthesis of spherical parallel manipulator for dexterous medical task

Abdelbadia CHAKER, Abdelfattah MLIKA, Med Amine LARIBI, Lotfi ROMDHANE, Sa?d ZEGHLOUL

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 150-162 doi: 10.1007/s11465-012-0325-4

摘要：

This paper deals with the design and the analysis of a spherical parallel manipulator (SPM) for a haptic minimally invasive surgery application. First the medical task was characterized with the help of a surgeon who performed a suture technique called anastomosis. A Vicon system was used to capture the motion of the surgeon, which yielded the volume swept by the tool during the anastomosis operation. The identified workspace can be represented by a cone with a half vertex angle of 26°. A multi objective optimization procedure based on genetic algorithms was then carried out to find the optimal SPM. Two criteria were considered, i.e., task workspace and mechanism dexterity. The optimized SPM was then analyzed to determine the error on the orientation of the end effector as a function of the manufacturing errors of the different links of the mechanism.

关键词： spherical parallel manipulator (SPM)     anastomosis     haptic     motion capture     optimization     workspace     dexterity     genetic algorithm     manufacturing errors    

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Buffer capacity of granular matter to impact of spherical projectile based on discrete element method

Ying YAN, Pengfei LI, Shunying JI

《结构与土木工程前沿（英文）》 2013年 第7卷 第1期   页码 50-54 doi: 10.1007/s11709-013-0186-x

摘要： Granular matter possesses impact-absorbing property due to its energy dissipation character. To investigate the impact-absorbing capacity of granular matter, the discrete element method (DEM) is adopted to simulate the impact of a spherical projectile on to a granular bed. The dynamic responses of the projectile are obtained for both thin and thick granular bed. The penetration depth of the projectile and the first impact peak are investigated with different bed thicknesses and impact velocities. Determining a suitable bed thickness is crucial to the buffering effect of granular matter. The first impact peak is independent of bed thickness when the thickness is larger than the critical thickness.

关键词： granular matter     impact peak     buffer capacity     discrete element method     critical thickness    

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Flow behavior of non-spherical particle flowing in hopper

He TAO,Wenqi ZHONG,Baosheng JIN

《能源前沿（英文）》 2014年 第8卷 第3期   页码 315-321 doi: 10.1007/s11708-014-0331-9

摘要： Ellipsoidal particles flowing in the hopper were simulated by using the discrete element method (DEM), and described by the multi-element method. The contact detection algorithm and equations for ellipsoidal particle motion in hopper were developed. And the simulation results were confirmed by experiment. Additionally, the mass flow rate, pressure distribution and velocity distribution of two kinds of particles were examined. The results show that the mass flow rate of ellipsoidal particles is smaller than that of spherical particles. There is a maximum value of pressure drop at the top of the junction. Besides, the pressure drop decreases with the discharging time increasing. The velocity of spherical particle is larger than that of ellipsoidal.

关键词： discrete element method     ellipsoidal particle     flow behavior     hopper    

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Orderly decorated nanostructural photoelectrodes with uniform spherical TiO

A. M. Bakhshayesh,S. S. Azadfar

《化学科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 532-540 doi: 10.1007/s11705-015-1549-8

摘要： This study presents a novel nanostructural electrode made of 20-nm-diameter nanoparticles, which orderly decorated with 2-µm TiO particles, deposited by a new gel process. The decorated electrode (DE) is better than the non-decorated electrode (NE) in both light scattering and light harvesting, as confirmed by diffuse reflectance spectroscopy. X-ray diffraction reveals that both electrodes have a mixture of anatase and rutile phases. The dye-sensitized solar cell based on the decorated electrode shows the highest power conversion efficiency of 7.80% as a result of less recombination demonstrated by electrochemical impedance spectroscopy. From internal power conversion efficiency measurement, the external quantum efficiency of DE cell at 530 nm is 89%, which is higher than that of NE cell (77%).

关键词： dye-sensitized solar cell     uniform particles     TiO2 gel process     light harvesting    

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Selective removal of phenol by spherical particles of

Qingchuan CHEN, Yicun WEN, Yu CANG, Li LI, Xuhong GUO, Rui ZHANG

《化学科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 162-169 doi: 10.1007/s11705-013-1318-5

摘要： Spherical particles of -, - and -cyclodextrin (CD) polymers to efficiently remove phenol from waste water were prepared by reverse suspension polymerization with epichlorohydrin as crosslinker in liquid paraffin. By controlling the amounts of crosslinker and water, well-defined spherical polymer particles with controllable size were obtained. Due to the selective inclusion associations between CD groups and phenol, these CD spherical polymer particles were demonstrated to be ideal candidates for removal of phenol. Among them -CD polymer particles showed the best performance. The kinetics and isothermal equilibrium models were used to fit the experimental data of phenol removal from aqueous solution using these CD polymer particles. It was found that the kinetics followed the Ho and Mckay equation, suggesting that the adsorption process of phenol was controlled by diffusion and the host-guest interaction between CD and phenol. Equilibrium isothermal data can be well fitted by the Freundlich equation. The negative free energy change indicated the spontaneous nature of adsorption of phenol by -, - and -CD spherical polymer particles, while the lowest free energy for -CD polymer reflected its best adsorption ability, compared to - and -CD polymer particles.

关键词： cyclodextrin polymer particles     phenol     kinetic models     adsorption isotherm equilibrium models    

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控制结晶工艺制备球形材料

何向明,王莉,任建国,蒲薇华,姜长印,万春荣

《中国工程科学》 2006年 第8卷 第7期   页码 36-41

摘要：

介绍了利用控制结晶工艺制备球形结晶颗粒的理论依据、设备和工艺参数，并给出了利用控制结晶技术制备高密度球形电池活性材料的基本工艺过程；所制备的材料性能测试及电化学性能测试结果表明，控制结晶工艺制备的正极材料具有球形化好、密度高、流散性好、电化学活性高等优点。

关键词： 控制结晶工艺     球形     电池活性材料     高密度    

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标题 作者 时间 类型 操作

Dynamical research on spherical micro actuator with piezoelectric ceramic stacks drivers

ZHANG Ruihua, CHEN Haichu

期刊论文

Development of a redundant anthropomorphic hydraulically actuated manipulator with a roll–pitch–yaw spherical

期刊论文

Synthesis and electrocatalytic property of cubic and spherical nanoparticles of cobalt platinum alloys

Xiaowei TENG, Hong YANG,

期刊论文

On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

期刊论文

Singularity loci of an orthogonal spherical two-degree-of-freedom parallel mechanism

Jialun YANG, Feng GAO,

期刊论文

A survey of instantaneous poles for a class of two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

期刊论文

Shape optimization of aluminium alloy spherical reticulated shells considering nonlinearities

Wei LIU; Lishu XU; Shaojun ZHU; Lijuan LI; Feng LIU; Zhe XIONG

期刊论文

Atomic force microscopy study on the microtopography of natural organic matter and newly formed hydrous MnO2

GUO Jin, MA Jun, SHI Xuehua

期刊论文

Elastic analysis of heterogeneous thick-walled spherical pressure vessels with parabolic varying properties

Keyhan KARAMI, Majid ABEDI, Mohammad ZAMANI NEJAD, Mohammad Hassan LOTFIAN

期刊论文

Synthesis of spherical parallel manipulator for dexterous medical task

Abdelbadia CHAKER, Abdelfattah MLIKA, Med Amine LARIBI, Lotfi ROMDHANE, Sa?d ZEGHLOUL

期刊论文

Buffer capacity of granular matter to impact of spherical projectile based on discrete element method

Ying YAN, Pengfei LI, Shunying JI

期刊论文

Flow behavior of non-spherical particle flowing in hopper

He TAO,Wenqi ZHONG,Baosheng JIN

期刊论文

Orderly decorated nanostructural photoelectrodes with uniform spherical TiO

A. M. Bakhshayesh,S. S. Azadfar

期刊论文

Selective removal of phenol by spherical particles of

Qingchuan CHEN, Yicun WEN, Yu CANG, Li LI, Xuhong GUO, Rui ZHANG

期刊论文

控制结晶工艺制备球形材料

何向明,王莉,任建国,蒲薇华,姜长印,万春荣

期刊论文