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Bionic soft robotic gripper with feedback control for adaptive grasping and capturing applications

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Frontiers of Mechanical Engineering 2024年第1期19卷 129-148页

作者： Tingke WU Zhuyong liu Ziqi ma Boyang WANG Daolin ma hexi YU Department of Engineering Mechanics School of Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China MOE Key Laboratory of Hydrodynamics Shanghai Jiao Tong UniversityShanghai 200240China

Robots are playing an increasingly important role in engineering *** robots have promising applications in several fields due to their inherent advantages of compliance,low density,and soft interactions.A soft gripper based on bio-inspiration is proposed in this *** analyze the cushioning and energy absorption mechanism of human fingertips in detail and provide insights for designing a soft gripper with a variable stiffness *** investigate the grasping modes through a large deformation modeling approach,which is verified through *** characteristics of the three grasping modes are quantified through testing and can provide guidance for robotics ***,the adaptability of the soft gripper is verified by grasping multi-scale and extremely soft ***,a cushioning model of the soft gripper is proposed,and the effectiveness of cushioning is verified by grasping extremely sharp objects and living ***,we validate the advantages of the variable stiffness of the soft gripper,and the results show that the soft robot can robustly complete assemblies with a gap of only 0.1 *** to the unstructured nature of the engineering environment,the soft gripper can be applied in complex environments based on the abovementioned experimental ***,we design the soft robotics system with feedback capture based on the inspiration of human catching *** feasibility of engineering applications is initially verified through fast capture experiments on moving *** design concept of this robot can provide new insights for bionic machinery.

关键词： soft bionic gripper variable stiffness structure large deformation modeling feedback control soft robotic system

Motion planning for redundant prismatic-jointed manipulators in the free-floating mode

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Acta Mechanica Sinica 2012年第5期28卷 1449-1456页

作者： xiao-dong liu He-Xi baoyin xing-rui ma School of Aerospace Tsinghua University

This paper investigates the motion planning of redundant free-floating manipulators with seven prismatic joints. On the earth, prismatic-jointed manipulators could only position their end-effectors in a desired way. However, in space, the end-effectors of free-floating manipulators can achieve both the desired orientation and desired position due to the dynamical coupling between manipulator and satellite movement, which is formally expressed by linear and angular momentum conservation laws. In this study, a tractable algorithm particle swarm optimization combined with differential evolution （PSODE） is provided to deal with the motion planning of redundant free-floating prismatic-jointed manipulators, which could avoid the pseudo inverse of the Jacobian matrix. The polynomial functions, as argument in sine functions are used to specify the joint paths. The co- efficients of the polynomials are optimized to achieve the desired end-effector orientation and position, and simulta- neously minimize the unit-mass-kinetic energy using the redundancy. Relevant simulations prove that this method pro- vides satisfactory smooth paths for redundant free-floating prismatic-jointed manipulators. This study could help to recognize the advantages of redundant prismatic-jointed space manipulators.

关键词： Motion planning - Prismatic joints - Space manipulators Redundant manipulators Free-floating robots ~Nonholonomic planning

Dynamics of surface motion on a rotating massive homogeneous body

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Science China(Physics,Mechanics & Astronomy) 2013年第4期56卷 818-829页

作者： liu xiaodong baoyin hexi ma xingrui School of Aerospace Tsinghua University

It is of great interest to study the dynamical environment on the surface of non-spherical small bodies, especially for asteroids. This paper takes a simple case of a cube for instance, investigates the dynamics of a particle on the surface of a rotating homogeneous cube, and derives fruitful results. Due to the symmetrical characteristic of the cube, the analysis includes motions on two different types of surfaces. For each surface, both the frictionless and friction cases are considered. (i) Without consideration of friction, the surface equilibria in both of the different surfaces are examined and periodic orbits are derived. The analysis of equilibria and periodic orbits could assist understanding the skeleton of motions on the surface of asteroids. (ii) For the friction cases, the conditions that the particle does not escape from the surface are examined. Due to the effect of the friction, there exist the equilibrium regions on the surface where the particle stays at rest, and the locations of them are found. Finally, the dust collection regions are predicted. Future work will extend to real asteroid shapes.

关键词： surface motion cube asteroids equilibria periodic orbits equilibrium regions non-spherical bodies stability gravity

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目标小行星自主光学搜索策略

清华大学学报（自然科学版） 2024年第9期64卷 1555-1564页

作者：穆硕刘辉宋家隆韩柠段耀武柳澍暄宝音贺西清华大学航天航空学院北京100084 北京控制与电子技术研究所北京100038

近些年来,小行星研究备受关注。小行星不仅具有重要的科研与经济价值,同时也是威胁地球安全的因素之一。对于直径较小或观测数据较少的小行星,其探测和防御任务更具挑战。该文结合中国首个小行星撞击任务,针对定轨误差较大的小直径目标... 详细信息

近些年来,小行星研究备受关注。小行星不仅具有重要的科研与经济价值,同时也是威胁地球安全的因素之一。对于直径较小或观测数据较少的小行星,其探测和防御任务更具挑战。该文结合中国首个小行星撞击任务,针对定轨误差较大的小直径目标小行星,利用光学相机开展撞击任务最终阶段的目标搜索方案研究。该文考虑光学相机性能、星载计算性能以及机动时间等限制因素,设计了一种可最大化单次成像面积的目标搜索方案,并给出了不同搜索次数可覆盖面积的解析表达式,利用几何关系证明推导了不同视野位置的递推计算方法。Monte Carlo数值仿真结果验证了方案的有效性,其搜索成功率可达100%。

关键词：小行星探测小行星撞击光学搜索区域搜索

Hot subduction in the southern Paleo-Asian Ocean:Insights from clinopyroxene chemistry and Sr-Nd-Hf-Pb isotopes of Carboniferous volcanics in West Junggar

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Geoscience Frontiers 2024年第1期15卷 155-174页

作者： Yao xiao Xijun liu Wenjiao xiao xiao-Han Gong Hao Wu Yujia Song Zhiguo Zhang Pengde liu Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration College of Earth SciencesGuilin University of TechnologyGuilin 541004China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resource Guilin University of Technology Guilin 541004China National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China College of Civil Engineering Hexi UniversityZhangye 734000China

The chemical evolution and pressure-temperature conditions of subduction zone magmatism along ancient suture zones in orogenic belts can provide important information regarding plate convergence processes in *** magmatism in West Junggar is key to understanding the tectonothermal and subduction history of the Junggar Ocean,which was a branch of the Paleo-Asian Ocean,as well as the accretionary processes in the southwestern Central Asian Orogenic Belt(CAOB).We undertook a geochronological,mineralogical,geochemical,and Sr-Nd-Hf-Pb isotopic study of volcanic rocks from the Baikouquan area of West *** used these data to determine the petrogenesis,mantle source,and pressure-temperature conditions of these magmas,and further constrain the subduction and tectonic history of the Junggar *** studied volcanic rocks yielded zircon U-Pb ages of 342-337 ma and are characterized by enrichments of large-ion lithophile elements(LILEs),and depletions in high-field-strength elements(HFSEs),indicative of an island arc *** volcanic rocks have positiveƐNd(t)(5.83-7.04)andƐHf(t)(13.47-15.74)values,87Sr/86Sr(t)ratios of 0.704023-0.705658,and radiogenic 207Pb/204Pb(t)and 208Pb/204Pb(t)ratios at a given 206Pb/204Pb(t)ratio,indicative of a depleted mantle source contaminated by subduction-related *** modeling calculations indicate that≤1%of a subduction component comprising fluid and sediment melt could have generated the source of the parental melts of the Baikouquan volcanic *** phenocrysts in the volcanic rocks are classified as high-and low-Ti clinopyroxene,and pressure-temperature calculations suggest the host rocks formed at high temperatures(~1300℃)and shallow to moderate depths(magma was probably generated by hot and hydrous melting in a mantle wedge in response to subduction of young,hot oceanic *** present results,combined with published data,suggest that the Baikouquan volcanic r

关键词： Hot subduction Sr-Nd-Hf-Pb isotopes Clinopyroxene chemistry West Junggar Central Asian Orogenic Belt

SiCp/Al复合材料在常规与超声振动辅助条件的切削过程和表面形成的有限元分析

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制造技术与机床 2024年第4期 51-56页

作者：马国红张加力闫帆施訸曦刘莉太原科技大学机械工程学院山西太原030024 山西黄河呼延建设工程有限公司山西太原030023

SiCp/Al复合材料是一种典型的难加工的材料,由于其基体中颗粒增强导致常规切削中加工质量差、切削阻力高、加工损伤高,机械加工性差,常规切削已不能满足加工要求。通过切削仿真,对比分析常规与超声振动辅助切削条件下复合材料的切削过程... 详细信息

SiCp/Al复合材料是一种典型的难加工的材料,由于其基体中颗粒增强导致常规切削中加工质量差、切削阻力高、加工损伤高,机械加工性差,常规切削已不能满足加工要求。通过切削仿真,对比分析常规与超声振动辅助切削条件下复合材料的切削过程、SiC颗粒的损伤特性、工件的表面形貌与亚表面损伤。结果表明,相比于常规切削,超声振动辅助切削可以提高复合材料的表面完整性,减少复合材料的亚表面损伤,并且能够提高工件的表面质量。

关键词： SiCp/Al复合材料有限元模拟超声振动辅助切削切削机理表面质量

基于GIS的灾害避难所适宜性评价及选址优化研究——以山东省日照市为例

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自然灾害学报 2024年第4期33卷 106-117页

作者：马运佳曲晨希杜贤豪杨雨蒙刘宝印曲阜师范大学地理与旅游学院山东日照276826 临沂孟园实验学校山东临沂276017 中国科学院科技战略咨询研究院北京100190

作为应急管理的重点内容,灾害避难所的选址优化可为制定防灾减灾规划提供参考。以山东省日照市为例,基于GIS空间分析技术,采用起始点-目的地点(origin-destination,O-D)成本矩阵法、道路阻抗模型、Voronoi图算法和P-中值补充选址优化模... 详细信息

作为应急管理的重点内容,灾害避难所的选址优化可为制定防灾减灾规划提供参考。以山东省日照市为例,基于GIS空间分析技术,采用起始点-目的地点(origin-destination,O-D)成本矩阵法、道路阻抗模型、Voronoi图算法和P-中值补充选址优化模型等方法,通过现在避难所的可达性分析、责任区评价及其人口配置缺口分析,多角度评价了日照市现有避难所的适宜性,并设计了3套避难所补充选址优化方案。结果表明:日照市道路交通可达性较高,各道路节点到其他所有节点平均车行时间为34.74~83.40 min,但现有避难所数量不足、空间分布过于集中,制约了现有避难所的可达性,不同辐射半径下,现有避难所可达范围分别仅占全市面积的12.60%、39.54%和78.69%。日照市现有避难所责任区内需跨区避难的乡镇和街道占比达18.52%,2种避难需求情景下,日照市人口配置缺口对应全市81.96%和15.91%的人口,现有避难所难以容纳。3套补充选址优化方案的近期规划方案中,建议新增高新区城市生态公园和开发区中心公园和奎山山地公园等8个公园绿地作为新建避难所。

关键词：灾害避难所 O-D成本矩阵道路阻抗模型 Voronoi图 P-中值模型

β-Catenin Deletion in Regional Neural Progenitors Leads to Congenital Hydrocephalus in Mice

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Neuroscience Bulletin 2022年第1期38卷 81-94页

作者： Lin ma Yanhua Du Xiangjie Xu hexi Feng Yi Hui Nan Li Guanyu Jiang xiaoqing Zhang xiaocui Li Ling liu Translational Medical Center for Stem Cell Therapy Shanghai East HospitalSchool of MedicineTongji UniversityShanghai200120China Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education Orthopaedic Department of Tongji HospitalShanghai200065China Brain and Spinal Cord Innovative Research Center School of MedicineTongji UniversityShanghai200092China Key Laboratory of Neuroregeneration of Shanghai Universities School of MedicineTongji UniversityShanghai200092China Tsingtao Advanced Research Institute Tongji UniversityQingdao266071China Shanghai Institute of Stem Cell Research and Clinical Translation Shanghai200120China Department of Pathology and Pathophysiology School of MedicineTongji UniversityShanghai200092China Department of Immunology and Microbiology Shanghai Institute of ImmunologyShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai First maternity and Infant Hospital School of MedicineTongji UniversityShanghai200092China

Congenital hydrocephalus is a major neurological disorder with high rates of morbidity and mortality;however,the underlying cellular and molecular mechanisms remain largely *** animal models mirroring both embryonic and postnatal hydrocephalus are also ***,we describe a new mouse model of congenital hydrocephalus through knockout ofβ-catenin in Nkx2.1-expressing regional neural *** ventriculomegaly and an enlarged brain were consistently observed in knockout mice from embryonic day 12.5 through to *** profiling revealed severe dysfunctions in progenitor maintenance in the ventricular zone and therefore in cilium biogenesis afterβ-catenin *** analyses also revealed an aberrant neuronal layout in both the ventral and dorsal telencephalon in hydrocephalic mice at both embryonic and postnatal ***,knockout ofβ-catenin in regional neural progenitors leads to congenital hydrocephalus and provides a reproducible animal model for studying pathological changes and developing therapeutic interventions for this devastating disease.

关键词： Congenital hydrocephalus β-Catenin Ependymal cells Nkx2.1 Neural development

Eolian origin of the Miocene loess-soil sequence at Qin'an,China:Evidence of quartz morphology and quartz grain-size

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Chinese Science Bulletin 2006年第1期51卷 117-120页

作者： liu Jinfeng GUO Zhengtang QIAO Yansong HAO Qingzheng YUAN baoyin Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China

Recent study revealed that the so-called Neogene Gansu System in the western Loess Plateau contains loess-soil sequences of Miocene age ([1]). A most complete sequence (QA-1) covers a time interval from similar to 22 to similar to 6.2 ma BP, consisting of more than 230 visually definable paleosols interbedded with loess layers([1]). A loess-soil sequence of late Miocene-Pliocene age, synchronous with the Hipparian Red Clay in the eastern Loess Plateau, was also recognized 121, and extends the Miocene sequences into the Pliocene, similar to 3.5 ma BR Recently, Miocene eolian deposits were also reported 131 from the high terraces near Xining([3]). Eolian origin of the Miocene sequences near Qin'an is supported by several lines of evidence, including micromorphological, sedimentological and geochemical data([1]). Here, we further examine the morphology and sedimentological characteristics of more samples covering the entire QA-I sequence, to provide additional evidence of the eolian origin. Quartz is a dominant mineral component of eolian dust deposits([4,5]). Because of its stable physical and chemical properties under surface conditions, grain morphology of the quartz is usually used to deter,mine the sources, transportation dynamics and post-depositional modifications of the sediments([1,4-6]). Grain-size of the quartz fraction is also better reflective to that of the original eolian dust as quartz is resistant to Post-depositional chemical weathering in the semi-arid/semi-humid loess regions([7,8]). In this study, grain-morphology and grain-size distributions of the quartz fraction from the QA-I sequence are examined, and compared with those of the typical eolian deposits of Quaternary age from the Xifeng site.

关键词：石英形态尺寸中新世黄土