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Design and Experiments of an Origami-Inspired Pneumatic Flexible Manipulator

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Acta Mechanica Solida Sinica 2023年第2期36卷 254-261页

作者： Benzhu Guo Panding Wang Zeang Zhao shengyu duan Hongshuai Lei Beijing Key Laboratory of Lightweight Multi-Functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China

Unlike traditional manipulators with high rigidity and limited degrees of freedom,pneumatic manipulators have significant superiorities such as flexibility,lightweight and cleanliness,and therefore,have been one of the most popular research directions in ***,most existing pneumatic manipulators have disadvantages such as low rigidity and simple *** order to make up for the shortcomings of existing pneumatic manipulators,this paper proposes a new pneumatic flexible manipulator inspired by the concept of origami,which realizes the combination and balance of flexibility and *** element analysis is conducted to study influences of the number of airbags,the angle of main beam,and the width of main beam on the performance of the flexible *** simulation results are utilized to optimize the structure of the flexible manipulator.A pneumatic control system is designed to realize the automatic control of the pneumatic flexible *** the same time,a prototype is 3D printed,the experimental platform for pneumatic deformation is built,and the verification experiments of the single-jaw manipulator and the three-jaw manipulator are completed.

关键词： Origami-inspired design Flexible structure Pneumatic drive Finite element analysis Pneumatic control system

Improved quadratic isogeometric element simulation of one-dimensional elastic wave propagation with central difference method

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Applied Mathematics and Mechanics(English Edition) 2018年第5期39卷 703-716页

作者： Weibin WEN Shibin LUO shengyu duan Jun LIANG Daining FANG School of Civil Engineering Central South University State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology College of Engineering Peking University

Two improved isogeometric quadratic elements and the central difference scheme are used to formulate the solution procedures of transient wave propagation prob- lems. In the proposed procedures, the lumped matrices corresponding to the isogeomet- ric elements are obtained. The stability conditions of the solution procedures are also acquired. The dispersion analysis is conducted to obtain the optimal Courant-Friedrichs- Lewy （CFL） number or time-step sizes corresponding to the spatial isogeometric elements. The dispersion analysis shows that the isogeometric quadratic element of the fourth-order dispersion error （called the isogeometric analysis （IGA）-f quadratic element） provides far more desirable numerical dissipation/dispersion than the element of the second-order dis- persion error （called the IGA-s quadratic element） when appropriate time-step sizes are selected. The numerical simulations of one-dimensional （1D） transient wave propagation problems demonstrate the effectiveness of the proposed solution procedures.

关键词： structural dynamics wave propagation isogeometric analysis (IGA) numerical dissipation time integration

An improved time integration scheme based on uniform cubic B-splines and its application in structural dynamics

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Applied Mathematics and Mechanics(English Edition) 2017年第6期38卷 889-908页

作者： Weibin WEN Hongshuai LEI Kai WEI Baosheng XU shengyu duan Daining FANG College of Engineering Peking UniversityBeijing 100871China Beijing Institute of Technology Beijing 100081China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body School of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Key Laboratory of Applied Mechanics Department of Engineering MechanicsSchool of Aerospace EngineeringTsinghua UniversityBeijing 100084China

A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom （SDOF） system, and then is generalized for a multiple-degree of freedom （MDOF） system. Stability analysis shows that, with an adjustable algorithmic parameter, the proposed method can achieve both conditional and unconditional stabilities. Validity of the method is shown with four numerical simulations. Comparison between the proposed method and other methods shows that the proposed method possesses high computation accuracy and desirable computation efficiency.

关键词： dynamical system time integration~ stability dynamic response B-spline

A novel hybrid design method of lattice structure based on failure mode

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Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 79-91页

作者： Chuanlei Li Junfeng Qi Panding Wang Zeang Zhao Zhe Wang Hongshuai Lei shengyu duan Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Spacecrafts Beijing 100094China

Adjusting the mechanical properties of lattice structures is important for many modern application fields. In this paper, a new design method for hybrid multi-layer lattice structures was developed to improve the mechanical properties and energy absorption, by altering and suppressing the formation of the shear band. In these hybrids, all unit cells were divided into two parts:(i) diagonal unit cells and(ii) matrix unit cells. Four categories of unit cells were selected to construct the hybrid multi-layer structures. The compressive moduli, ultimate strengths, and energy absorption properties of the laser powder bed fusion(L-PBF)fabricated structures were assessed by experiments and finite element analysis(FEA). The results revealed the great impact of diagonal unit cells on the mechanical properties of the structures. Stronger diagonal unit cells than matrix unit cells led to hybrid structures with enhanced mechanical properties. Compared with a uniform body-centered cubic(BCC) lattice structure, the relative density of the lattice structure consisting of the weakest BCC matrix unit cells and strongest BFVC diagonal unit cells(coupling of BCC, FCC, and VC) exhibited an increase of 20%. The compressive modulus and ultimate strength of this structure rose by more than 200% and 90%, respectively. Two types of structures with specific properties were generated by hybrid *** first displayed higher modulus, superior strength, and elevated specific energy absorption(SEA) but lower crash load efficiency(CLE). The second illustrated simultaneously higher SEA and elevated CLE. The present results provide a new insight for improving the load-bearing and energy absorption capacities of lattice structures.

关键词： additive manufacturing lattice structure shear deformation hybrid mechanical properties

Adaptive enhancement design of triply periodic minimal surface lattice structure based on non-uniform stress distribution

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1317-1330页

作者： Yijin ZHANG Bin LIU Fei PENG Heran JIA Zeang ZHAO shengyu duan Panding WANG Hongshuai LEI Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

The Schwarz primitive triply periodic minimal surface(P-type TPMS)lattice structures are widely ***,these lattice structures have weak load-bearing capacity compared with other cellular *** this paper,an adaptive enhancement design method based on the non-uniform stress distribution in structures with uniform thickness is proposed to design the P-type TPMS lattice structures with higher mechanical *** types of structures are designed by adjusting the adaptive thickness distribution in the *** keeps the same relative density,and the other keeps the same of non-enhanced region *** with the uniform lattice structure,the elastic modulus for the structure with the same relative density increases by more than 17%,and the yield strength increases by more than 10.2%.Three kinds of TPMS lattice structures are fabricated by laser powder bed fusion(L-PBF)with 316L stainless steel to verify the proposed enhanced *** manufacture-induced geometric deviation between the as-design and as-printed models is measured by micro X-ray computed tomography(μ-CT)*** quasi-static compression experimental results of P-type TPMS lattice structures show that the reinforced structures have stronger elastic moduli,ultimate strengths,and energy absorption capabilities than the homogeneous P-TPMS lattice structure.

关键词： additive manufacturing(AM) triply periodic minimal surface(TPMS) enhanced design model mechanical property micro X-ray computed tomography(u-CT)

Real-world insights for the evolving intervention strategy for non-mild acute pancreatitis: 35-year experience in a Chinese Tertiary Center

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胰腺病学杂志(英文) 2024年第2期07卷 111-118页

作者： Yan Xiaxiao Zhou Jingya Cao Jian Xu Qiang Han Xianlin Wang duan Zhang shengyu Wu Dong Department of Gastroenterology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Medical Records Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China WHO Family of International Classifications Collaborating Center of China Beijing China Department of Radiology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of General Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China

Background: With the accumulation of experience and evidence, guidelines for invasive intervention for acute pancreatitis (AP) have continuously evolved, followed in Peking Union Medical College Hospital (PUMCH). We aimed to review AP case series to help understand the impact of guideline evolution on the management and prognosis of AP in real-world ***: This was a single-center study of AP patients who had received invasive interventions from 1988 to 2022. Patient demographics, baseline severity, imaging findings, and the indication, timing, and specific modalities of invasive interventions were collected. The composite primary endpoint was death during hospitalization or major complications after intervention. Other endpoints included pancreatic fistula, incision infection, number of interventions, length of intensive care stay, length of hospitalization, and total medical ***: A total of 195 patients were included. The most common indication for invasive intervention was suspected infection, followed by persistent symptoms. The step-up and delayed strategies reduced the incidence of major complications or death. Over 35 years, the number of patients requiring surgery has gradually declined, and more patients need only minimally invasive procedures for remission. The incidence of the primary outcome decreased as well as the duration of ***: The management of AP patients at PUMCH in the last 35 years has undergone therapeutic guideline changes that support the efficacy and safety of the deferred step-up strategy in real-world practice.

关键词： Acute pancreatitis Drainage Invasive intervention Necrosectomy Step-up

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阶梯式消能在坝口河水库溢洪洞中的应用

水利技术监督 2019年第1期27卷 239-242页

作者：段胜禹邱勇陈秋蓉王尚今李鑫龙云南农业大学水利学院云南昆明650201

为了减轻出口建筑物的消能压力和降低对下游河道的有害性冲刷,同时避免出口消能后的水体溶解气体过饱和,在山区泄水建筑物泄槽段可考虑布置阶梯,以加糙固体边界。基于坝口河水库溢洪洞原布置设计,通过水工模型试验,研究在第一泄槽段增... 详细信息

为了减轻出口建筑物的消能压力和降低对下游河道的有害性冲刷,同时避免出口消能后的水体溶解气体过饱和,在山区泄水建筑物泄槽段可考虑布置阶梯,以加糙固体边界。基于坝口河水库溢洪洞原布置设计,通过水工模型试验,研究在第一泄槽段增设阶梯后,原反弧段末端(阶梯末端)以及消力池进口水流流速和动能的变化。成果表明:消力池进口水流流速和动能的降低,有效缓解了消力池内水体紊动,下游河道水体掺气明显减轻。

关键词：特征工况流速及能量变化小流量水流流态生态效益阶梯消能

增材制造三维点阵结构设计、优化与性能表征方法研究进展

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航空制造技术 2022年第14期65卷 36-48,57页

作者：段晟昱王潘丁刘畅赵则昂周浩张啸雨雷红帅郭旭方岱宁北京理工大学北京100081 大连理工大学大连116023 中国空间技术研究院北京100094

增材制造技术与三维点阵结构技术是航空航天装备结构实现轻量化与多功能化的重要途径。针对增材制造三维点阵结构及其设计方法进行概述,重点介绍了增材制造三维点阵结构工程应用、轻质多功能三维点阵结构构型设计方法、三维点阵结构多... 详细信息

增材制造技术与三维点阵结构技术是航空航天装备结构实现轻量化与多功能化的重要途径。针对增材制造三维点阵结构及其设计方法进行概述,重点介绍了增材制造三维点阵结构工程应用、轻质多功能三维点阵结构构型设计方法、三维点阵结构多尺度计算方法与拓扑优化方法、增材制造三维点阵结构性能评价表征方法等方面的研究现状与进展,对增材制造三维点阵结构在材料–结构–功能一体化设计方面的发展趋势进行了展望。

关键词：增材制造(AM) 点阵结构结构设计拓扑优化性能表征

生防菌代谢产物与化学杀菌剂对棉花枯萎病菌的抑制活性研究

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安徽科技学院学报 2024年第1期38卷 65-70页

作者：周慧段海明杨胜雨张健安徽科技学院农学院安徽凤阳233100

目的:为更有效防治棉花枯萎病和研制新型生物农药提供技术依据,本研究探究生防菌代谢产物与化学杀菌剂对棉花枯萎病菌(Fusarium oxysporum f. ***)的抑制活性。方法:采用对峙培养法、菌丝生长速率法测定生防菌、发酵上清液、脂肽粗提物... 详细信息

目的:为更有效防治棉花枯萎病和研制新型生物农药提供技术依据,本研究探究生防菌代谢产物与化学杀菌剂对棉花枯萎病菌(Fusarium oxysporum f. ***)的抑制活性。方法:采用对峙培养法、菌丝生长速率法测定生防菌、发酵上清液、脂肽粗提物以及化学杀菌剂对棉花枯萎病菌的抑制特性。结果:对峙培养法得出生防菌SJ06对棉花枯萎病菌的抑制率为78.24%。发酵上清液的浓度从6.25μL/mL增至100.00μL/mL对病菌的抑制率从46.90%增至80.30%,其对病菌的EC50为7.37μL/mL;脂肽粗提物的质量浓度从673.96μg/mL增至8 120.00μg/mL对病菌的抑制率从19.90%增至77.30%,对病菌的EC50为2 720.20μg/mL。棉花枯萎病菌对多菌灵、戊唑醇的敏感性较高,戊唑醇和多菌灵对病菌的EC50分别为0.34、0.49μg/mL;其次分别为腈菌唑、苯醚甲环唑和丙环唑,其对病菌的EC50分别为1.07、1.34、1.54μg/mL,而丙森锌对病菌的抑制活性较差,EC50为63.25μg/mL。结论:解淀粉芽孢杆菌发酵代谢物和戊唑醇等麦角甾醇生物合成抑制剂对棉花枯萎病菌具有较好的抑制活性。

关键词：棉花枯萎病生防菌代谢产物化学杀菌剂