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环形桁架式空间薄膜展开机构运动精度可靠性建模与分析

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航天器环境工程 2024年第1期41卷 34-42页

作者：尹大勇胡明孟少华高云吴梅北京卫星环境工程研究所北京100094 浙江理工大学机械工程学院杭州310018

空间薄膜展开机构的姿态和位置精度会对薄膜索网的工作形态产生影响。文章首先构建环形桁架式空间薄膜展开机构运动精度可靠性理论模型,然后基于ADAMS建立考虑展开机构杆长误差的参数化仿真模型,并采用蒙特卡罗法对展开机构进行运动精... 详细信息

空间薄膜展开机构的姿态和位置精度会对薄膜索网的工作形态产生影响。文章首先构建环形桁架式空间薄膜展开机构运动精度可靠性理论模型,然后基于ADAMS建立考虑展开机构杆长误差的参数化仿真模型,并采用蒙特卡罗法对展开机构进行运动精度可靠性仿真分析,求解运动精度可靠度。结果表明,以机构展开到位时折展杆支撑点所拟合的空间圆心坐标位置误差及半径误差作为其运动精度可靠性量化评价指标是正确的。该研究可为空间薄膜展开机构的可靠性设计提供参考。

关键词：环形桁架空间薄膜展开机构运动精度可靠性可靠性建模可靠性仿真

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双L支架回扣式压电俘能器:设计与实验

电子测量与仪器学报 2024年第6期38卷 34-41页

作者：赵庆玲宋汝君罗莲健王郭泰周海安山东理工大学机械工程学院淄博255000

为了获得一种便携式、简单的振动俘能器,克服传统俘能器输出低、频率高等问题,提出了一种双L支架回扣式压电俘能器,结合了张拉结构的非线性特性与压电技术,有效提高了俘能系统的动态响应和输出性能。对俘能器进行实验探究,分析了外接电... 详细信息

为了获得一种便携式、简单的振动俘能器,克服传统俘能器输出低、频率高等问题,提出了一种双L支架回扣式压电俘能器,结合了张拉结构的非线性特性与压电技术,有效提高了俘能系统的动态响应和输出性能。对俘能器进行实验探究,分析了外接电阻值、磁距、激振加速度和角度等因素对俘能器输出性能的影响。实验结果表明,俘能器存在最优外接电阻值使输出功率达到峰值,最优外接电阻值为200 kΩ。磁力的引入能显著提高俘能器的输出性能。在磁铁距离为18 mm时,俘能器俘获的能量最多,其最佳输出性能在12.1 Hz时达到1.12 mW。此外,激振加速度对俘能系统的输出特性有着显著影响,激振加速度越大,俘能器的输出电压与输出功率也随之增大。在激振加速度为0.4 g,频率为12 Hz的条件下,俘能系统达到了1.39 mW的最大输出功率。双L支架回扣式俘能器在0°~45°角度范围内具有良好的输出电压与输出功率,具有在不确定激振方向条件下工作的优势。实际应用实验进一步证明,该俘能器能够持续输出较大且稳定的电压,为解决传统俘能器输出低等问题提供了有效的解决方案。

关键词：振动能双L支架磁力压电俘能

医用可降解Zn-Sn-Cu合金的力学及腐蚀性能研究

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热加工工艺 2024年第4期53卷 70-74页

作者：黄庆利任伊宾马玉豪武夏鹏沈阳理工大学材料科学与工程学院辽宁沈阳110159

可生物降解锌及其合金具有良好的生物相容性和降解速率,在生物医用材料领域具有广阔的应用前景。但纯锌的力学性能不足,如强度低、可塑性差,限制了其临床应用。在此,采用重力铸造制备了新的三元Zn-3Sn-x Cu(x=0,1,2,3wt%)合金,旨在通过... 详细信息

可生物降解锌及其合金具有良好的生物相容性和降解速率,在生物医用材料领域具有广阔的应用前景。但纯锌的力学性能不足,如强度低、可塑性差,限制了其临床应用。在此,采用重力铸造制备了新的三元Zn-3Sn-x Cu(x=0,1,2,3wt%)合金,旨在通过与铜(Cu)的微合金化来获得良好的耐腐蚀性和生物相容性,并提高力学性能。通过金相分析、拉伸试验、显微硬度测试以及电化学和浸泡试验,分析其微观结构、力学性能及耐蚀性能。结果表明,Cu的加入,使得合金具有更高的强度和硬度;体外降解试验表明:Zn-3Sn-x Cu(x=0,1,2,3wt%)合金的降解速率较Zn-3Sn合金有较幅的提升,满足可降解医用材料的标准,有望成为一种新型可降解医用材料。

关键词： Zn-Sn-Cu锌基合金力学性能生物相容性可降解

Controllable Bending of Bi-hydrogel Strips with Differ ent ial Swelling

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Acta Mechanica Solida Sinica 2019年第5期32卷 652-662页

作者： Yi wu Xingpeng Hao Rui Xiao Ji Lin Zi Liang wu Jun Yin Jin Qian Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Department of Engineering MechanicsZhejiang UniversityHangzhou 310027China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Key Laboratory of 3D Printing Process and Equipment of Zhejiang ProvinceSchool of Mechanical EngineeringZhejiang UniversityHangzhou 310028China

Bi-hydrogel strips consisting of a highly swelling layer and a non-swelling layer are investigated in this study,in which the differential swelling capabilities and mismatch strain in the composite structure drive the strips into a bending configuration when being exposed to solvents.A modified analytical model originated from Timoshenko theory on bi-material beam is proposed to predict the swelling-induced bending shape of the bi-hydrogel strips,with explicit relations of bending curvature and mid-span deflection versus mismatch *** sets of experiments were performed to verify the analytical model and its solutions,in which the swellinginduced mismatch strain was systematically tuned by the selection of saline *** broad agreements bet ween the t heore tical and experimen tai results indicate that the modified analytical model can be used to guide the design of morphing elements by modulating layer-bylayer mismatches in gel composites to produce precise and complex shape transformations for practical applications.

关键词： Bi-hydrogel strip Hydrogel swelling Mismatch strain Shape morphing Analytical model

基于RegNet-CSAM与ZOA-KELM模型的滚动轴承故障诊断

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振动与冲击 2024年第11期43卷 165-175页

作者：戚晓利王兆俊毛俊懿王志文崔德海赵方祥安徽工业大学机械工程学院安徽马鞍山243032

针对现有深度卷积神经网络对滚动轴承混合故障诊断效果不佳以及模型复杂度过高导致计算成本过大等问题,提出了一种基于RegNet-CSAM与ZOA-KELM模型的滚动轴承故障诊断方法。该模型由RegNet-CSAM网络和ZOA-KELM分类算法组成。首先,将融合... 详细信息

针对现有深度卷积神经网络对滚动轴承混合故障诊断效果不佳以及模型复杂度过高导致计算成本过大等问题,提出了一种基于RegNet-CSAM与ZOA-KELM模型的滚动轴承故障诊断方法。该模型由RegNet-CSAM网络和ZOA-KELM分类算法组成。首先,将融合了通道和空间特征的注意力机制CSAM与组卷积残差模块结合,提升该结构的表征能力,由此构建的RegNet-CSAM网络,模型复杂度为0.48GF;其次,在分类阶段将斑马优化核极限学习机(ZOA-KELM)替代原来网络中使用的Softmax函数完成最后的分类任务。滚动轴承故障诊断试验结果表明,RegNet网络对滚动轴承混合故障样本容易产生误判,CSAM的融入虽将RegNet网络的分类精度进一步提高,但是仍然存在一定程度的滚动轴承混合故障误判问题;而将ZOA-KELM替代Softmax函数后再对RegNet-CSAM网络输出特征进行分类,能够有效识别出滚动轴承的单一和混合故障,准确率达到了99.92%。所提方法对比其他网络,诊断精度最大提升5.02%,模型复杂度最大缩减32倍。

关键词：故障诊断滚动轴承组卷积残差结构注意力机制斑马优化核极限学习机(ZOA-KELM)

A New Grasping Mode Based on a Sucked-type Underactuated Hand

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Chinese Journal of mechanical engineering 2018年第6期31卷 25-33页

作者： Pei-Chen wu Nan Lin Ting Lei Qian Cheng Jin-Ze wu Xiao-Ping Chen school of Computer Science and Technology University of Science and Technology of China Hefei 230000 China

Robot hands have been developing during the last few decades. There are many mechanical structures and analyti?cal methods for di erent hands. But many tough problems still limit robot hands to apply in homelike environment. The ability of grasping objects covering a large range of sizes and various shapes is fundamental for a home service robot to serve people better. In this paper, a new grasping mode based on a novel sucked?type underactuated(STU) hand is proposed. By combining the flexibility of soft material and the e ect of suction cups, the STU hand can grasp objects with a wide range of sizes, shapes and materials. Moreover, the new grasping mode is suitable for some situations where the force closure is failure. In this paper, we deduce the e ective range of sizes of objects which our hand using the new grasping mode can grasp. Thanks to the new grasping mode, the ratio of grasping size between the biggest object and the smallest is beyond 40, which makes it possible for our robot hand to grasp diverse objects in our daily life. For example, the STU hand can grasp a soccer(220 mm diameter, 420 g) and a fountain pen(9 mm diameter, 9 g). What’s more, we use the rigid body equilibrium conditions to analysis the force condition. Experiment evaluates the high load capacity, stability of the new grasping mode and displays the versatility of the STU hand. The STU hand has a wide range of applications especially in unstructured environment.

关键词： Grasping mode Underactuated hand Sucked?type Stability of new mode Grasping diverse objects

Synthesis,functionalization,and nanomedical applications of functional magnetic nanoparticles

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Chinese Chemical Letters 2018年第11期29卷 1601-1608页

作者： Zhou Chen Cao wu Zhenfeng Zhang Wangping wu Xuefeng Wang Zhiqiang Yu school of mechanical and Power engineering Nanjing Tech University International Laboratory for Insulation and Energy Efficiency Materials College of Materials Science and TechnologyNanjing University of Aeronautics and Astronautics Shandong Huaying New Material Co. Ltd. school of mechanical engineering Changzhou University Department of Obstetrics and Gynecology Zhujiang HospitalSouthern Medical University Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical SciencesSouthern Medical University

Synthesis of magnetic nanoparticles （MNPs） is one of the most active research areas in advanced materials. MNPs that have magnetic properties and other functionalities have been demonstrated to show great promise in nanomedical applications. This review summarizes the current MNPs preparation, functionalization and stabilization methods. It also analyzes the detailed features of MNPs. And furthermore it highlights some actual case analyses of these MNPs for disease therapy, drug delivery, hyperthermia, bioseparation and bioimaging applications.

关键词： Magnetic nanoparticles Synthesis Functionalization Medical applications Nanomedicine

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基于人工蜂群算法的机器人运动学参数标定

机械工程师 2024年第3期 44-46,51页

作者：蔡鑫宇赵铁军沈阳工业大学机械工程学院沈阳110027

为了提高机器人的绝对定位精度,针对经典的D-H模型,使用修正的MD-H模型来描述IRB 120型机器人的运动模型,避免了运动过程中出现的奇异现象。对末端位置测量采用的方法是单目视觉测量,由于传统的位置误差模型需要计算出机器人基坐标系和... 详细信息

为了提高机器人的绝对定位精度,针对经典的D-H模型,使用修正的MD-H模型来描述IRB 120型机器人的运动模型,避免了运动过程中出现的奇异现象。对末端位置测量采用的方法是单目视觉测量,由于传统的位置误差模型需要计算出机器人基坐标系和测量坐标系之间的转换矩阵,故采用距离误差模型,可消除坐标系转换所带来的误差。此外,针对最小二乘法容易陷入局部寻优、结果不稳定的问题,提出了人工蜂群算法(ABC)求解高维非线性方程组,对两种方法进行对比。结果表明,人工蜂群算法优于最小二乘法,且使机器人的距离误差精度提高了54.97%。

关键词： MD-H模型距离误差模型运动学标定人工蜂群

Stretchable,skin-conformable neuromorphic system for tactile sensory recognizing and encoding

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InfoMat 2023年第12期5卷 87-99页

作者： Mengge wu Qiuna Zhuang Kuanming Yao Jian Li Guangyao zhao Jingkun Zhou Dengfeng Li Rui Shi Guoqiang Xu Yingchun Li Zijian Zheng Zhihui Yang Junsheng Yu Xinge Yu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China(UESTC)Chengduthe People's Republic of China Department of Biomedical engineering City University of Hong KongHong Kongthe People's Republic of China Laboratory for Advanced Interfacial Materials and Devices School of Fashion and TextilesThe Hong Kong Polytechnic UniversityHong Kongthe People's Republic of China Hong Kong Center for Cerebra-Cardiovascular Health engineering Hong Kong Science ParkHong Kongthe People's Republic of China College of Science Harbin Institute of TechnologyShenzhenthe People's Republic of China Department of Pathology The Affiliated Hospital of Southwest Medical UniversityLuzhouthe People's Republic of China

Expanding wearable technologies to artificial tactile perception will be of significance for intelligent human-machine interface,as neuromorphic sensing devices are promising candidates due to their low energy consumption and highly effective operating ***-compatible and conformable features are required for the purpose of realizing wearable artificial tactile ***,we report an intrinsically stretchable,skin-integrated neuromorphic system with triboelectric nanogenerators as tactile sensing and organic electrochemical transistors as information *** integrated system provides desired sensing,synaptic,and mechanical characteristics,such as sensitive response(~0.04 kPa^(-1))to low-pressure,short-and long-term synaptic plasticity,great switching endurance(>10000 pulses),symmetric weight update,together with high stretchability of 100%*** neural encoding,demonstrations are capable of recognizing,extracting,and encoding features of tactile *** work provides a feasible approach to wearable,skin-conformable neuromorphic sensing system with great application prospects in intelligent robotics and replacement prosthetics.

关键词： neural encoding neuromorphic sensing system organic electrochemical transistors tactile sensation triboelectric nanogenerators