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Development of a Tactile and Slip Sensor with a Biomimetic Structure-enhanced Sensing Mechanism

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Journal of Bionic Engineering 2019年第1期16卷 47-55页

作者： Yonggang Jiang Zhiqiang Ma Bonan Cao Longlong Gong Lin Feng deyuan zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 100191China

Tactile and slip sensors have gained tremendous attention for their promising applications in the fields of smart robotics,implantable medical devices and minimally invasive surgery.Inspired by the structure-enhanced sensing mechanisms of human fingertips and tree frog toes,we developed a tactile and slip sensor by combining biomimetic surface microstructures with highly sensitive P(VDF-TrFE)nanofiber sensors on a flexible polyimide substrate.As the surface microstructures could mediate the micro-vibration induced by slip motion,the frequencies of output signals revealed a strong correlation with the periods of microstructures.In addition,we proposed a method to discriminate touch force from slip motion using the criterion of standard deviation of time delay from the output signals of neighboring sensor elements.

关键词： tactile sensor slip detection nanofiber microstructure biomimetic sensing

Feasibility study of wave-motion milling of carbon fiber reinforced plastic holes

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International Journal of Extreme Manufacturing 2021年第1期3卷 86-96页

作者： deyuan zhang Zhenyu Shao Daxi Geng Xinggang Jiang Yihang Liu ZehuaZhou Shaomin Li School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191People’s Republic of China The Institute of Bionic and Micro-Nano Systems Beihang UniversityBeijing 100191People’s Republic of China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191People’s Republic of China

Carbon fiber reinforced plastic(CFRP)has been applied in aeronautics,aerospace,automotive and medical industries due to its superior mechanical properties.However,due to its difficult-to-cut characteristic,various damages in twist drilling and chip removal clog in core drilling could happen,inevitably reducing hole quality and hole-manufacturing efficiency.This paper proposes the wave-motion milling(WMM)method for CFRP hole-manufacturing to improve hole quality.This paper presents a motion path model based on the kinematics of the WMM method.The wave-motion cutting mode in WMM was analyzed first.Then,comparison experiments on WMM and conventional helical milling(CHM)of CFRP were carried out under dry conditions.The results showed that the hole surface quality of the CFRP significantly improved with a decrease of 18.1%–36%of Ra value in WMM compared to CHM.WMM exerted a significantly weaker thrust force than that of CHM with a reduction of 12.0%–24.9%and 3%–7.7%for different axial feed per tooth and tangential feed per tooth,respectively.Meanwhile,the hole exit damages significantly decreased in WMM.The average tear length at the hole exit in WMM was reduced by 3.5%–29.5%and 35.5%–44.7%at different axial feed per tooth and tangential feed per tooth,respectively.Moreover,WMM significantly alleviated tool wear.The experimental results suggest that WMM is an effective and promising strategy for CFRP hole-manufacturing.

关键词： carbon fiber reinforced plastic wave-motion milling cutting force surface integrity

不同加热环境下钛表面Ni/Al涂层制备与高温氧化性

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表面技术 2024年第1期53卷 192-201页

作者：李光全李德元张楠楠范喜宁沈阳工业大学沈阳110870

目的研究大气与真空加热处理后Ni/Al涂层的金属间化合物析出规律,以及扩散层的生长速度,从而确定涂层的抗氧化性能。方法分别采用电弧喷涂技术和等离子喷涂技术在纯钛基体表面制备Ni/Al涂层。将样品分别在大气条件和真空条件下进行加... 详细信息

目的研究大气与真空加热处理后Ni/Al涂层的金属间化合物析出规律,以及扩散层的生长速度,从而确定涂层的抗氧化性能。方法分别采用电弧喷涂技术和等离子喷涂技术在纯钛基体表面制备Ni/Al涂层。将样品分别在大气条件和真空条件下进行加热处理,使Ni/Al涂层原位反应生成Ni-Al金属间化合物,并进行涂层抗氧化性试验。结果 Ni/Al涂层在大气环境700℃加热处理后,形成以Al_(2)O_(3)、Ni2Al3和富Al相NiAl3相为主的扩散层;在真空环境700℃加热处理后,形成以Ni2Al3、NiAl3相为主的扩散层。通过扩散反应动力学分析发现,真空热处理比大气热处理后Ni和Al之间的反应扩散系数更高,扩散系数为89.731μm2/h。氧化增重试验表明,真空处理后,Ni/Al涂层由于金属间化合物层较厚,且具有大量的高熔点的Ni2Al3相,并且经过800℃下氧化200h后,涂层未发生失效。结论真空环境下加热处理原位反应后,Ni/Al复合涂层的扩散速率更高,更容易形成Ni-Al金属间化合物,获得更厚的金属间化合物层。与大气热处理相比,经过真空热处理后的涂层有更良好的抗高温氧化能力。

关键词： Ni/Al涂层等离子喷涂电弧喷涂 Ni-Al金属间化合物高温氧化热处理

Bio-inspired drag reduction surface from sharkskin

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Biosurface and Biotribology 2018年第2期4卷 39-45页

作者： Dengke Chen Yang Liu Huawei Chen deyuan zhang School of Mechanical Engineering and Automation Beihang UniversityHaidian DistrictBeijingPeople's Republic of China

Nature evolution provides nature surface treasures with special and fascinating surface function to inspiredesign,such as the drag reduction of sharkskin.In this overview,the morphology and mechanism of the sharkskinexplained from different aspects,and various methods of fabricating surfaces with sharkskin morphology areillustrated in details,and then the applications in different fluid engineering are demonstrated in brief.This overviewwill improve the comprehension of the morphology and mechanisms of sharkskin,and methods of fabricating thesurface with morphology,and the recent applications in engineering.

关键词： surface details mechanism

基于嵌入式传感技术的混凝土结构概率损伤成像方法

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建筑结构学报 2024年第6期45卷 143-152页

作者：张明辉周德源何斌陈洪兵孔庆钊同济大学结构防灾减灾工程系上海200092 同济大学电子与信息工程学院上海200092 北京科技大学土木与资源工程学院北京100083 上海韧性城市与智能防灾工程技术研究中心上海200092

混凝土结构损伤的早期预警与精准量化是土木工程结构健康监测领域的热点。提出了一种基于嵌入式传感技术的混凝土结构概率损伤成像方法,通过对混凝土材料中骨料、砂浆基体以及界面过渡区的二维细观有限元建模,揭示了探测应力波在不均匀... 详细信息

混凝土结构损伤的早期预警与精准量化是土木工程结构健康监测领域的热点。提出了一种基于嵌入式传感技术的混凝土结构概率损伤成像方法,通过对混凝土材料中骨料、砂浆基体以及界面过渡区的二维细观有限元建模,揭示了探测应力波在不均匀性混凝土材料及损伤界面的传播机制。结合传感器阵列的损伤可视化机理,设计了一种嵌入式压电传感器阵列模块,为精准量化混凝土损伤,结合概率损伤成像方法,通过基线相减法和希尔伯特变换从探测信号中提取损伤散射波的传播时间信息,引入累积分布函数,实现对混凝土损伤区域的可视化重构。试验结果表明,嵌入式传感模块可实现对混凝土结构的三维损伤成像,且识别出损伤中心位置与真实损伤中心位置在二维投影面上的误差为1.0 cm,验证了该方法对混凝土损伤感知的有效性与准确性。相比于现有嵌入式稀疏分布传感器,多传感单元集成的阵列模块可明显提升对混凝土局部损伤的探知能力,同时降低传感器系统在服役期的运维成本。

关键词：结构健康监测混凝土结构细观有限元模型压电传感器嵌入式压电传感阵列模块概率损伤成像

不锈钢表面Al/Cu涂层制备与第一性原理计算

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沈阳工业大学学报 2024年第2期46卷 165-171页

作者：李德元李光全张楠楠沈阳工业大学材料科学与工程学院辽宁沈阳110870

为了研究Al/Cu涂层中金属间化合物的生成顺序和形成机理,在304不锈钢基体表面制备了Al/Cu涂层。对试样进行热处理使得Al/Cu涂层原位反应生成金属间化合物,随后测试了涂层的高温抗氧化性能。采用第一性原理计算Al-Cu金属间化合物的焓、... 详细信息

为了研究Al/Cu涂层中金属间化合物的生成顺序和形成机理,在304不锈钢基体表面制备了Al/Cu涂层。对试样进行热处理使得Al/Cu涂层原位反应生成金属间化合物,随后测试了涂层的高温抗氧化性能。采用第一性原理计算Al-Cu金属间化合物的焓、熵、吉布斯自由能和热容等数据。将热力学和扩散动力学相结合,提出有效生成自由能模型来预测化合物在Al/Cu界面的生成顺序。结果表明:Al/Cu涂层中首先形成Al_(2)Cu相,在Al/Cu界面处出现了AlCu相,加热时间增加至20 h后出现了富Cu的Al_(4)Cu_(9)相。由第一性原理计算得出,Al-Cu金属间化合物的形成顺序为Al_(2)Cu→AlCu→Al_(4)Cu_(9),与实验结果一致。此外,氧化实验结果表明,涂层具有良好高温抗氧化性能。

关键词： Al/Cu涂层 304不锈钢电弧喷涂等离子喷涂第一性原理计算金属间化合物抗高温氧化热处理

Fundamental Trackability Problems for Iterative Learning Control

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自动化学报:英文版 2023年第10期10卷 1933-1950页

作者： deyuan Meng Jingyao zhang Seventh Research Division Beihang University(BUAA)Beijing 100191China School of Automation Science and Electrical Engineering Beihang University(BUAA)Beijing 100191China

Generally, the classic iterative learning control(ILC)methods focus on finding design conditions for repetitive systems to achieve the perfect tracking of any specified trajectory,whereas they ignore a fundamental problem of ILC: whether the specified trajectory is trackable, or equivalently, whether there exist some inputs for the repetitive systems under consideration to generate the specified trajectory? The current paper contributes to dealing with this problem. Not only is a concept of trackability introduced formally for any specified trajectory in ILC, but also some related trackability criteria are established. Further, the relation between the trackability and the perfect tracking tasks for ILC is bridged, based on which a new convergence analysis approach is developed for ILC by leveraging properties of a functional Cauchy sequence(FCS). Simulation examples are given to verify the effectiveness of the presented trackability criteria and FCS-induced convergence analysis method for ILC.

关键词： Convergence functional Cauchy sequence(FCS) iterative learning control(ILC) trackability

Research and clinical translation of trilayer stent-graft of expanded polytetrafluoroethylene for interventional treatment of aortic dissection

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Regenerative Biomaterials 2022年第1期9卷 650-664页

作者： Gang Wang Caiyun Gao Benhao Xiao Jie zhang Xunyuan Jiang Qunsong Wang Jingzhen Guo deyuan zhang Jianxiong Liu Yuehui Xie Chang Shu Jiandong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China R&D Center Lifetech Scientific(Shenzhen)Co.Ltd.Shenzhen 518057China Department of Vascular Surgery the Second Xiangya Hospital of Central South UniversityChangsha 410011China State Key Laboratory of Cardiovascular Diseases Center of Vascular SurgeryFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100037China

The aortic dissection(AD)is a life-threatening disease.The transcatheter endovascular aortic repair(EVAR)affords a minimally invasive technique to save the lives of these critical patients,and an appropriate stent-graft gets to be the key medical device during an EVAR procedure.Herein,we report a trilayer stent-graft and corresponding delivery system used for the treatment of the AD disease.The stent-graft is made of nitinol stents with an asymmetric Z-wave design and two expanded polytetrafluoroethylene(ePTFE)membranes.Each of the inner and outer surfaces of the stent-graft was covered by an ePTFE membrane,and the two membranes were then sintered together.The biological studies of the sintered ePTFE membranes indicated that the stent-graft had excellent cytocompatibility and hemocompatibility in vitro.Both the stent-graft and the delivery system exhibited satisfactory mechanical properties and operability.The safety and efficacy of this stent-graft and the corresponding delivery system were demonstrated in vivo.In nine canine experiments,the blood vessels of the animals implanted with the stent-grafts were of good patency,and there were no thrombus and obvious stenosis by angiography after implantation for 6months.Furthermore,all of the nine clinical cases experienced successful implantation using the stent-graft and its postrelease delivery system,and the 1-year follow-ups indicated the preliminary safety and efficacy of the trilayer stent-graft with an asymmetric Z-wave design for interventional treatment.

关键词： aortic dissection stent-graft expanded polytetrafluoroethylene delivery system for interventional treatment clinical translation of biomaterials

Reconfigurable Vortex-like Paramagnetic Nanoparticle Swarm with Upstream Motility and High Body-length Ratio Velocity

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Research 2023年第4期2023卷 361-377页

作者： Luyao Wang Han Gao Hongyan Sun Yiming Ji Li Song Lina Jia Chutian Wang Chan Li deyuan zhang Ye Xu Huawei Chen Lin Feng School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China Center of Soft Matter Physics and Its Applications Beihang UniversityBeijing 100191China.

Drug delivery systems with high-targeted doses can minimize excipients,reduce side effects,and improve efficacy.Human blood circulation is a complex circulatory system,and the motion control of microrobots in the static flow field in vitro is completely different from in vivo.How to achieve precise counterflow motion for targeted drug delivery without vascular blockage and immune rejection is the biggest challenge for micro-nano robots.Here,we propose a control method that enables vortex-like paramagnetic nanoparticle swarm(VPNS)to move upstream against the flow.By mimicking the clustering motion of wild herring schools and the rolling of leukocytes,VPNS are incredibly stable even when subjected to high-intensity jet impacts in the blood environment,can travel upstream,anchor at the target location,and dissipate when the magnetic field is withdrawn,which greatly reduces the risk of thrombosis.VPNS can also upstream along the vessel wall without an additional energy source and has a marked targeted therapeutic effect on subcutaneous tumors.

关键词： magnetic Velocity upstream