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Insect Science 2024年第4期31卷 1187-1199页

作者： Haojia Ding shaoze yan State Key Laboratory of Tribology in Advanced Equipment(SKLT) Division of Intelligent and Biomechanical SystemsDepartment of Mechanical EngineeringTsinghua UniversityBeijingChina

Our understanding of the nervous tissues that affect the wing flapping of insects mainly focuses on the brain,but wing flapping is a rhythmic movement related to the central pattern generator in the ventral nerve *** verify whether the neural activity of the abdominal ganglion of the honeybee(Apis mellifera)affects the flapping-wing flight,we profiled the response characteristics of indirect flight muscles to abdominal ganglion ***,a change in the neural activity of ganglion 3 or ganglion 4 has a stronger effect on the electrophysiological activity of indirect flight muscles than that of ganglion *** electrophysiological activity of vertical indirect flight muscles is affected more by the change in neural activity of the abdominal ganglion than that of lateral indirect flight ***,the change in neural activity of the abdominal ganglion mainly causes the change in the muscular activity of indirect wing muscles,but the activity patterns change relatively little and there is little change in the complicated *** work improves our understanding of the neuroregulatory mechanisms associated with the flapping-wing flight of honeybees.

关键词： abdominal ganglion electromyography flapping wing honeybee indirect flight muscle muscular activity

Development of wet adhesion of honeybee arolium incorporated polygonal structure with three-phase composite interfaces

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Friction 2024年第2期12卷 215-230页

作者： Lulu LIANG Jieliang ZHAO Qun NIU Li YU Xiangbing WU Wenzhong WANG shaoze yan Zhenglei YU School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Division of Intelligent and Biomechanical Systems State Key Laboratory of TribologyDepartment of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China

Inspired by the dynamic wet adhesive systems in nature,various artificial adhesive surfaces have been developed but still face different ***,the theoretical mechanics of wet adhesives has never been sufficiently ***,we develop a novel adhesive mechanism for governing wet adhesion and investigate the biological models of honeybee arolium for reproducing the natural wet adhesive ***-nano structures of honeybee arolium and arolium-prints were observed by Cryogenic scanning electron microscopy(Cryo-SEM),and the air pockets were found in the contact interface ***,the adhesive models with a three-phase composite interface(including air pockets,liquid secretion,and hexagonal frames of arolium),were formed to analyze the wet adhesion of honeybee *** results of theoretical calculations and experiments indicated an enhanced adhesive mechanism of the honeybee by liquid self-sucking effects and air-embolism *** these effects,normal and shear adhesion can be adjusted by controlling the proportion of liquid secretion and air pockets in the contact ***,the air-embolism effects contribute to the optimal coupling of smaller normal adhesion with greater shear adhesion,which is beneficial for the high stride frequency of *** works can provide a fresh perspective on the development of bio-inspired wet adhesive surfaces.

关键词： honeybee arolium air pockets wet adhesion a three-phase interface self-sucking effects air-embolism effects

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考虑尺度的结合面切向刚度模型

机械工程学报 2024年第3期60卷 181-190页

作者：罗治军阎绍泽田桂清华大学机械工程系北京100084 中国人民解放军96963部队博士创新工作站北京100084 陆军航空兵学院航电和兵器工程系北京101123

接触刚度是结合面特性中最重要的参数之一,直接影响着机械结构整体的动力学特性。GW(Greenwood&Williamson)模型是目前被广泛应用的结合面接触模型,在许多实验中取得了较好的预测结果。理论上,GW模型预测结果受仪器分辨率影响,预测值并... 详细信息

接触刚度是结合面特性中最重要的参数之一,直接影响着机械结构整体的动力学特性。GW(Greenwood&Williamson)模型是目前被广泛应用的结合面接触模型,在许多实验中取得了较好的预测结果。理论上,GW模型预测结果受仪器分辨率影响,预测值并不唯一,但是实验得到的宏观物理量如刚度、导电率等却是唯一值。这一矛盾说明,存在一个唯一的计算或者观测尺度以确保宏观结果的唯一性。理论上分析了GW模型的尺度依赖特性;研究了采用高斯滤波器实现计算尺度变换的方法;基于Thomas的接触理论,设计了确定滤波器截止频率的迭代方法;最终提出了一种考虑尺度的结合面切向刚度计算框架。搭建了切向刚度试验台,对考虑尺度的切向刚度模型进行验证。结果表明,考虑尺度的模型与实验结果吻合较好。

关键词：真实接触面接触模型尺度依赖 GW模型 MB模型

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变体飞行器头锥的运动控制性能分析

振动．测试与诊断 2024年第2期44卷 345-352,413页

作者：田静怡张玉玲尹丹妮谷勇霞阎绍泽北京工商大学计算机与人工智能学院北京100048 清华大学机械工程系北京100084

为提高变体飞行器头锥在外部负载条件下的运动性能,提出一种二自由度的3RSH/3RRR变体头锥机构(R,S,H分别为转动副、球副及螺旋副),进行了位置分析和机构运动特性分析。通过Simulink/SimMechanics工具箱搭建变体头锥机构框图,并分别搭建... 详细信息

为提高变体飞行器头锥在外部负载条件下的运动性能,提出一种二自由度的3RSH/3RRR变体头锥机构(R,S,H分别为转动副、球副及螺旋副),进行了位置分析和机构运动特性分析。通过Simulink/SimMechanics工具箱搭建变体头锥机构框图,并分别搭建模糊比例积分微分(proportion integration differentiation,简称PID)控制系统和BP神经网络(backpropagation networks,简称BPNN)PID控制系统。在空载、随机变化负载2种不同外部环境下,设定阶跃、正弦2种期望轨迹进行仿真,比较了常规PID、模糊PID和神经网络PID的控制性能。实验结果表明,智能控制的适应性、鲁棒性远好于常规PID,其中模糊PID控制对变体头锥机构的控制性能最好,能够满足不同工况下的控制要求。

关键词：变体头锥机构运动性能控制策略控制性能

Experimental investigations on structural improvement of morphing mechanism for nose cone of aerospace vehicle adopting a bionic redundant constraint strategy

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Science China(Technological Sciences) 2023年第4期66卷 1075-1095页

作者： ZHANG YuLing LI ChengXiang ZHANG yan CAI Qiaoyan yan shaoze Division of Intelligent and Biomechanical Systems State Key Laboratory of Tribology in Advanced EquipmentDepartment of Mechanical EngineeringTsinghua UniversityBeijing 100084China China Academy of Launch Vehicle Technology Beijing 100071China

Aerospace vehicles have recently received great attention for their completely reusable in aviation and *** achieve the optimal aerodynamic performance of the aerospace vehicle,the nose cone needs to change its aerodynamic shape under different flight ***,the structural design of a morphing nose cone that is capable of changing aerodynamic shape adaptively and withstanding prescribed aerodynamic loads remains an ongoing *** overcome this issue and to further advance our previous work,the motion performance of a morphing nose cone inspired by the deformation mechanism of the honeybee abdomen was tested to evaluate the deformation ability and bearing *** dynamic prediction analysis of the morphing nose cone with a clearance joint and flexible links was then investigated to elucidate the crucial issues in the deformation *** improve the motion performance,a performance improvement scheme based on redundant constraints drawn from the muscle distribution of the honeybee abdomen was ***,the structural stiffness,dynamic analysis,and experimental testing of the improved morphing nose cone were *** experimental results indicate that the extension and contraction ratios and bending angles of the improved morphing nose cone under loads of 0,10,and 25 kg loads improve by 1.51%and 2.329°,2.78%and-1.902°,and 5.06%and 1.111°,respectively,verifying the rationality and effectiveness of the performance improvement *** work provides a new reference for the design of the morphing structure for aerospace vehicles.

关键词： morphing nose cone experimental investigation dynamic analysis performance improvement bionic design

Experimental Verification on Steering Flight of Honeybee by Electrical Stimulation

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Cyborg and Bionic Systems 2022年第1期2022卷 347-358页

作者： Li Yu Jieliang Zhao Zhiyun Ma Wenzhong Wang shaoze yan Yue Jin Yu Fang School of Mechanical Engineering Beiing Institute of Technology Beijing 100081China Division of Iteligent and Biomechanical Systems State Key Laboratory of TribologyDepartment of Mechanical Engineering Tsinghua UniversityBejing 100084China Institute of Apicultural Research Chinese Academy of Agricultural Scince100193China

The artificial locomotion control strategy is the fundamental technique to ensure the accomplishment of the preset assignments for cyborg *** existing research has recognized that the electrical stimulation applied to the optic lobes was an appropriate flight control strategy for small insedts represented by *** control technique has been confirmed to be effective for honeybee flight initiation and ***,its regulation effect on steering locomotion has not been fully ***,we investigated the steering control effect of honeybee by applying electrical stimulation signals with different duty cycles and frequencies on the unilateral optic lobes and screened the stimulus parameters with the highest response successful ***,we confirmed the effectiveness of steering control by verifying the presence of rotation torque on tethered honeybees and the body orientation change of crawling *** study will contribute some reliable parameter references to the motion control of cyborg honeybees.

关键词： fir effect accomplishment

Honeybees have Hydrophobic Wings that Enable Them to Fly through Fog and Dew

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Journal of Bionic Engineering 2017年第3期14卷 549-556页

作者： Youjian Liang Jieliang Zhao shaoze yan Division of Intelligent and Biomechanical Systems State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Honeybees have received public attention for their remarkable performance in low-altitude flying and their outstanding airborne hovering capability. However, minimal attention has been given to their capability to fly through the harshest climatic conditions. In this study, we used a high-speed camera and recorded an interesting phenomenon in which honeybees （Apis mellifera ligustica） flew effortlessly through mists or drizzling rain. To identify the mechanism behind honeybees flying through mists, the microstructure of their wings was examined via atomic force microscopy and scanning electron microscopy. Ex- perimental results showed that the surface of a honeybee wing was rough, with bristles distributed on both the dorsal and ventral sides. The measurement results of the contact angle proved that the surface of honeybee wings was hydrophobie. Furthermore, hydrophobic proteins, which contained at least one hydrophobic tetra-peptide （i.e., AAPA/V）, were obtained. The rugged sur- face and hydrophobic proteins caused the hydrophobicity of honeybee wings. These results identify the hydrophobic mechanism of honeybee wings, which will be useful in designing hydrophobic structures.

关键词： hydrophobicity microstructure biological coupling hydrophobic peptide honeybee wing

A comprehensive method for joint wear prediction in planar mechanical systems with clearances considering complex contact conditions

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Science China(Technological Sciences) 2015年第1期58卷 86-96页

作者： XIANG WuWeiKai yan shaoze WU JiaNing State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University

A comprehensive method to predict wear in planar mechanical systems with clearance joints is presented and discussed in this *** method consists of a system dynamic analysis and a joint wear *** the size and shape of the clearance are dictated by wear and evolve with the dynamic response of the system,the contact between the journal and bearing could be conformal or non-conformal,which makes the contact conditions in clearance joints quite *** a modified contact force model is employed to evaluate the joint reaction force in this *** the nonlinear stiffness coefficient is related to the physical and geometrical properties of contact bodies and varies with the deformation,this contact force model is applicable to different contact conditions between the journal and ***,based on the Archard’s wear model,the amount of wear can be quantified in the *** the geometry is updated to reflect the evolving contact ***,the wear process and the contact force model are integrated into the motion equations of the system to perform coupled iterative analyses between system dynamic response and joint wear *** addition,a slider-crank mechanism is simulated as an example to demonstrate efficiency of the proposed method and to carry out a parametric study on mechanical systems considering joint *** influence of clearance size and driving power are discussed and compared *** index of concordance is introduced to quantify contributions of contact pressure and sliding distance to wear rate under different types of journal *** study could help to predict joint wear in mechanical systems with clearances and optimize mechanisms in design.

关键词：关节间隙磨损预测机械系统接触条件平面曲柄滑块机构动态响应几何形状

A method for detection and quantification of meshing characteristics of harmonic drive gears using computer vision

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Science China(Technological Sciences) 2016年第9期59卷 1305-1319页

作者： MA DongHui WU JiaNing yan shaoze State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University

A lack of accurate description of the meshing characteristics and the corresponding frictional mechanism of the harmonic drive gear has limited progress toward modeling the hysteresis stiffness. This paper presents a method for detection and quantification of the meshing characteristics of the harmonic drive gear based on computer vision. First, an experimental set-up that integrates a high speed camera system with a lighting system is developed, and the image processing is adopted to extract and polish the tooth profiles of the meshed teeth pairs in each acquired video sequence. Next, a physical-mathematical model is established to determine the relative positions of the selected tooth pair in the process of the gear engagement, and the combined standard uncertainty is utilized to evaluate the accuracy of the calculated kinematics parameters. Last, the kinematics analysis of the gear engagement under the ultra-low speed condition is performed with our method and previous method, and the influence of the input rotational speed on the results is examined. The results validate the effectiveness of our method, and indicate that the conventional method is not available in the future friction analysis. It is also shown that the engaging-in phase is approximately a uniform motion process, the engaging-out phase is a variable motion process, and these characteristics remain unchanged with the variation of the input rotational speed. Our method affords the ability to understand the frictional mechanism on the meshed contact surfaces of the harmonic drive gear, and also allows for the dynamic monitoring of the meshing properties.

关键词：计算机视觉检测谐波齿轮传动啮合特性合成标准不确定度高速摄像系统视频图像序列物理数学模型齿轮传动机构

The Morphology and Reciprocation Movement of Honeybee＇s Hairy Tongue for Nectar Uptake

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Journal of Bionic Engineering 2016年第1期13卷 98-107页

作者： Yiwei Zhao Jianing Wu Heng yang shaoze yan Division of Intelligent and Biomeehanical Systems State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Automotive Engineering Tsinghua University Beijing 100084 China

A honeybee uses its brush-like tongue （glossa） to dip nectar and the setae densely distributed on it can increase the amount of trapped nectar observably. The glossa is often simplified as a cylinder covered by uniformly distributed and vertically erected setae during the drinking process, herein variations of the dimensions together with the erection angles of glossal setae are assumed to be negligible. In this paper, a dynamic model for the glossa retraction phase under the specific erection pattern of glossal setae is established, and the energy saving mechanism is extensively studied by comparing four types of erection pat- terns. Then the theoretically-optimal configuration, which satisfies the minimum energy consumption, is achieved from the dynamic model. Using the scanning electron microscope and a specially-designed high-speed camera system, we measure the dimensions of the glossal satae and capture dynamics of the hairy glossa in nectar feeding. It is proven that the erection angle of the glossal setae varies along the tongue axis, which shows a high concordance with our theoretically-optimal configuration. Compared with the hypothetical uniform distribution mode of glossal setae proposed by former researchers, we obtain a 16% increase in energy saving from actual erection pattern.

关键词： honeybee hairy tongue glossal setae dimensional distribution erection pattern