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A Magnetic-Driven Multi-motion Robot with Position/Orientation Sensing Capability

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Research 2024年第1期2023卷 675-685页

作者： Liwen zhang Song Zhao Xinzhao Zhou Xueshan Jing Yu Zhou Yan Wang Yantong Zhu Xiaolin Liu Zehui Zhao deyuan zhang Lin Feng Huawei Chen School of Mechanical Engineering and Automation Beihang UniversityBeijingChina Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijingChina

Miniature magnetic-driven robots with multimode motions and high-precision pose sensing capacity(position and orientation)are greatly demanded in in situ manipulation in narrow opaque enclosed spaces.Various magnetic robots have been carried out,whereas their deformations normally remain in single mode,and the lack of the robot’s real-time status leads to its beyond-sight remagnetization and manipulation being impossible.The function integration of pose sensing and multimode motion is still of challenge.Here,a multimotion thin-film robot is created in a novel multilayer structure with a magneticdriven layer covered by a heating-sensing conductive layer.Such a heating-sensing layer not only can segmentally and on-demand heat the magnetic-driven layer for in situ magnetization reprogramming and multimode motions but also can precisely detect the robot’s pose(position and orientation)from its electrical-resistance effect by creating a small deformation under preset magnetic fields.

关键词： robot Robot motion

High-efficiency ultrasonic assisted drilling of CFRP/Ti stacks under non-separation type and dry conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 275-291页

作者： Enze YING Zehua ZHOU Daxi GENG Zhenyu SHAO Zhefei SUN Yihang LIU Lianxing LIU Xinggang JIANG deyuan zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing Chenjing Electronics Company Limited Beijing 100015China Aerospace Times Feihong Technology Company Limited Beijing 100094China

In this study,to address the low efficiency for conventional ultrasonic-assisted drlling(UAD)of carbon fiber-reinforced plastic and titanium alloy(CFRP/Ti)stacks,feasibility experiments of non-separation UAD,in which continuous cutting between the tool and the workpiece occurs at a high feed rate,are carried out.The experimental results indicate that,compared to conventional separation UAD,the non-separation UAD effectively reduces the cutting forces by 24.2%and 1.9%for CFRP stage and 22.1%and 2.6%for the Ti stage at the feed rates of 50 and 70μm/r,respectively.Furthermore,the non-separation UAD significantly improves hole quality,including higher hole diameter accuracy,lower hole surface roughness,and less hole damage.In addition,the non-separation UAD can decrease adhesive tool wear.This study demonstrates that,compared to conventional drilling(CD),the non-separation UAD can effectively improve drilling quality and tool life while maintaining high efficiency.

关键词： Carbon fiber-reinforced plastic and titanium alloy(CFRP/Ti)stacks Ultrasonic-assisted drlling(UAD) Cutting force Surface integrity Tool wear

Segment-wise learning control for trajectory tracking of robot manipulators under iteration-dependent periods

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Science China(Information Sciences) 2024年第3期67卷 155-166页

作者： Fan zhang deyuan MENG Kaiquan CAI The Seventh Research Division Beihang University School of Automation Science and Electrical Engineering Beihang University School of Electronics and Information Engineering Beihang University

This paper is concerned with the amplitude boundedness problem of adaptive iterative learning control(AILC) for robot manipulators operating with iteration-dependent periods. By introducing virtual memory slots for storing historical data, a practical AILC method is proposed to achieve the segmentwise learning. This method requires less memory storage for historical information of previous iterations,especially in comparison with that of the conventional AILC methods using point-wise learning strategies.It is shown that not only the energy boundedness but also the amplitude boundedness of estimates and inputs of practical AILC can be guaranteed. Moreover, the practical AILC method can achieve the perfect tracking objective regardless of iteration-dependent periods when the robot manipulators have a persistent full learning property. In addition, a solution to the visual manipulator platform is provided and deployed based on Coppeliasim and Matlab, which helps to show the amplitude boundedness of learning results and the perfect tracking performances of the proposed practical AILC method for robot manipulators.

关键词： amplitude boundedness iteration-dependent period iterative learning control robot manipulator segment-wise virtual memory slot

Bioinspired Functional Surfaces for Medical Devices

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 37-50页

作者： Liwen zhang Guang Liu Yurun Guo Yan Wang deyuan zhang Huawei Chen School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China

Medical devices are a major component of precision medicine and play a key role in medical treatment,particularly with the rapid development of minimally invasive surgery and wearable devices.Their tissue contact properties strongly affect device performance and patient health(e.g.,heat coagulation and slipperiness on surgical graspers).However,the design and optimization of these device surfaces are still indistinct and have no supporting principles.Under such conditions,natural surfaces with various unique functions can provide solutions.This review summarizes the current progress in natural functional surfaces for medical devices,including ultra-slipperiness and strong wet attachment.The underlying mechanisms of these surfaces are attributed to their coupling effects and featured micronano structures.Depending on various medical requirements,adaptable designs and fabrication methods have been developed.Additionally,various medical device surfaces have been validated to achieve enhanced contact properties.Based on these studies,a more promising future for medical devices can be achieved for enhanced precision medicine and human health.

关键词： Bioinspired functional surfaces Medical devices Wet attachment Interfacial liquid Micro-nano structures Wearable devices

Manipulating Nanowires in Interconnecting Layer for Efficient Tandem Organic Photovoltaics

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Chinese Journal of Chemistry 2024年第4期42卷 377-383页

作者： Yanjie Tang Jiaming Fu Hao Li Du Hyeon Ryu Won Suk Shin Jianqi zhang Yi Yang Yiming Yang deyuan Li Zhong Zheng Shaoqing zhang Jianhui Hou School of Chemistry and Biology Engineering University of Science and Technology Beijing(USTB)Beijing100083 China State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of Sciences(ICCAS)Beijing100190 China Energy Materials Research Center Korea Research Institute of Chemical Technology(KRICT)Advanced Materials&Chemical EngineeringUniversity of Science&Technology(UST)Korea The National Center for Nanoscience and Technology(NCNST) Beijing100190 China University of Chinese Academy of Sciences Beijing(UCAS) Beijing100049 China China Railway Resources Group Survey and Design Co.Ltd. LangfangHebei065000 China

Owing to the function of manipulating light absorption distribution,tandem organic solar cells containing multiple sub-cells exhibit high power conversion efficiencies.However,there is a substantial challenge in precisely controlling the inter-subcells carrier migration which determines the balance of charge transport across the entire device.The conductivity of"nanowires"-like conducting channel in interconnecting layer between sub-cells should be improved which calls for fine engineering on the morphology of polyelectrolyte in interconnecting layer.Here,we develop a simple method to effectively manipulating the domains of conductive components in commercially available polyelectrolyte PEDOT:PSs.The use of poor solvent could effectively modify the configuration of polystyrene sulfonic acid and thus the space for conductive components.Based on our strategy,the insulated shells wrapping conductive domains are thinned and the efficiencies of tandem organic solar cells are improved.We believe our method might provide guidance for the manufacture of tandem organic solar cells.

关键词： Tandem organic solar cells Power conversion efficiency interconnecting layer Tunneling junction Interfacial layers Conformationanalysis π-πstacking Donor-acceptorsystems

Bio-inspired Flexible Airflow Sensor with Self-bended 3D Hair-like Configurations

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Journal of Bionic Engineering 2022年第1期19卷 73-82页

作者： Dawei Shen Yonggang Jiang Zhiqiang Ma Peng Zhao Zheng Gong Zihao Dong deyuan zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China International Research Institute of Multidisciplinary Science Beihang UniversityBeijing100191China

This paper presents a novel flexible airflow sensor based on four curved microcantilevers arranged in a cross-form configuration.A self-bending method based on MEMS technology has been used to fabricate the curved microcantilevers structure,and this method can transfer a 2D plane structure into a 3D structure with good consistency in the morphology.The curved microcantilever consists of a polyimide(PI)top layer,silicon(Si)bottom layer,and platinum(Pt)piezoresistor at the root of the cantilever.The difference in the in-plane residual stress between the PI and Si layers bent the microcantilever upward.The curved-up microcantilever transfers the fluidic momentum that acts on it to drag force,which deflects the curved-up microcantilever and changes the resistance of the piezoresistor.To realize temperature compensation and decrease the noise,a reference resistor and an ambient temperature detector were integrated for the Wheatstone half-bridge measurement and temperature monitoring,respectively.The cross-form configuration of the curved-up cantilevers has high sensitivity advantages and possesses direction-sensing ability.Experimental results show that the sensitivity of the sensors increased as a function of the airflow velocity,and the sensors exhibited a maximum resolution of 4 mm⋅s^(−1) and a maximum sensitivity of 60.35 mV⋅(ms^(−1))^(−1) when the airflow velocity was larger than 38.5 m⋅s^(−1).

关键词： Airflow sensor Piezoresistive Self-bended cantilevers Flexible sensor

Ironing effect on surface integrity and fatigue behavior during ultrasonic peening drilling of Ti-6Al-4V

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Chinese Journal of Aeronautics 2023年第5期36卷 486-498页

作者： Yihang LIU deyuan zhang Daxi GENG Zhenyu SHAO Zehua ZHOU Zhefei SUN Yonggang JIANG Xinggang JIANG School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Institute of Bionic and Micro-Nano Systems Beihang UniversityBeijing 100191China Aerospace Times Feihong Technology Company Limited Beijing 100094China

Imposing compressive residual stress field around a fastening hole serves as a universal method to enhance the hole fatigue strength in the aircraft assembly filed.Ultrasonic Peening Drilling(UPD)is a recently proposed hybrid hole making process,which can achieve an integration of strengthening and precision-machining with a one-shot-drilling operation.Due to the ironing effect of tool flank surface,UPD introduces large compressive residual stress filed in hole subsurface.In order to reveal the strengthening mechanism of UPD,the influence of ultrasonic vibration and tool dynamic relief angle on ironing coverage rate and its corresponding effect on surface integrity in UPD were analyzed.The experiments were conducted to verify the influence of ironing effect on surface integrity and fatigue behavior of Ti-6Al-4V hole in UPD.The results indicate that the specimen features smaller surface roughness,higher micro-hardness,plastic deformation degree and circumferential compress residual stress under higher ironing coverage rate.The fatigue life increases with the raise of ironing coverage rate,and the fatigue source site in UPD shifts from surface to subsurface comparing with that without vibration assistance.The results demonstrates that a better strengthening effect can be obtained by reasonably controlling the ironing coverage rate in UPD.

关键词： Fatigue strength Surface integrity Titanium alloy Tool relief angle Ultrasonic Peening Drilling(UPD)

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超声纵扭-低频扭转复合振动攻丝实验

北京航空航天大学学报 2024年第4期50卷 1077-1084页

作者：韩凤起张德远河北工业职业技术大学智能制造学院石家庄050091 北京航空航天大学机械工程及自动化学院北京100191

针对钛合金低频扭转振动攻丝效率偏低的问题,提出了超声纵扭-低频扭转复合振动攻丝方法。进行了超声纵扭振动攻丝实验、不同切削液的复合振功攻丝实验和变参数复合振动攻丝实验,研究复合振动攻丝的工艺效果及参数变化的影响规律。实验... 详细信息

针对钛合金低频扭转振动攻丝效率偏低的问题,提出了超声纵扭-低频扭转复合振动攻丝方法。进行了超声纵扭振动攻丝实验、不同切削液的复合振功攻丝实验和变参数复合振动攻丝实验,研究复合振动攻丝的工艺效果及参数变化的影响规律。实验结果表明:超声纵扭振动增强了切削液的润滑效果,降低了攻丝扭矩,与普通连续攻丝相比,M3螺纹孔的超声纵扭振动攻丝可降低攻丝扭矩约18%;在所选参数范围内,与低频扭转振动攻丝相比,复合振动攻丝最大可降低攻丝扭矩约30%;复合振动攻丝降低攻丝扭矩的效果,随净切削量、主轴转速的增大和回退量的减小而降低。

关键词：振动攻丝超声纵扭振动低频扭转振动攻丝扭矩切削液润滑

Chatter stability and precision during high-speed ultrasonic vibration cutting of a thin-walled titanium cylinder

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Chinese Journal of Aeronautics 2020年第12期33卷 3535-3549页

作者： Zhenlong PENG deyuan zhang Xiangyu zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China Institute of Bionic and Micro-Nano Systems Beihang UniversityBeijing 100083China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100083China

Titanium alloys are widely used in the aviation and aerospace industries due to their unique mechanical and physical properties.Specifically,thin-walled titanium(Ti)cylinders have received increasing attention for their applications as rocket engine casings,aircraft landing gear,and aero-engine hollow shaft due to their observed improvement in the thrust-to-weight ratio.However,the conventional cutting(CC)process is not appropriate for thin-walled Ti cylinders due to its low thermal conductivity,high strength,and low stiffness.Instead,high-speed ultrasonic vibration cutting(HUVC)assisted processing has recently proved highly effective for Ti-alloy machining.In this study,HUVC technology is employed to perform external turning of a thinwalled Ti cylinder,which represents a new application of HUVC.First,the kinematics,tool path,and dynamic cutting thickness of HUVC are evaluated.Second,the phenomenon of mode-coupling chatter is analyzed to determine the effects and mechanism of HUVC by establishing a critical cutting thickness model.HUVC can increase the critical cutting thickness and effectively reduce the average cutting force,thus reducing the energy intake of the system.Finally,comparison experiments are conducted between HUVC and CC processes.The results indicate that the diameter error rate is 10%or less for HUVC and 51%for the CC method due to a 40%reduction in the cutting force.In addition,higher machining precision and better surface roughness are achieved during thin-walled Ti cylinder manufacturing using HUVC.

关键词： High-speed machining Minimum chip thickness Mode-coupling Thin-walled cylinder Ultrasonic vibration cutting