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Improving cam profile design optimization based on classical splines and dynamic model

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Journal of Central South University 2017年第8期24卷 1817-1825页

作者：夏必忠刘新成尚欣任世远 department of advanced manufacturing Shenzhen Graduate School of Tsinghua UniversityShenzhen 518055China

Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the six order classical spline and single DOF(degree of freedom) dynamic model of single-dwell cam mechanisms is developed. And dynamic constraints such as jumps and vibrations of followers are considered. This optimization model, with many advantages such as universalities of applications, conveniences to operations and good performances in improving kinematic and dynamic properties of cam mechanisms, is good except for the discontinuity of jerks at the end knots of cam profiles which will cause vibrations of cam systems. However, the optimization is improved by combining the six order classical spline with general polynomial spline which is the so-called "trade-offs". Finally, improved optimization is proven to have a better performance in designing cam profiles.

关键词： cam profile design spline optimization trade-off

A Survey of Underwater Multi-Robot Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第1期9卷 1-18页

作者： Ziye Zhou Jincun Liu Junzhi Yu State Key Laboratory for Turbulence and Complex System Department of Advanced Manufacturing and RoboticsBeijing Innovation Center for Engineering Science and Advanced TechnologyCollege of EngineeringPeking UniversityBeijing 100871China College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China

As a cross-cutting field between ocean development and multi-robot system(MRS),the underwater multi-robot system(UMRS)has gained increasing attention from researchers and engineers in recent *** this paper,we present a comprehensive survey of cooperation issues,one of the key components of UMRS,from the perspective of the emergence of new *** specifically,we categorize the cooperation in terms of task-space,motion-space,measurement-space,as well as their ***,we analyze the architecture of UMRS from three aspects,i.e.,the performance of the individual underwater robot,the new functions of underwater robots,and the technical approaches of *** conclude,we have discussed related promising directions for future *** survey provides valuable insight into the reasonable utilization of UMRS to attain diverse underwater tasks in complex ocean application scenarios.

关键词： Cooperation formation control multi-robot systems(MRS) taxonomy underwater robots underwater tasks

Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries

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Nano-Micro Letters 2025年第1期17卷 176-190页

作者： Xiaohong Zou Qian Lu Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and TechnologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China department of Chemistry The Chinese University of Hong KongMa Lin BuildingShatinHong Kong SAR 999077People’s Republic of China WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia Research Institute for advanced manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China

Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe *** is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe *** the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts.

关键词： Catalyst-support interaction Supported catalysts Heterointerface Oxygen evolution reaction Zn-air batteries

Isotope effect on the Casimir force

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Science China(Physics,Mechanics & Astronomy) 2023年第10期66卷 131-137页

作者： Lanyi Xie Fuwei Yang Bai Song department of Energy and Resources Engineering Peking UniversityBejing 100871China Center for Nano and Micro Mechanics Tsinghua UniversityBejing 100084China department of advanced manufacturing and robotics Peking UniversityBejing 100871China Beijing Innovation Center for Engineering Science and advanced Technology Peking UniversityBeijing 100871China

Isotopic dependence of the Casimir force is key to probing new physics and pushing novel technologies at the micro and nanoscale, but is largely unexplored. In 2002, an isotope effect of 10^(-4) was estimated for metals—orders of magnitude beyond the experimental resolution. Here, by employing the Lifshitz theory, we reveal a significant isotope effect of over 10^(-1) for polar dielectrics. This effect arises from the isotope-mass-induced line shift of the zone-center optical phonons and is insensitive to the linewidth. We perform numerical analyses on both the imaginary and real-frequency axes, and derive analytical formulas for predicting the isotope effect. The three-orders-of-magnitude difference between polar dielectrics and metals arises from the distinct isotopic dependence of the phonon and plasma frequencies. Our work opens up a new avenue for engineering forces at small scales and may also facilitate the quest for the fifth force of nature.

关键词： isotope effect Casimir force polar dielectric phonon line shift plasma frequency

Advances in atomic force microscopy for single-cell analysis

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Nano Research 2019年第4期12卷 703-718页

作者： Mi Li Ning Xi Yuechao Wang Lianqing Liu State Key Laboratory of robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China Institutes for robotics and Intelligent manufacturing Chinese Academy of Sciences Shenyang 110016 China department of Industrial and manufacturing Systems Engineering The University of Hong Kong Hong Kong 999077 China

Single-cell analysis has been considered as a promising way to uncover the underlying mechanisms guiding the mysteries of life activities, which con siderably complements traditio nal en semble assays and yields novel in sights into cell biology. The adve nt of atomic force microscopy (AFM) provides a potent tool for investigati ng the structures and properties of n ative biological samples at the micro/na no scale un der near-physiological conditions, which promotes the studies of single-cell behaviors. In the past decades, AFM has achieved great success in single-cell observation and manipulation for biomedical applications, demonstrating the excellent capabilities of AFM in addressing biological issues at the single-cell level with unprecedented spatiotemporal resolution. In this article, we review the recent advances in single-cell analysis that has been made with the utilization of AFM, and provide perspectives for future progression.

关键词： atomic force microscopy single-cell analysis cellular morphology cellular mechanics cellular manipulation

Modeling and simulation of percussive impact for robotic riveting system

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Advances in manufacturing 2014年第4期2卷 344-352页

作者： Shuai Guo Song-Liang Nie Feng-Feng Xi Tao Song Shanghai Key Laboratory of Intelligent manufacturing and robotics Shanghai University department of Aerospace Engineering Ryerson University

Riveting is one of the major joining methods used in assembly, and the robotic riveting has been grad- ually introduced into aircraft industry. In this paper, a method is presented for modeling and simulation of per- cussive robotic riveting. In percussive riveting, vibration always exists. When an impact force is employed, a forced vibration will be induced. If it resonates with a robot nat- ural frequency, the vibration will cause damage to the robot. The main content of this paper is divided into three parts. Firstly, a robot dynamic model is established to compute the driving torque for each joint. Secondly, vibration responses under impact are analyzed for the percussive riveting process. Thirdly, the effect of riveting on robot vibration is studied over the robot workspace. The purpose of this paper is to discuss the suitable regions for riveting where the robot vibration is very minimal. It is shown that based on the presented method an appropriate trajectory can be planned for robotic riveting.

关键词： Robotic dynamics Analysis Vibrationresponse Impact force Riveting

Fabrication of Waterproof Artificial Compound Eyes with Variable Field of View Based on the Bioinspiration from Natural Hierarchical Micro–Nanostructures

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Nano-Micro Letters 2020年第12期12卷 13-28页

作者： Peilin Zhou Haibo Yu Ya Zhong Wuhao Zou Zhidong Wang Lianqing Liu State Key Laboratory of robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016People’s Republic of China Institutes for robotics and Intelligent manufacturing Chinese Academy of SciencesShenyang 110169People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China department of advanced robotics Chiba Institute of TechnologyChiba 275‑0016Japan

Planar and curved microlens arrays(MLAs)are the key components of miniaturized microoptical *** order to meet the requirements for advanced and multipurpose applications in microoptical field,a simple manufacturing method is urgently required for fabricating MLAs with unique properties,such as waterproofness and variable field-of-view(FOV)*** properties are beneficial for the production of advanced artificial compound eyes for the significant applications in complex microcavity environments with high humidity,for instance,miniature medical ***,the simple and effective fabrication of advanced artificial compound eyes still presents significant *** this paper,bioinspired by the natural superhydrophobic surface of lotus leaf,we propose a novel method for the fabrication of waterproof artificial compound *** jet printing was used to fabricate hierarchical MLAs and nanolens arrays(NLAs)on polydimethylsiloxane *** flexible film of MLAs hybridized with NLAs exhibited excellent superhydrophobic property with a water contact angle of 158°.The MLAs film was deformed using a microfluidics chip to create artificial compound eyes with variable FOV,which ranged from 0°to 160°.

关键词： Bioinspired Hierarchical MLAs and NLAs Waterproof artificial compound eyes E-jet printing Microfluidics chip

Vision‐audio fusion SLAM in dynamic environments

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1364-1373页

作者： Tianwei Zhang Huayan Zhang Xiaofei Li Shenzhen Institute of Artificial Intelligence and robotics for Society ShenzhenChina department of robotics Ritsumeikan UniversityShigaJapan Westlake University and Westlake Institute for advanced Study HangzhouChina

Moving humans,agents,and subjects bring many challenges to robot self‐localisation and environment *** adapt to dynamic environments,SLAM researchers typically apply several deep learning image segmentation models to eliminate these moving ***,these moving obstacle segmentation methods cost too much computation resource for the onboard processing of mobile *** the current industrial environment,mobile robot collaboration scenario,the noise of mobile robots could be easily found by on‐board audio‐sensing processors and the direction of sound sources can be effectively acquired by sound source estimation algorithms,but the distance estimation of sound sources is ***,in the field of visual perception,the 3D structure information of the scene is relatively easy to obtain,but the recognition and segmentation of moving objects is more *** address these problems,a novel vision‐audio fusion method that combines sound source localisation methods with a visual SLAM scheme is proposed,thereby eliminating the effect of dynamic obstacles on multi‐agent *** heterogeneous robots experiments in different dynamic scenes indicate very stable self‐localisation and environment reconstruction performance of our method.

关键词： dynamic environment intelligent robots sensor fusion

Velocity Control of a Bounding Quadruped via Energy Control and Vestibular Reflexes

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Journal of Bionic Engineering 2014年第4期11卷 556-571页

作者： Xin Wang Mantian Li Wei Guo Pengfei Wang Lining Sun State Key Laboratory of robotics and System Harbin Institute of Technology Harbin 150001 P. R. China department of advanced robotics (Fondazione) Istituto Italiano di Tecnologia Genova 16163 Italy

In this paper a bio-inspired approach of velocity control for a quadruped robot running with a bounding gait on compliant legs is set up. The dynamic properties ofa sagittal plane model of the robot are investigated. By analyzing the stable fixed points based on Poincare map, we find that the energy change of the system is the main source for forward velocity adjustment. Based on the analysis of the dynamics model of the robot, a new simple linear running controller is proposed using the energy control idea, which requires minimal task level feedback and only controls both the leg torque and ending impact angle. On the other hand, the functions of mammalian vestibular reflexes are discussed, and a reflex map between forward velocity and the pitch movement is built through statistical regression analysis. Finally, a velocity controller based on energy control and vestibular reflexes is built, which has the same structure as the mammalian nervous mechanism for body posture control. The new con- troller allows the robot to run autonomously without any other auxiliary equipment and exhibits good speed adjustment capa- bility. A series simulations and experiments were set to show the good movement agility, and the feasibility and validity of the robot system.

关键词： legged robots biologically-inspired robots biomimetics energy control vestibular reflexes