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Variable-model SMA-driven spherical robot

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Science China(Technological Sciences) 2019年第8期62卷 1401-1411页

作者： pan jie SHI ZhenYun WANG TianMiao Robotic Laboratory Beihang University

In this paper, we introduce a bionic spherical robot. This research has been inspired by the muscular organs and modularity of organisms such as starfish and octopuses. The robot that we fabricated uses five soft feet to crawl like a starfish, and the robotic feet are driven by the shape memory alloy springs. The robotic spherical structure and the soft feet were fabricated by 3 D printing. The robotic feet were made of silicone gel;these feet could bend upward and downward to help the robot to crawl on the ground and roll down a slope. The shell separation module installed inside the robot could divide the robot into two identical modules, and this smart structure could enhance the robotic flexibility in a small space. We performed force analysis and robotic simulation, and the results verified the feasibility of the model. The robot can switch between rigidity and softness by using human control. Three types of gaits have been proposed for controlling robotic movement and improving robotic flexibility in movement;these include rolling, crawling, and avoiding obstacles. The results of this study indicate that the variable-model design of the robot is an effective way to enhance the flexibility of soft robots.

关键词： bionic robot soft animals shape memory alloy smart structure variable model

A novel shape memory alloy actuated soft gripper imitated hand behavior

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Frontiers of Mechanical Engineering 2022年第4期17卷 261-272页

作者： jie pan Jingjun YU Xu PEI School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China

The limited length shrinkage of shape memory alloy(SMA)wire seriously limits the motion range of SMA-based *** this paper,a new soft finger without silicone gel was designed based on pre bent SMA wire,and the finger was back to its original shape by heating SMA wire,rather than relying only on heat exchange with the *** imitating palm movement,a structure with adjustable spacing between fingers was made using SMA spring and rigid *** hook structure design at the fingertip can form self-locking to further improve the load capacity of *** the long thin rod model,the relationship of the initial pre bent angle on the bending angle and output force of the finger was *** stress-strain model of SMA spring was established for the selection of rigid *** grasping modes were proposed to adapt to the weight of the *** the test of the gripper,it was proved that the gripper had large bending amplitude,bending force,and response *** design provides a new idea for the lightweight design and convenient design of soft gripper based on SMA.

关键词： shape memory alloy(SMA) pre bent wire gripper grasping mode lightweight

High-throughput screening of critical size of grain growth in gradient structured nickel

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Journal of Materials Science & Technology 2021年第23期82卷 33-39页

作者： Yunli Lu Fenghui Duan jie pan Yi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

Nanocrystalline metals with high Gibbs free energy have a strong tendency towards thermally driven grain growth,thus understanding the critical size or temperature of grain growth is vital for their *** investigations of thermal stability were usually conducted on the materials with a homogeneous structure;however,these methods are time-consuming and *** the present work,we reveal a high-throughput experimental strategy to characterize the size-dependent thermal stability via annealing the gradient structured *** this method,the critical size of grain growth(d_(c))at a given annealing temperature was rapidly *** critical size of grain growth was~95 nm when annealed at 503 K for 3 h,which is consistent with the value reported in the homogeneous structured ***,this critical size was found to be identical in three types of gradient structured Ni,i.e.,independent on the gradient *** present work demonstrates a high-throughput strategy for exploring the critical size of grain growth and size-dependent thermal stability of metals.

关键词： High-throughput Gradient structure Critical size Grain growth Thermal stablitiy

Diophantine equations and Fermat's last theorem for multivariate(skew-)polynomials

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 159-173页

作者： pan jie JIA Yu-ming LI Fang School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China Henan Experimental High School Zhengzhou 450003China

Fermat’s Last Theorem is a famous theorem in number theory which is diﬃcult to ***,it is known that the version of polynomials with one variable of Fermat’s Last Theorem over C can be proved very *** aim of this paper is to study the similar problems about Fermat’s Last Theorem for multivariate(skew)-polynomials with any characteristic.

关键词： Fermat's last theorem polynomial ring skew polynomial ring

A novel obstacle avoidance heuristic algorithm of continuum robot based on FABRIK

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Science China(Technological Sciences) 2022年第12期65卷 2952-2966页

作者： WU HaoRan YU JingJun pan jie PEI Xu Robotics Institute Beihang UniversityBeijing 100191China Department of Mechanical Design Beihang UniversityBeijing 100191China

Obstacle avoidance and path planning of continuum robots are challenging tasks due to the hyper-redundant degree of freedoms(DOFs)and restricted working ***,most current heuristic algorithm-based obstacle avoidance algorithms exist with low computational efficiency,complex solution process,and inability to add global *** paper proposes a novel obstacle avoidance heuristic algorithm based on the forward and backward reaching inverse kinematics(FABRIK)*** update of key nodes in this algorithm is modeled as the movement of charges in an electric field,avoiding complex nonlinear *** algorithm achieves the robustness of inverse kinematics and path tracking in complex environments by imposing constraints on key nodes and determining the location of obstacles in *** algorithm is characterized by a high convergence rate,low computational cost,and can be used for real-time *** proposed approach also has wide applicability and can be applied to both mobile and fixed-base continuum *** it can be further extended to the field of hyper-redundant *** algorithm's effectiveness is further validated by simulating the path tracking and obstacle avoidance of a five-segment continuum robot in various environments and comparisons with classical methods.

关键词： continuum robot FABRIK algorithm obstacle avoidance motion planning

Two novel resin glycosides isolated from Ipomoea cairica with α-glucosidase inhibitory activity

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Chinese Journal of Natural Medicines 2016年第3期14卷 227-231页

作者： LI jie-Hong pan jie-Tao YIN Yong-Qin Department of Traditional Chinese Medicinal Chemistry Guangdong Pharmaceutical University

In the present study, two new compounds from Ipomoea cairica were identified and demonstrated to have a-glucosidase inhibitory activity. They were isolated by column chromatography on silica gel and sephadex LH-20 and finally purified by prep-HPLC, with their structures being elucidated by spectroscopic methods, such as 1D- and 2D-NMR and HR-TOF-MS, and chemical methods. Compounds 1 and 2, named cairicoside A and cairicoside B, were evaluated for a-glucosidase inhibitory activity by the MTT method, with the ICs0 values being 25.3 ± 1.6 and 28.5± 3.3 μmol·L-1, respectively.

关键词： Ipomoea cairica Resin glycoside Simonic acid A a-Glucosidase

Intelligent self-assembly prodrug micelles loading doxorubicin in response to tumor microenvironment for targeted tumors therapy

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Chinese Journal of Chemical Engineering 2021年第11期34卷 219-227页

作者： Dong Wan Sunfan Li Jianxin Zhang Guilei Ma jie pan School of Chemistry and Chemical Engineering Tiangong UniversityTianjin 300387China The Tianjin Key Laboratory of Biomaterials Institute of Biomedical EngineeringPeking Union Medical College&Chinese Academy of Medical SciencesTianjin 300192China

Compared with physical drug-loaded nanocarriers,polymeric prodrug micelles have many advantages such as high drug loading and enhanced stability in blood,so they have great potential in cancer ***,these micelles have a big disadvantage,which cannot achieve long-term circulation in vivo and high absorption of tumor cells simultaneously,resulting in low administration efficiency and poor therapeutic effect on *** solve problems of traditional polymeric prodrug micelles,novel polymeric micelles with tumor microenvironment response were designed in this *** prodrug formed by covalently linking D-α-tocopherol polyethylene glycol succinate(TPGS_(3350)),peptide(Pep),and doxorubicin(DOX)(TPGS_(3350)-Pep-DOX)was self-assembled into micelles by encapsulating DOX *** the micelles entered the tumor tissue,the long-chain polyethylene glycol(PEG)was sensitively cut by the matrix metalloproteinase 2/9(MMP2/9)enzyme,exposing the targeting molecule folate,then it entered the cell through the endocytic pathway mediated by the folate *** drug loading content,encapsulation efficiency,critical micelle concentration,and invitro release of the micelles invented in this study were measured to characterize their *** particle size and zeta potential of micelles were characterized by dynamic light *** were scanned by transmission electron *** vitro cytotoxicity,cellular uptake,and in vivo antitumor effect evaluation experiments were measured to show that smart micelles have made much progress in material chemistry and drug delivery,making it possible to apply a stimulus-response carrier drug delivery system in clinical application.

关键词： Micelles Drug delivery Tumor Enzyme Polymers Peptide

A survey of the pursuit-evasion problem in swarm intelligence

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Frontiers of Information Technology & Electronic Engineering 2023年第8期24卷 1093-1116页

作者： Zhenxin MU jie pan Ziye ZHOU Junzhi YU Lu CAO State Key Laboratory for Turbulence and Complex Systems Department of Advanced Manufacturing and RoboticsCollege of EngineeringPeking UniversityBeijing 100871China National Innovation Institute of Defense Technology Beijing 100071China

For complex functions to emerge in artificial systems,it is important to understand the intrinsic mechanisms of biological swarm behaviors in *** this paper,we present a comprehensive survey of pursuit–evasion,which is a critical problem in biological ***,we review the problem of pursuit–evasion from three different perspectives:game theory,control theory and artificial intelligence,and bio-inspired *** we provide an overview of the research on pursuit–evasion problems in biological systems and artificial *** summarize predator pursuit behavior and prey evasion behavior as predator–prey ***,we analyze the application of pursuit–evasion in artificial systems from three perspectives,i.e.,strong pursuer group *** evader group,weak pursuer group *** evader group,and equal-ability ***,relevant prospects for future pursuit–evasion challenges are *** survey provides new insights into the design of multi-agent and multi-robot systems to complete complex hunting tasks in uncertain dynamic scenarios.

关键词： Swarm behavior Pursuit-evasion Artificial systems Biological model Collective motion

Toughening additive manufactured Zr-based bulk metallic glass composites by martensite phase transformation

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Journal of Materials Science & Technology 2024年第3期170卷 95-102页

作者： Pengcheng Zhang Cheng Zhang jie pan Di Ouyang Lin Liu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Additive manufacturing technology based on laser powder bed fusion(LPBF)offers a novel approach for fabricating bulk metallic glass(BMG)products without restriction in size and ***,the BMGs prepared by LPBF usually suffered from less plasticity and poorer fracture toughness as compared to their cast counterparts due to partial crystallization in heat-affected zones(HAZs).Since crystallization in HAZs is hard to avoid completely in LPBF BMGs,it is desirable to design a suitable alloy system,in which only ductile crystalline phase,instead of brittle intermetallics,is formed in *** unique structure could effectively increase the toughness/plasticity of the LPBF *** achieve this goal,a quaternary BMG system with a composition of Zr_(47.5)Cu_(45.5)Al_(5)Co_(2)is adopted and subjected to *** is found that nearly a single phase of B_(2)-ZrCu is precipitated in HAZs,while a fully amorphous phase is formed in molten pools(MPs).This B_(2)phase reinforced BMG composite exhibits excellent mechanical properties with enhanced plasticity and ***,it is easy to modulate the mechanical properties by altering the amount of the B_(2)phase via adjusting the laser energy ***,the best combination of strength,plasticity,and notch toughness is obtained in the BMG composite containing 27.4%B_(2)phase and 72.6%amorphous phase,which exhibits yield strength(σ_(s))of 1423 MPa,plastic strain(ε_(p))of 4.65%,and notch toughness(K_(q))of 53.9 MPa m 1/***,a notable strain-hardening is also *** improvement of plasticity/toughness and appearance of strain-hardening behavior are mainly due to the martensite phase transformation from the B_(2)phase to the Cm phase during plastic deformation(i.e.,the phase transformation-induced plasticity effect).The current work provides a guide for making advanced BMGs and BMG composites by additive manufacturing.

关键词： Laser powder bed fusion Bulk metallic glass composites Phase transformation-induced plasticity Deformation mechanism