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| 1 | ;ast forward kinematics algorithm for real-time and ligh-precision control of the 3-RPS parallel mechanism显示文摘 | Yue WANG Jingjun YU Xu PEI | 2018 | Frontiers of Mechanical Engineering2018，13，3： | 9 |
| 2 | A unified approach to type synthesis of both rigid and flexure parallel mechanisms显示文摘Type synthesis of both rigid and compliant parallel mechanisms has become a hot issue in the field of mechanisms and robotics research in recent years. A unified approach to type synthesis of the two classes of mechanisms, however, has not been referred and investigated up to date. Based on the state-of-art analysis for several major type synthesis approaches related to rigid and compliant mechanisms, respectively, it proves feasible to establish a unified methodology for type synthesis of these two classes of mechanisms. That is a synthesis philosophy in terms of the hierarchy mapping between mathematic, physical, and mechanical building blocks in the framework of screw theory, as addressed in this paper. The key point of the proposed method lies in establishing the mapping among three different building blocks (i.e. geometric building block, kinematic or constraint building block, and mechanical building block). As a result, it makes the whole type synthesis process simple and visible. By using the proposed method, two examples are taken to verify the effectiveness for the type synthesis of both rigid and flexure mechanisms. The content of this paper may provide a theoretical frame for constructing a visualized algorithm or software about the unified type synthesis (or conceptual design) of both rigid and flexure parallel mechanisms. | YU JingJun LI ShouZhong PEI Xu BI ShuSheng ZONG GuangHua | 2011 | Science China(Technological Sciences)2011，54，5： | 8 |
| 3 | Intensive phototherapy vs.exchange transfusion for the treatment of neonatal hyperbilirubinemia:a multicenter retrospective cohort study显示文摘Background:Intensive phototherapy(IPT)and exchange transfusion(ET)are the main treatments for extreme hyperbilirubinemia.However,there is no reliable evidence on determining the thresholds for these treatments.This multicenter study compared the effectiveness and complications of IPT and ET in the treatment of extreme hyperbilirubinemia.Methods:This retrospective cohort study was conducted in seven centers from January 2015 to January 2018.Patients with extreme hyperbilirubinemia that met the criteria of ET were included.Patients were divided into three subgroups(low-,medium-,and high-risk)according to gestational week and risk factors.Propensity score matching(PSM)was performed to balance the data before treatment.Study outcomes included the development of bilirubin encephalopathy,duration of hospitalization,expenses,and complications.Mortality,auditory complications,seizures,enamel dysplasia,ocular motility disorders,athetosis,motor,and language development were evaluated during follow-up at age of 3 years.Results:A total of 1164 patients were included in this study.After PSM,296 patients in the IPT only group and 296 patients in the IPT plus ET group were further divided into the low-,medium-,and high-risk subgroups with 188,364,and 40 matched patients,respectively.No significant differences were found between the IPT only and IPT plus ET groups in terms of morbidity,complications,and sequelae.Hospitalization duration and expenses were lower in the low-and medium-risk subgroups in the IPT only group.Conclusions:In this study,our results suggest that IPT is a safe and effective treatment for extreme hyperbilirubinemia.The indication of ET for patients with hyperbilirubinemia could be stricter.However,it is necessary to have a contingency plan for emergency ET as soon as IPT is commenced especially for infants with risk factors.If IPT can be guaranteed and proved to be therapeutic,ET should be avoided as much as possible. | Meng Zhang Yang He Jun Tang Wenbin Dong Yong Zhang Benjin Zhang Hong Wan Quanmin Deng Lirong Guan Bin Xia Zhong Chen Min Ge Jing Zhao Wenxing Li Jingjun Pei Yi Qu Dezhi Mu | 2022 | Chinese Medical Journal2022，，5： | 7 |
| 4 | Hierarchical coupling effect in hollow Ni/NiFe2O4-CNTs microsphere via spray-drying for enhanced oxygen evolution electrocatalysis显示文摘Design and fabrication of cost-effective transition metal and their oxides-based nanocomposites are of paramount significance for metal-air batteries and water-splitting.However,the traditional optimized designs for nanostructure are complicated,low-efficient and underperform for wide-scale applications.Herein,a novel hierarchical framework of hollow Ni/NiFe2O4-CNTs compositemicrosphere forcibly-assembled by zero-dimensional(OD)Ni/NiFo204 nanoparticle(<16 nm)and one-dimensional(1D)self-supporting CNTs was fabricated successfully.Benefitted from the unique nanostructure,such monohybrids can achieve remarkable oxygen evolution reaction(OER)performance in alkaline media with a low overpotential and superior durability,which exceeds most of the commercial catalysts based on IrO/RuO2 or other non-noble metal nanomaterials.The enhanced OER performance of Ni/NiFe2OA-CNTs composite is mainly ascribed to the increased catalytic activity and the optimized conductivity induced by the effects of strong hierarchical coupling and charge transfers between CNTs and Ni/NiFe204 nanoparticles.These effects are greatly boosted by the polarized heterojunction interfaces confirmed by electron holography.The density functional theory(DFT)calculation indicates the epitaxial Ni further enriches the intrinsic electrons contents of NiFe204 and thus accelerates absorption/desorption kinetics of OER intermediates.This work hereby paves a facile route to construct the hollow composite microsphere with excellent OER electrocatalytic activity based on non-noble metal oxide/CNTs. | Xuefeng Yu Guanyu Chen Yizhe Wang Jiwei Liu Ke Pei Yunhao Zhao Wenbin You Lei Wang Jie Zhang Linshen Xing Jingjun Ding Guangzhou Ding Min Wang Renchao Che | 2020 | Nano Research2020，13，2： | 3 |
| 5 | Design of Compliant Straight-line Mechanisms Using Flexural Joints显示文摘Straight-line compliant mechanisms are important building blocks to design a linear-motion stage,which is very useful in precision applications.However,only a few configurations of straight-line compliant mechanisms are applicable.To construct more kinds of them,an approach to design large-displacement straight-line flexural mechanisms with rotational flexural joints is proposed,which is based on a viewpoint that the straight-line motion is regarded as a compromise of rigid and compliant parasitic motion of a rotational flexural joint.An analytical design method based on the Taylor series expansion is proposed to quickly obtain an approximate solution.To illustrate and verify the proposed method,two kinds of flexural joints,cross-axis hinge and leaf-type isosceles-trapezoidal flexural(LITF)pivot are used to reconstruct straight-line flexural mechanisms.Their performances are obtained by analytic and FEA method respectively.The comparisons of the results show the accuracy of the approach.Both examples show that the proposed approach can convert a large-deflection flexural joint into approximate straight-line mechanism with a high linearity that is higher than 5 000within 5 mm displacement.This can lead to a new way to design,analyze or optimize straight-line flexure mechanisms. | PEI Xu YU Jingjun ZONG Guanghua BI Shusheng | 2014 | Chinese Journal of Mechanical Engineering2014，27，1： | 3 |
| 6 | Classifi- cation and type synthesis of 1 DOF remote center of motion mechanisms显示文摘 | Zong Guanghua Pei Xu Yu Jingjun | 2008 | Mechanism and Machine Theory2008，43，12： | 1 |
| 7 | The modeling of leaf-type isosceles-trapezoidal flexural pivots显示文摘 | PEI Xu YU Jingjun ZONG Guanghua | 2008 | Journal of Mechanical Design2008，130，8： | 1 |
| 8 | A novel family of leaf-type compliant joints:Combination of two isosceles-trapezoidal flexural pivots in series显示文摘 | PEI Xu YU Jingjun ZONG Guanghua | 2009 | Journal of Mechanism and Robotics2009，1，02： | 1 |
| 9 | A compound load simulator based on zero-torsion parallel mechanisms显示文摘 | Yu Jingjun Li Wei Pei Xu | | 0，，01： | 1 |
| 10 | A novel obstacle avoidance heuristic algorithm of continuum robot based on FABRIK显示文摘Obstacle avoidance and path planning of continuum robots are challenging tasks due to the hyper-redundant degree of freedoms(DOFs)and restricted working environments.Meanwhile,most current heuristic algorithm-based obstacle avoidance algorithms exist with low computational efficiency,complex solution process,and inability to add global constraints.This paper proposes a novel obstacle avoidance heuristic algorithm based on the forward and backward reaching inverse kinematics(FABRIK)algorithm.The update of key nodes in this algorithm is modeled as the movement of charges in an electric field,avoiding complex nonlinear operations.The 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 advance.This algorithm is characterized by a high convergence rate,low computational cost,and can be used for real-time applications.The proposed approach also has wide applicability and can be applied to both mobile and fixed-base continuum robots.And it can be further extended to the field of hyper-redundant robots.The 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. | WU HaoRan YU JingJun PAN Jie PEI Xu | 2022 | Science China(Technological Sciences)2022，65，12： | 0 |
| 11 | Motion capability analysis of a quadruped robot as a parallel manipulator显示文摘这份报纸在四倍的位置阶段作为一个平行操纵者论述一封四足动物机器人威信的前面、反的排水量分析,它被用来获得工作区并且控制身体的运动。根据四足动物哺乳动物的结构设计的机器人威信对不仅散步有能力并且上交不平的地面,而且在四倍的位置阶段作为一个平行操纵者完成各种各样的操作任务。后者将然而是这份报纸的焦点。为这个目的,腿 kinematics 首先被分析,它在作为一个平行操纵者以运动和身体 kinematics 分析计划的步法上打基础。当机器人的所有四只脚在地面上联系时,由假定,在脚没有滑倒,当一个被动球形的关节和平行操纵者的运动学的模型被建立,每个联系的点被对待。为从所有 12 个可选的关节为平行操纵者选六为非冗余的激活的关节的方法被详细描述。平行操纵者的反、前面的排水量分析用并列转变的方法被执行。基于逆和向前运动学的模型,最后,获得平行操纵者的可达到的工作区并且计划身体的运动上的二个问题被亚当斯模拟实现并且验证。 | Jingjun YU Dengfeng LU Zhongxiang ZHANG Xu PEI | 2014 | Frontiers of Mechanical Engineering2014，9，4： | 0 |
| 12 | A novel medium-entropy(TiVNb)_(2)AlC MAX phase:Fabrication,microstructure,and properties显示文摘Medium-or high-entropy materials have great potential for applications due to their diverse compo-sitions and unexpected physicochemical properties.Herein,a novel medium-entropy(TiVNb)_(2)AlC was synthesized via hot pressing at 1400℃from three individual M_(2)AlC(M=Ti,V,Nb)MAX phases.The microstructure of(TiVNb)_(2)AlC was characterized from the microscale to the atomic scale by scanning electron microscope microscopy(SEM),scanning transmission electron microscopy(STEM),and energy dispersive spectroscopy(EDS).The results showed that Ti,V,and Nb atoms were fully solid-soluble in the M-sites of the M_(2)AlC MAX phase.Compared with three individual MAX phases,the thermal conduc-tivity of(TiVNb)_(2)AlC was reduced greatly in the temperature range of 293-1473 K,and its mechanical properties(including Young’s modulus,Vickers hardness,and bending strength)were all increased due to the solid solution strengthening and electronic mechanism. | Guangqi He Yi Zhang Pei Yao Xingchao Li Ke Ma Jun Zuo Meishuan Li Changsheng Liu Jingjun Xu | 2023 | Journal of Materials Science & Technology2023，，6： | 0 |
| 13 | Design and modeling of continuum robot based on virtual-center of motion mechanism显示文摘Continuum robot has attracted extensive attention since its emergence.It has multi-degree of freedom and high compliance,which give it significant advantages when traveling and operating in narrow spaces.The flexural virtual-center of motion(VCM)mechanism can be machined integrally,and this way eliminates the assembly between joints.Thus,it is well suited for use as a continuum robot joint.Therefore,a design method for continuum robots based on the VCM mechanism is proposed in this study.First,a novel VCM mechanism is formed using a double leaf-type isosceles-trapezoidal flexural pivot(D-LITFP),which is composed of a series of superimposed LITFPs,to enlarge its stroke.Then,the pseudo-rigid body(PRB)model of the leaf is extended to the VCM mechanism,and the stiffness and stroke of the D-LITFP are modeled.Second,the VCM mechanism is combined to form a flexural joint suitable for the continuum robot.Finally,experiments and simulations are used to validate the accuracy and validity of the PRB model by analyzing the performance(stiffness and stroke)of the VCM mechanism.Furthermore,the motion performance of the designed continuum robot is evaluated.Results show that the maximum stroke of the VCM mechanism is approximately 14.2°,the axial compressive strength is approximately 1915 N/mm,and the repeatable positioning accuracies of the continuum robot is approximately±1.47°(bending angle)and±2.46°(bending direction). | Guoxin LI Jingjun YU Yichao TANG Jie PAN Shengge CAO Xu PEI | 2023 | Frontiers of Mechanical Engineering2023，18，2： | 0 |
| 14 | Cusp points and assembly changing motions in the PRR-PR-PRR planar parallel manipulator显示文摘Most parallel manipulators have multiple solutions to the direct kinematic problem.The ability to perform assembly changing motions has received the attention of a few researchers.Cusp points play an important role in the kinematic behavior.This study investigates the cusp points and assembly changing motions in a two degrees of freedom planar parallel manipulator.The direct kinematic problem of the manipulator yields a quartic polynomial equation.Each root in the equation determines the assembly configuration,and four solutions are obtained for a given set of actuated joint coordinates.By regarding the discriminant of the repeated roots of the quartic equation as an implicit function of two actuated joint coordinates,the direct kinematic singularity loci in the joint space are determined by the implicit function.Cusp points are then obtained by the intersection of a quadratic curve and a cubic curve.Two assembly changing motions by encircling different cusp points are highlighted,for each pair of solutions with the same sign of the determinants of the direct Jacobian matrices. | Chengwei SHEN Jingjun YU Xu PEI | 2023 | Frontiers of Mechanical Engineering2023，18，2： | 0 |
| 15 | A novel shape memory alloy actuated soft gripper imitated hand behavior显示文摘The limited length shrinkage of shape memory alloy(SMA)wire seriously limits the motion range of SMA-based gripper.In 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 environment.Through imitating palm movement,a structure with adjustable spacing between fingers was made using SMA spring and rigid spring.The hook structure design at the fingertip can form self-locking to further improve the load capacity of gripper.Through the long thin rod model,the relationship of the initial pre bent angle on the bending angle and output force of the finger was analyzed.The stress-strain model of SMA spring was established for the selection of rigid spring.Three grasping modes were proposed to adapt to the weight of the objects.Through the test of the gripper,it was proved that the gripper had large bending amplitude,bending force,and response rate.The design provides a new idea for the lightweight design and convenient design of soft gripper based on SMA. | Jie PAN Jingjun YU Xu PEI | 2022 | Frontiers of Mechanical Engineering2022，17，4： | 0 |
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