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Comparative Analysis of Characteristics of the Coupled and Decoupled Parallel Mechanisms

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 468-476页

作者： ZENG Daxing hou yulei LU Wenjuan HUANG Zhen College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China

The existence of coupling makes the parallel mechanism possess some special advantages over the serial mechanism, while it is just the coupling that brings about the parallel mechanism some limitations, such as complex workspace, high nonlinear relationship between input and output, difficulties in static and dynamic analysis, and the development of control system, which restricts its application fields. The decoupled parallel mechanism is currently one of the research focuses of the mechanism fields, while the study on the different characteristics between the deeoupled and coupled parallel mechanisms has not been reported. Therefore, this paper performs the systematic comparative analysis of the 3-RPUR and the 3-CPR parallel mechanisms. The features of the two mechanisms are described and their movement forms are analyzed with screw theory. The inverse and forward displacement solutions are solved and the Jacobian matrices are obtained. According to the Jacobian matrices and by using the theory of physical model of the solution space, the workspace, dexterity, velocity, payload capability, and stiffness of the mechanisms are analyzed with plotting the indices atlases. The research results prove that the effects of the coupling on the parallel mechanism are double-side, and then the adoption of the decoupled parallel mechanism should be determined by the requirements of the concrete application situation. The contents of this paper should be useful for the type synthesis and practical application of the parallel mechanism.

关键词： parallel mechanism couple decouple screw theory index atlas

Biomimetic Shoulder Complex Based on 3-PSS/S Spherical Parallel Mechanism

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 29-37页

作者： hou yulei HU Xinzhe ZENG Daxing Zhou Yulin School of Mechanical Engineering Yanshan University

The application of the parallel mechanism is still limited in the humanoid robot fields, and the existing parallel humanoid robot joint has not yet been reflected the characteristics of the parallel mechanism completely, also failed to solve the problem, such as small workspace, effectively. From the structural and functional bionic point of view, a three degrees of freedom（DOFs） spherical parallel mechanism for the shoulder complex of the humanoid robot is presented. According to the structure and kinetic characteristics analysis of the human shoulder complex, 3-PSS/S（P for prismatic pair, S for spherical pair） is chosen as the original configuration for the shouder complex. Using genetic algorithm, the optimization of the 3-PSS/S spherical parallel mechanism is performed, and the orientation workspace of the prototype mechanism is enlarged obviously. Combining the practical structure characteristics of the human shouder complex, an offset output mode, which means the output rod of the mechanism turn to any direction at the point a certain distance from the rotation center of the mechanism, is put forward, which provide possibility for the consistent of the workspace of the mechanism and the actual motion space of the human body shoulder joint. The relationship of the attitude angles between different coordinate system is derived, which establishs the foundation for the motion descriptions under different conditions and control development. The 3-PSS/S spherical parallel mechanism is proposed for the shoulder complex, and the consistence of the workspace of the mechanism and the human shoulder complex is realized by the stuctural parameter optimization and the offset output design.

关键词： shoulder complex biomimetics spherical parallel mechanism

Development and Calibration of a Hyperstatic Six-component Force/Torque Sensor

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 505-513页

作者： hou yulei YAO Jiantao ZENG Daxing CHEN Jie ZHAO Yongsheng College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China

The six-component force/torque sensor has become one kind of the most important sensors with the ability of measuring all the external forces and torques. A novel hyperstatic six-component force/torque sensor based on the Stewart platform structure, which can be used for the force measurement of the robot wrist, is proposed, and its structural optimal design, finite element analysis and calibration experimentation is presented. The characteristic of the sensor structure is analyzed in comparison with the traditional Stewart platform-based sensor. The mathematical expression of the sensor＇s force mapping matrix is introduced. The condition number and generalized amplifying coefficient defined by singular values of force Jacobian matrix are used to evaluate the performances of isotropy and sensitivity of the sensor respectively. The optimal design of the sensor structure is performed with the objective of achieving high measurement sensitivity and good isotropy. The sensor prototype is fabricated, and the static and dynamic characteristics of the sensor are analyzed with finite element analysis software package ANSYS. The calibration device is manufactured, and the data acquisition and processing system is developed. The theoretical and experimental study of the static calibration of the sensor prototype is carried out. The results of simulation analysis and calibration experimentation prove the feasibility of the hyperstatic sensor structure, and the contents of this paper possess theoretical significance and engineering value for the further research and practical application of the six-component force sensor.

关键词： force/torque sensor six-component hyperstatic finite element analysis calibration

Mechanics Unloading Analysis and Experimentation of a New Type of Parallel Biomimetic Shoulder Complex

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 649-658页

作者： hou yulei LI Zhisen WANG Yi ZHANG Wenwen ZENG Daxing Zhou Yulin School of Mechanical Engineering Yanshan University

The structure design for high ratio of carrying capacity to deadweight is one of the challenges for the bionic mechanism,while the problem concerning high carrying capacity has not yet be solved for the existing shoulder complex.A new type biomimetic shoulder complex,which adopts 3-PSS/S（P for prismatic pair,S for spherical pair） spherical parallel mechanism（SPM）,is *** static equilibrium equations of each component are established by using the vector method and the equations for constrain forces with certain load are *** the constrain force on the middle limb and that on the side limbs are compared in order to verify the unloading performance of the *** addition,the prototype mechanism of the shoulder complex is developed,and the force feedback experiment is conducted to verify the static analysis,which indicates that the middle limb suffers most of the external force and the effect of mechanics unloading is *** 3-PSS/S spherical parallel mechanism is presented for the shoulder complex,and the realization of mechanics unloading is benefit for the improvement of the carrying capacity of the shoulder complex.

关键词： biomimetic shoulder complex humanoid robot spherical parallel mechanism carrying capacity mechanics unloading

Topological Configuration and Rotation Analysis of the Three⁃Order Rubik􀆳s Cube

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Journal of Harbin Institute of Technology(New Series) 2020年第5期27卷 49-58页

作者： yulei hou Ting Zhou Guoxing Zhang Ming Li Daxing Zeng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina Heavy-duty Intelligent Manufacturing Equipment Innovation Center of Hebei Province Yanshan UniversityQinhuangdao 066004HebeiChina

The mechanism of three⁃order Rubik􀆳s Cube(RC)has the characteristics of recombination and variable degree of freedom,and it is difficult to accurately describe the degree of its *** paper takes RC as the research object,and the adjacency matrix is constructed based on topology and graph theory in order to describe the variation rule of topological configuration in the single layer rotation of *** this paper,the degree of freedom of the RC in any shape can be described by defining the concept of entanglement degree of freedom,establishing a set of adjacency matrix,and determining the degree of freedom of the RC which is attributed to the number of non⁃zero elements in the set of adjacent *** prime number is proposed to describe the rotation of the RC combined with the rotation recognition of RC,which is simple and convenient for computer *** research contents in this paper are beneficial to the study of RC from the perspective of mechanism ***,it is of great significance to the study of other complex mechanisms with variable degrees of freedom.

关键词： mechanism of Rubik􀆳s Cube topological configuration adjacency matrix degree of freedom prime number

Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： Hang Yang yulei Xia Yue Ma Mingtong Gao Shuai hou Shanshan Xu Yanqiang Wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

基于旋量的风载作用3-RSR并联天线机构动力学建模

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振动与冲击 2020年第19期39卷 174-181页

作者：侯雨雷张国兴侯荣伟曾达幸燕山大学机械工程学院河北秦皇岛066004

天线座架动力学问题关系到天线跟踪精度,同时外界风载对天线的影响不应忽视。以3-RSR(R为转动副,S为球面副)并联机构作为天线座架,分析少自由度并联天线机构动力学问题。首先描述并联机构起始位姿状态,通过指数积公式得到并联机构各杆... 详细信息

天线座架动力学问题关系到天线跟踪精度,同时外界风载对天线的影响不应忽视。以3-RSR(R为转动副,S为球面副)并联机构作为天线座架,分析少自由度并联天线机构动力学问题。首先描述并联机构起始位姿状态,通过指数积公式得到并联机构各杆件的位姿矩阵;然后通过运动副关节之间的约束关系,给出并联机构的约束矩阵,得到其雅克比矩阵和各杆件的速度旋量,通过推导约束矩阵的微分形式,获得并联机构各杆件的加速度旋量;其次根据各杆件力的平衡关系,推导并联天线机构的逆动力学模型。考虑风载荷作用提出并联天线机构动力学计算流程,分别运用MATLAB和ADAMS软件在俯仰和方位运动状态下对并联天线机构动力学模型进行仿真,对动力学模型进行求解与验证。研究工作对并联天线机构动力学性能提升及控制实现具有一定指导意义。

关键词：并联机构天线动力学风载荷旋量

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新型两转动自由度完全解耦并联机构及其特性

哈尔滨工业大学学报 2014年第9期46卷 80-85页

作者：侯雨雷张占叶胡鑫喆曾达幸燕山大学机械工程学院河北秦皇岛066004

针对并联机构内部耦合性给其运动学和动力学分析以及控制系统的开发带来的问题,提出一种新型的两自由度转动解耦并联机构.运用约束螺旋法对机构的自由度和运动特性进行分析,通过修正的Kutzbach-Grübler公式计算出机构自由度数目;利用... 详细信息

针对并联机构内部耦合性给其运动学和动力学分析以及控制系统的开发带来的问题,提出一种新型的两自由度转动解耦并联机构.运用约束螺旋法对机构的自由度和运动特性进行分析,通过修正的Kutzbach-Grübler公式计算出机构自由度数目;利用各构件间几何关系,求解机构位置正反解解析表达式;根据机构输入与输出参数间关系式,推导得到机构雅可比矩阵,进而依据雅可比矩阵表达式,验证了机构的解耦特性,并进而讨论了驱动输入的选择对机构奇异的影响.提出的解耦并联机构丰富了机构构型库,对进一步应用具有理论指导意义.

关键词：并联机构转动解耦约束螺旋奇异雅可比矩阵

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一种新型并联式解耦踝关节康复机构及其优化

机械工程学报 2015年第9期51卷 1-9页

作者：曾达幸胡志涛侯雨雷苏永林燕山大学机械工程学院秦皇岛066004

对踝关节功能损伤的患者,尤其是中风患者来讲,踝关节的康复是一项非常困难的问题。针对此提出一种新型并联式解耦踝关节康复机构,并基于中医康复疗法引入踝关节康复机构需要注重牵引功能的设计思路。所提出的机构能够同时实现单独转动康... 详细信息

对踝关节功能损伤的患者,尤其是中风患者来讲,踝关节的康复是一项非常困难的问题。针对此提出一种新型并联式解耦踝关节康复机构,并基于中医康复疗法引入踝关节康复机构需要注重牵引功能的设计思路。所提出的机构能够同时实现单独转动康复(背屈、跖屈,外展、内收)和在牵引下转动的康复过程;利用螺旋理论分析机构在任意位姿下的自由度性质;推导出机构位置正反解,求解速度雅可比矩阵,并对机构进行奇异性分析;通过输出参数对解耦机构杆件尺寸进行优化,基于遗传算法给出数值算例,验证了机构工作空间满足踝关节康复运动的要求。

关键词：踝关节康复并联机构解耦尺寸优化