检索结果-南通市图书馆

Conditions for Parallel Realizable Configurations in Synthesis of Constraint-based Flexure Mechanisms

Chinese Journal of Mechanical Engineering 2012年第6期25卷 1086-1095页

作者： li shouzhong, yu jingjun**,{2., beihang university, beijing 100191, China 1. robotics institute Beihang University Beijing 100191 China

In synthesis of flexure mechanism, parallel arrangement is paid more attention due to its advantages, such as compact structure and higher stiffness. Researchers have derived many parallel flexure mechanisms, but seldom discuss which kind of flexure mechanism can be realized via fully parallel arrangement. The realizable conditions proposed in current work are complicated to engineering applications. To solve two problems on how to judge whether a flexure mechanism can be realized via fully parallel arrangement and how to realize those flexure mechanisms which cannot be realized via fully parallel arrangement, the algebraic condition is derived to judge whether a freedom space is parallel realizable after introducing the definition of parallel realizable and some propositions, and the condition is there exist 6-n independent line constraints in constraint space reciprocal to dimensional freedom space. Then the realizable constraint spaces reciprocal to freedom spaces with 1-3 dimensions are provided. As a result, not all freedom spaces are parallel realizable. For freedom spaces that are not parallel realizable, the criterion of decomposing DOF is proposed to achieve all motion patterns via parallel or hybrid arrangement, that is a high dimensional freedom space can be realized via combining several low dimensional freedom spaces which are parallel realizable. Specific decomposing strategies for 4 and 5 DOF are provided and a complete flowchart is presented to guide designing flexure mechanisms, particularly those which are not parallel realizable. As case studies, synthesis processes of two helical and 3T1R motions are provided to illustrate the proposed approach. The proposed method provides a feasible approach to realize all motion patterns.

关键词： flexure mechanism type synthesis screw theory line geometry constraint design

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

A unified approach to type synthesis of both rigid and flexure parallel mechanisms

引用

Science China(Technological Sciences) 2011年第5期54卷 1206-1219页

作者： yu jingjun {2. PEI Xu BI ShuSheng {2. guanghua robotics institute Beihang University Beijing 100191 China

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.

关键词： type synthesis flexure mechanism parallel mechanism screw system building block

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numeration and type synthesis of 3-DOF orthogonal translational parallel manipulators

引用

Progress in Natural Science:Materials International 2008年第5期18卷 563-574页

作者： jingjun yua, Jian S. Dai b, Shusheng Bi a, {2. {2. a a robotics institute, beihang university, beijing 100083, China b Department of Mechanical Engineering, School of Physical Science and Engineering, King’s College, university of London, The Strand, London WC2. 2.S, UK robotics institute Beihang University Beijing 100083 China Department of Mechanical Engineering School of Physical Science and Engineering King’s College University of London The Strand London WC2R 2LS UK

Low-degree-of-freedom (Low-DOF) parallel manipulators (PMs) have drawn extensive interests, particularly in type synthesis in which two main formal approaches were established by using the reciprocal screw system theory and lie group theory. This paper aims at numeration and type synthesis of orthogonal translational parallel manipulators (OTPMs) by resorting to an integration of the group- based method and graphical representation of the topology. For this purpose, the concept of Cartesian DOF-characteristic matrix, orig- inated from displacement subgroup and displacement submanifold, is proposed. A new approach based on the combination of the atlas of Cartesian DOF-characteristic matrix and the displacement group-theoretic method is addressed for both exhaustive classi cation and type synthesis of OTPMs. The proposed approach is prone to construct an orthogonal structure and is easy to realize the complete clas- si cation and exhaustive enumeration of this class of low-DOF PMs.

关键词： Type synthesis Displacement group Orthogonal translational parallel manipulator

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Type synthesis of parallel mechanisms with three translational degrees of freedom

引用

Progress in Natural Science:Materials International 2003年第7期 58-67页

作者： yu jingjun , ZHAO Tieshi, BI Shusheng, {2. {2. and HUANG Zhen (1. robotics institute, beijing university of Aeronautics & Astronautics, beijing 100083, China 2. robotics Research Center, Yanshan university, Qinhuangdao 066004, China) robotics institute Beijing University of Aeronautics & Astronautics Beijing 100083 China robotics Research Center Yanshan University Qinhuangdao 066004 China

A simple but effective type synthesis method for spatial parallel mechanisms with three translational degrees of freedom (DOF) based on the screw theory is presented. Firstly all possible connecting-chain structures of three-DOF parallel mechanisms are enumerated. According to the reciprocal relationship between screw constraint forces and the motion screw, a novel synthesis method is presented. By using this method, type synthesis for translational three-DOF parallel mechanisms has been made in a systematic and detailed way. As a result, dozens of novel parallel mechanisms generating spatial translation have been obtained. To verify the significance of type synthesis for this kind of mechanism, this paper also gives an example of application, which is used for a micromanipulator for manipulating cells.

关键词： type synthesis parallel mechanism screw theory micromanipulator degree of freedom.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Geometric Approach for Kinematic Analysis of a Class of 2.DOF Rotational Parallel Manipulators

引用

Chinese Journal of Mechanical Engineering 2012年第2期25卷 241-247页

作者： DONG Xin yu jingjun CHEN Bin {2. {2. robotics institute Beihang UniversityBeijing 100191China

Euler angles are commonly used as the orientation representation of most two degrees of freedom（2.DOF） rotational parallel mechanisms（RPMs）,as a result,the coupling of two angle parameters leads to complexity of kinematic model of this family of *** a simple analytical kinematic model with respect to those parameters representing the geometrical characteristics of the mechanism,is very helpful to improve the performance of *** this paper,a new geometric kinematic modeling approach based on the concept of instantaneous single-rotation-angle is proposed and used for the 2.DOF RPMs with symmetry in a homo-kinetic *** authors＇ knowledge,this is a new contribution to parallel *** means of this method,the forwards kinematics of 2.DOF RPMs is derived in a simple way,and three cases i.e.4-4R mechanism（Omni-wrist III）,spherical five-bar one,and 3-RSR1-SS one demonstrate the validity of the proposed geometric *** addition,a novel 2.DOF RPM architecture with virtual center-of-motion is presented by aid of the same *** result provides a useful tool for simplifying the model and extending the application of the RPMs.

关键词： parallel manipulator kinematics singularity workspace

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：