The spherical 5R parallel manipulator is a typical parallel manipulator. It can be used as a pointing device or as a minimally invasive surgical robot. This study addresses the motion/force transmission analysis and optimization of the manipulator by taking into account the motion/force transmissibility. The kinematics of the manipulator is analyzed. Several transmission indices are defined by using screw theory for the performance evaluation and dimensional synthesis. The process of determining the optimal angular parameters based on performance charts is presented. The manipulator that has a large workspace and good motion/force transmissibility is identified.

Optimal Design of Spherical 5R Parallel Manipulators Considering the Motion/Force Transmissibility

In this paper the effect of kinematic redundancy in order to reduce the singularity loci of the direct kinematics and to increase the operational, i.e., singularityfree, workspace is demonstrated. The proposed approach consists of additional prismatic actuators allowing one or more base joints to move linearly. As a result, a selective reconfiguration can be performed in order to avoid singular configurations. Exemplarily, kinematically redundant schemes of four structures, the 3RRR, the 3RPR, the 6UPS, and the 6RUS, are considered. The relationship between the redundancy and the operational workspace is studied and several analysis examples demonstrate the effectiveness of the proposed concept. Furthermore, the additional benefit of an increasing number of redundant actuators is discussed.

Influence of kinematic redundancy on the singularity-free workspace of parallel kinematic machines

This paper presents a novel idea for determining the reachable and dexterous workspace of parallel manipulators. Both the reachable workspace and dexterous workspace are utmost important for optimal design and performance comparison of manipulators, because each configuration or point in this region has specified kinematic dexterity by the designer. We propose a uniform algorithm, called stratified workspace boundary determining algorithm (SWBDA), which considers various physical and contrived constraints. The problems of determining the reachable and dexterous workspace boundaries are defined and the unified method is applied to solve all the problems of this kind. The validity and efficiency of the proposed method are verified with two kinds of representative parallel manipulator, since their relational results were studied in literatures. Finally, the advantages of the proposed method are summarized by comparing with other methods.

A unified algorithm to determine the reachable and dexterous workspace of parallel manipulators

This paper deals with the forward displacement analysis and singularity analysis of a 2-DOF 5R spherical parallel manipulator. An alternative formulation of the kinematic equations of the 2-DOF spherical parallel manipulator is proposed. A formula is then derived to produce directly the unique current solution to the FDA of the 2-DOF spherical parallel manipulator. It is proved that the formula is associated with the same assembly mode and working mode as the reference configuration of the spherical parallel manipulator. Unlike other parallel manipulators, the 2-DOF 5R spherical parallel manipulator always undergoes self-motion in a Type 2 singular configuration, and the 3R leg of the 2-DOF spherical parallel manipulator also always undergoes self-motion in a Type 1 singular configuration.Copyright © 2009 by ASME

Forward Displacement Analysis and Singularity Analysis of a 2-DOF 5R Spherical Parallel Manipulator

Design of Large Motion Range and Heavy Duty 2-DOF Spherical Parallel Wrist Mechanism

Firstly, reachable workspace of 2-DOF spherical 2R serial manipulator has been studied and classified. On this basis, the theoretical workspace of 2-DOF spherical 5R parallel manipulator has been also studied and its design space was established. The shapes of theoretical workspace have been classified in the design space and expressed on the plane by using conformal transformation. These results would be very useful for designers to understand and grasp the performances of the manipulator's workspace

Analysis of the workspace of 2-DOF spherical 5R parallel manipulator

The mechanical design of manipulator is based on performance index, which will be determined for construction parameters. in order to discuss the relationship between performance index and dimensional parameter of Planar 2-DOF Parallel Manipulator with Actuation Redundancy, in this paper, firstly the design space and kinematics equation are established, the inverse kinematics is obtained, the reachable workspace is analyzed by geometrical method in detail, the relationship between reachable workspace and link length is obtained, and plotting the area performance atlas corresponding to reachable workspace in the design space, finally discussing the mathematical condition on which the singular configuration of the manipulator occurs and analytical method of singular track or singular loci is obtained.

Analysis of the Workspace and Singularity of Planar 2-DOF Parallel Manipulator with Actuation Redundancy

The research subject of this paper is spherical 5R parallel manipulator, on the basis of analysis of kinematics of the manipulator, the dynamic model of the manipulator was established by virtue of Lagrange method, and via numerical calculating example, the dynamic model of the manipulator was simulated by two software Matlab and ADAMS, by comparing the results obtained by two software, we proved that the dynamic model of the spherical 5R parallel manipulator is right, which provide theoretical foundation for manufacturing sample.

Dynamic analysis of spherical 5R parallel manipulator

The research subject of this paper is spherical 2-DOF parallel manipulator with actuation redundancy, based on kinematic analysis of the manipulator, the inverse dynamic model of the manipulator was established by virtue of Lagrange method. Because end-effector of the manipulator possess 2-DOF, but corresponding 3 driving input, so driving moment of the manipulator has infinite group value in theory, resulting in that assignment of driving moment is non-unique, in this paper, driving moment was optimized by force optimization method and energy consumption optimization method. And via numerical calculating example, comparing the driving moment curve obtained by two methods, we proved that performance of the manipulator was improved because of importing redundant drive, which provide theoretical foundation for establishing control model.

Dynamic analysis of spherical 2-DOF parallel manipulator with actuation redundancy

As a new type of hydraulic system, the independent valve control system (IMCS) has higher flexibility compared with the traditional four-side slide valve control system. The independent metering control system (IMCS) is divided into four quadrant modes, based on the speed and load of the actuator. The traditional control methods always use a discrete control strategy to realize the switching between different modes based on mode recognition. However, the spool signals frequently switch, and the actuator operating pressure and speed are not stable when the IMCS is switched between different modes. To solve the above problems, this paper proposes a continuous control strategy for the IMCS. Based on the fuzzy control principle, the variable universe fuzzy controller (VUFC) was designed. The controller contains 49 fuzzy rules, and the output of the controller at any time is calculated by the weighted sum of several fuzzy rules. The VUFC divides the system into 49 rules, which are activated by multiple modes at any time to achieve a smooth transition between different modes. The VUFC was verified in a 37 ton excavator model and compared with the traditional independent metering meter-out (IM_MO) control strategy. The results showed that the VUFC significantly improved the frequent switching of the spool signals, and the running speed and pressure stability of the hydraulic cylinder were significantly improved. At the same time, the response speed of the hydraulic cylinder became faster at the start of the system. The VUFC can realize the continuous control of the IMCS and improve the operating performance of excavators.

/pdf/variable-universe-fuzzy-controller-for-an-independent-1t5jpgmg.pdf

Variable Universe Fuzzy Controller for an Independent Metering System of Construction Machinery

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Yong-Quan Li

Author Tools

Chat about Author