Design Optimization of Planar Linkage Mechanism with Joint Clearance for Improving the Robustness of Kinematic Accuracy

Based on the fuzzy theory and an idea of multidisciplinary design optimization, a fuzzy optimization model of multidisciplinary design is established. Fuzzy constraints are changed by a fuzzy comprehensive evaluation and an amplification-coefficient method. Using collaborative optimization and genetic algorithms, the multidisciplinary fuzzy optimum of planar linkage mechanism is achieved and a four-bar mechanism is given as an example. Two disciplines are involved in the design optimization of mechanism, i.e., kinematics and control. The numerical results indicate that the optimized mechanism not only satisfies the mechanism and control constraints, but also synthesizes approximate optimum value, and lays a foundation for the solution of more complex mechanical system.

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A Kinematics Velocity Reliability Analyzing Method for Complex Planar Linkage Mechanism Based on Equal-Effective Mechanics Model

Volume 14: Emerging Technologies; Materials: Genetics to Structures; Safety Engineering and Risk Analysis ◽

10.1115/imece2016-65463 ◽

2016 ◽

Author(s):

Jingyi Liu ◽

Yugang Zhang ◽

Wei Guo ◽

Cong Sun

Keyword(s):

Effective Length ◽

Joint Clearance ◽

Linkage Mechanism ◽

Kinematic Parameters ◽

Component Size ◽

Aircraft Cabin ◽

Mechanics Model ◽

Surface Method ◽

Planar Linkage Mechanism ◽

The Relationship

The planar linkage mechanism (PLM) is a kind of familiar mechanism. The accuracy of its kinematic parameters, such as displacement or velocity, is crucial to accomplish its function. The parameters are not always precise due to the indeterminacy of some influencing factors. This paper proposes a methodology to analyze the velocity reliability of PLM based on the equal-effective mechanics model (EMM), with the effect of joint clearance, component size randomness and applied force randomness considered. More specifically, how these factors would influence the EMM is studied and then the motion law and risk velocity point of certain part can be obtained. To model the joint clearance exactly, the concept of effective length is recommend. The Response Surface Method (RSM) is used to express the relationship between input parameters and output parameter (velocity), based on which the reliability analysis is conducted. The sensitivities of the parameters are expressed by Sobol variance analyzing method. Finally a certain aircraft cabin door retractable mechanism (one sort of complex planar linkage mechanism) is selected as an example, showing that the approach proposed this article has a great value to be used for engineering object.

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Design Optimization of RML Glove for Improved Grasp Performance

Volume 1: Advances in Control Design Methods; Advances in Nonlinear Control; Advances in Robotics; Assistive and Rehabilitation Robotics; Automotive Dynamics and Emerging Powertrain Technologies; Automotive Systems; Bio Engineering Applications; Bio-Mechatronics and Physical Human Robot Interaction; Biomedical and Neural Systems; Biomedical and Neural Systems Modeling, Diagnostics, and Healthcare ◽

10.1115/dscc2018-9004 ◽

2018 ◽

Author(s):

Teja Vanteddu ◽

Bijo Sebastian ◽

Pinhas Ben-Tzvi

Keyword(s):

Design Optimization ◽

Daily Living ◽

Experimental Validation ◽

Large Diameter ◽

Future Research ◽

Linkage Mechanism ◽

Design Variables ◽

Wide Range ◽

Optimal Values ◽

Optimal Set

This paper describes the design optimization of the RML Glove in order to improve its grasp performance. The existing design is limited to grasping objects of large diameter (> 110mm) due to its inability in attaining high bending angles. For an exoskeleton glove to be effective in its use as an assistive and rehabilitation device for Activities of Daily Living (ADL), it should be able to interact with objects over a wide range of sizes. Motivated by these limitations, the kinematics of the existing linkage mechanism was analyzed in detail and the design variables were identified. Two different cost functions were formulated and compared in their ability to yield optimal values for the design variables. The optimal set of design variables was chosen based on the grasp angles achieved and the resulting mechanism was simulated in CAD for feasibility testing. An exoskeleton mechanism corresponding to the index finger was manufactured with the chosen design variables and detailed experimental validation was performed to illustrate the improvement in grasp performance over the existing design. The paper ends with a summary of the experimental results and directions for future research.

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Dynamic responses of the planar linkage mechanism with impact in three clearance joints

Advances in Energy Science and Equipment Engineering II ◽

10.1201/9781315116174-46 ◽

2017 ◽

pp. 1079-1083

Author(s):

Zheng Bai ◽

Xin Shi ◽

Ji Zhao

Keyword(s):

Dynamic Responses ◽

Linkage Mechanism ◽

Clearance Joints ◽

Planar Linkage Mechanism

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The Research on Motion Reliability Simulation of Planar Linkage Mechanism

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.591-593.664 ◽

2012 ◽

Vol 591-593 ◽

pp. 664-669

Author(s):

Chao Yan Wan ◽

Wen Cheng Li ◽

Xu Zhao

Keyword(s):

Monte Carlo ◽

Simulation Model ◽

Linkage Mechanism ◽

Random Simulation ◽

Cycle Simulation ◽

Manufacturing Errors ◽

Parameterized Model ◽

Planar Linkage Mechanism ◽

Joint Clearances ◽

Analysis Platform

Taking planar pivot four-bar mechanism for example, the method motion reliability simulation on solving motion reliability of planar linkage mechanism is proposed in this paper. Under the circumstances that manufacturing errors and joint clearances are normal distribution, ADAMS is taken as the analysis platform and the parameterized model of planar linkage mechanism is established by it, then Monte Carlo theory is used to calculate in order that different random simulation model can be obtained. After cycle simulation, the data of simulation will be saved in text files so that it could be used for calculating the result of motion reliability. This method is applied to solving motion reliability of the opening/closing mechanism of the bottom door in the coal hopper, and the result is reasonable, thereby its effectiveness is proved successfully.

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Research on Optimization Design of Folding Tables and Chairs Group Based on ADAMS

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.706-708.1541 ◽

2013 ◽

Vol 706-708 ◽

pp. 1541-1544 ◽

Cited By ~ 1

Author(s):

Si Ming Luo ◽

Lin Wu ◽

Fu Gui Zhu

Keyword(s):

3D Modeling ◽

Optimization Design ◽

3D Model ◽

Linkage Mechanism ◽

Movement Characteristics ◽

Characteristics Analysis ◽

Modeling Software ◽

New Type ◽

Planar Linkage Mechanism

To design a new type of folding tables and chairs group based on the planar linkage mechanism by using a 3D modeling software solidworks and a dynamics analyzing software ADAMS, it is built on four bar mechanism .First ,establish a 3D model of folding tables and chairs group ;Second, simplify the parts of folding; Last but not the least, use the ADAMS to accomplish the optimization design of the group according to the movement characteristics analysis of the corresponding folding parts in the process of expansion and pack up.

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Dynamics Automatic Design of Planar Linkage Mechanism Based on Genetic Program

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.2447 ◽

2011 ◽

Vol 396-398 ◽

pp. 2447-2451

Author(s):

Xian Hai Luo ◽

Liang Zhen Li

Keyword(s):

Fitness Function ◽

Evolutionary Process ◽

Genetic Program ◽

Initial Population ◽

Automatic Design ◽

Kinematic Pair ◽

Linkage Mechanism ◽

Mutation Operators ◽

Planar Linkage Mechanism ◽

Dimension Space

Regarded planar linkage mechanism kinematic target and execution of kinematic pair constraint reaction restrictions as the quantitative objectives, established the comprehensive dynamic design fitness function with the distance between a kinematics target and execution of a set of practical movement points, and the difference between actual constraint reaction of kinematic pair and its limit. According to multi-branch tree expression and random configuration method to create mechanical initial population, driven by the fitness function, made the mechanical population evolution towards the target requirements by the use of copy, crossover and mutation operators of genetic program. In the evolutionary process, inserted kinematics and dynamics automatic analysis technique, design examples indicated that using a genetic program can search parallel in different mechanical configuration space, dimension space and inertia space, automatically searched to such kinds of mechanisms approximate kinematics target and dynamics requirements, thus fulfilling the dynamics automatic design.

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