Fuzzy-small degrees of freedom representation of linear and angular variations in mechanical assemblies for tolerance analysis and allocation

Khodaygan, S.; Movahhedy, Mohammad R.; Foumani, Mahmoud Saadat

doi:10.1016/j.mechmachtheory.2010.11.004

Cited by 36 publications

(14 citation statements)

References 15 publications

(24 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence, it should be taken into special consideration during the configuration and allocation of appropriate dimensional errors in the design of machine tools, in order to provide satisfactory machining accuracy and cost-effective geometric accuracy allocation, which is an intractable problem for machine tool manufacturers. Considering that machine tools are usually made by several assembly parts, the dimensional and geometric variations of each part have to be specified by tolerances which guarantee a certain level of quality, in terms of satisfying functional requirements [36]. As a result, accuracy design of machine tools is a problem of allocation of these geometric errors and such problem can be divided into two aspects: one is how to establish a geometric error model to obtain the coupling relationship between the individual errors of the components of the machine tool and its volumetric accuracy, while the other is to perform the geometric error allocation.…”

Section: Introductionmentioning

confidence: 99%

An approach of comprehensive error modeling and accuracy allocation for the improvement of reliability and optimization of cost of a multi-axis NC machine tool

Zhang

Liu

Cheng

et al. 2016

Int J Adv Manuf Technol

View full text Add to dashboard Cite

Machining accuracy is critical for the quality and performance of a mechanical product, and the reliability of a multi-axis NC machine tool reflects the ability to reach and maintain the required machining accuracy. The objective of this study is to propose a general methodology that will simultaneously consider geometric errors and thermal-induced errors to allocate the geometric accuracy of components, for improving machining accuracy reliability under certain design requirements. The multi-body system (MBS) theory was applied to develop a comprehensive volumetric error model, showing the coupling relationship between the individual errors of the components of this machine tool and their volumetric accuracy. Additionally, a thermal error model was established based on the neural fuzzy control theory and was compared to the common thermal error modeling method called BP neural network. Based on the traditional cost model and the reliability analysis model, a geometric error-cost model and a geometric error-reliability model were established, taking the weighted function principle into consideration. Then, an allocation approach of the geometric errors, for optimizing total cost (manufacture and QLF) and reliability, subject to the geometrical and operational constraints of the machine tool, was proposed and formulated into a mathematical model, in order to perform the optimization process of accuracy allocation by using the advanced NSGA-II algorithm. A case study was also performed in a five-axis machine tool, and the traditional NSGA algorithm was used for comparison. The optimization results for the five-axis machining center showed that the proposed approach is effective and able to perform the optimization of geometric accuracy and improve the machining accuracy and the reliability of the machine tool.

show abstract

Section: Introductionmentioning

confidence: 99%

An approach of comprehensive error modeling and accuracy allocation for the improvement of reliability and optimization of cost of a multi-axis NC machine tool

Zhang

Liu

Cheng

et al. 2016

Int J Adv Manuf Technol

View full text Add to dashboard Cite

show abstract

“…As a result, machine tool has to maintain its accuracy for quality control of products [4]. Machine tools are usually made by several assembling parts, and the dimensional and geometric variations of each part have to be specified by tolerances which guarantee a certain level of quality in terms of satisfying functional requirements [5]. Machining accuracy retainability reflects the reliability and robustness of machine tools and its optimization is a problem of the distribution of accuracy of machine tools by allocating tolerances of these geometric errors.…”

Section: Introductionmentioning

confidence: 99%

An approach to optimize the machining accuracy retainability of multi-axis NC machine tool based on robust design

Cai

Zhang

Cheng

et al. 2016

Precision Engineering

View full text Add to dashboard Cite

“…Such specifications guarantee a certain level of quality in terms of satisfying the functional requirements. 5 Therefore, accuracy allocation in a machine tool is a problem related to tolerance synthesis.…”

Section: Introductionmentioning

confidence: 99%

“…5,9 As a result, the functional performance is improved. On the other hand, a 'loose' tolerance reduces the manufacturing cost but may, at the same time, considerably lower the product's quality level.…”

Section: Introductionmentioning

confidence: 99%

Robust geometric accuracy allocation of machine tools to minimize manufacturing costs and quality loss

Cheng

Zhao

Liu

et al. 2016

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

With increasing demands of machining accuracy, designing of machine tools for satisfactory performance using costeffective geometric accuracy configurations is becoming a complex problem to the machine tool manufacturers. In this paper, a novel robust accuracy allocation method is proposed for multi-axis machine tools based on multi-objective quality and cost trade-offs. To model the volumetric accuracy of machine tool based on geometric errors, the multi-body system theory was introduced. A manufacturing cost model for the machine tool components with a significant effect on geometric errors was established based on the machining features. The quality loss of the machine tool was also integrated into a single optimization objective. After identifying the relationship between the accuracy grade parameters of the feeding components and the geometric errors, the maximum in the Euclidean norm of all the accuracy parameters was defined as another optimization objective. The robust accuracy allocation was performed using Isight software and the Non-Dominated Sorting Genetic Algorithm-II built in the MATLAB. The optimization results for a four-axis horizontal machining center showed that the proposed method can realize the optimization of geometric accuracy and can determine the optimal accuracy grade of the feeding components satisfying the machining accuracy requirements.

show abstract

Fuzzy-small degrees of freedom representation of linear and angular variations in mechanical assemblies for tolerance analysis and allocation

Cited by 36 publications

References 15 publications

An approach of comprehensive error modeling and accuracy allocation for the improvement of reliability and optimization of cost of a multi-axis NC machine tool

An approach of comprehensive error modeling and accuracy allocation for the improvement of reliability and optimization of cost of a multi-axis NC machine tool

An approach to optimize the machining accuracy retainability of multi-axis NC machine tool based on robust design

Robust geometric accuracy allocation of machine tools to minimize manufacturing costs and quality loss

Contact Info

Product

Resources

About