Robustness Evaluation of a Miniaturized Machine Tool

1999 ◽  
Author(s):  
Nozomu Mishima ◽  
Kousuke Ishii
Keyword(s):  
Machine Tool ◽  
Robust Design ◽  
Design Guidelines ◽  
Design Parameters ◽  
Drive Unit ◽  
Control Factors ◽  
Feed Drive ◽  
Space Saving ◽  
Straightness Error ◽  
Noise Factors

Abstract This paper applies the method of robust design to machine tool design. The new design focuses on miniaturization that provides significant for energy and space saving. Our approach combines an analytical procedure representing the machining motions of a machine tool (form-shaping theory) with procedures for robust design. The effort identifies the design parameters of a machine tool that significantly influence the machining tolerance and leads to a general design guidelines for robust miniaturization. Further, this research applies the Taguchi method to the form-shaping function of a prototype miniature lathe. The analysis addresses five machine tool dimensions as control factors, while treating local errors in the machine structure as noise factors. The robustness study seeks to identify the importance of each factor in improving performance of the machine tool. The result shows that the thickness of the feed drive unit affects the performance most significantly. Among the local errors, straightness error of the same feed drive unit has a critical importance.

Taguchi Robust Design of Exhaust System Based on the Parametrically Process of Parts Location

2013 ◽  
Vol 579-580 ◽  
pp. 894-900
Author(s):  
Teng Fei Li ◽  
Hui Xia Liu ◽  
Yi Xue Mao
Keyword(s):  
Robust Design ◽  
Optimization Design ◽  
Exhaust System ◽  
The Finite Element Method ◽  
Control Factors ◽  
Body Design ◽  
Modal Property ◽  
Noise Factors ◽  
Taguchi Robust Design ◽  
Exhaust Systems

Due to the change of car-body design, the location of exhaust systems hanger is uncertain and always fluctuates around the initial design position. So the Taguchi method is introduced to conduct exhaust systems optimal design. Firstly, the parameterization of hanger location under the grid environment was realized by combining NastranHypermesh and Isight. Then, the Taguchi robust design of the exhaust system is performed taking the hanger location as noise factors and the stiffness of hanger shock absorber as control factors. As a result, modal property and robustness of the exhaust system are improved. At last, the results of Taguchi robust design and traditional sensitivity optimization design based on the finite element method are compared, which reveals the advantage of Taguchi robust design in improving product quality.

A Procedure for Robust Design: Minimizing Variations Caused by Noise Factors and Control Factors

1996 ◽  
Vol 118 (4) ◽  
pp. 478-485 ◽  
Author(s):  
Wei Chen ◽  
J. K. Allen ◽  
Kwok-Leung Tsui ◽  
F. Mistree
Keyword(s):  
Robust Design ◽  
Irrigation System ◽  
Small Variation ◽  
Type I ◽  
Closed Form Solutions ◽  
Control Factors ◽  
Design Variables ◽  
Solar Powered ◽  
And Control ◽  
Noise Factors

In this paper, we introduce a small variation to current approaches broadly called Taguchi Robust Design Methods. In these methods, there are two broad categories of problems associated with simultaneously minimizing performance variations and bringing the mean on target, namely, Type I—minimizing variations in performance caused by variations in noise factors (uncontrollable parameters). Type II—minimizing variations in performance caused by variations in control factors (design variables). In this paper, we introduce a variation to the existing approaches to solve both types of problems. This variation embodies the integration of the Response Surface Methodology (RSM) with the compromise Decision Support Problem (DSP). Our approach is especially useful for design problems where there are no closed-form solutions and system performance is computationally expensive to evaluate. The design of a solar powered irrigation system is used as an example.

A Robust Design Methodology for High-Pressure Compressor Throughflow Optimization

2003 ◽  
Author(s):  
N. Lecerf ◽  
D. Jeannel ◽  
A. Laude
Keyword(s):  
High Pressure ◽  
Standard Deviation ◽  
Robust Design ◽  
Design Methodology ◽  
Engine Performance ◽  
Design Parameters ◽  
Deterministic Optimization ◽  
High Pressure Compressor ◽  
Noise Factors ◽  
Pressure Compressor

Reducing costs and development times are two of the main challenges for aircraft engines manufacturers. Analysis shows that the main troubles encountered during the industrialization phase are due to choices made during the first steps, such as the preliminary design of the compressor throughflow (flowpath and velocity triangles). Therefore, constraints and needs from the later phases have to be taken into account as early as possible. A deterministic optimization method for automated compressor throughflow design has been developed to achieve these objectives, improving efficiency and surge margin while modifying the design parameters. Nevertheless, variability between the theoretical geometry and the actual one may occur because of the manufacturing process or the damages encountered during the engine life cycle. Depending on their magnitude, these differences can affect the engine performance. To consider these random phenomena from the design step, the deterministic optimization is coupled with a probabilistic approach, based on a robust design methodology which aims at guarantee the engine performance despite geometrical variability. This article deals with geometrical robustness. It presents a robust design methodology and introduces a capability function used to optimize the outputs of a compressor model while minimizing their standard deviation. The model has two kinds of inputs: the design factors, which are known by both designer and manufacturer, and the noise factors, that are just known by their mean value and their standard deviation. As robust design requires a large number of calculations, it is interesting to work with an approximated physical model such as a response surface, generated through the computation of a suitable design of experiments. This method has been successfully applied to the design of a Snecma Moteurs high-pressure compressor.

Optimum Size Consideration of Machine Tools

2007 ◽  
Vol 339 ◽  
pp. 337-342 ◽  
Author(s):  
N. Mishima
Keyword(s):  
Machine Tool ◽  
Machine Tools ◽  
Design Method ◽  
Design Guidelines ◽  
Design Tool ◽  
Design Parameters ◽  
Error Sources ◽  
Machine Performance ◽  
Small Machine ◽  
Tool Performance

As has been demonstrated in the “microfactory” which is a miniature manufacturing system proposed by the author’s research group, small machine tools that are comparable in size to their target products lead to large reductions in energy consumption and area. Experiments showed that they were capable of micro mechanical fabrication. However, the design of miniature machine tools has not been fully optimized. The author proposed a design method to estimate machine tool performance. In this paper, the design tool is applied to find miniaturizing strategies. By applying the design tool, it is possible to determine which of the design parameters and error sources would significantly affect machine performance. From the results of calculation, the tool can clarify the effect of machine tool sizes imposed on the machine performances. This leads to some suggestions regarding machine tool sizes. Finally, design guidelines for miniature machine can be obtained.

Robustness Assessment of a Prediffuser, Strut, and Frame

2009 ◽  
Author(s):  
Loren Garrison ◽  
Sarah Walter
Keyword(s):  
Robust Design ◽  
Quality Function Deployment ◽  
Performance Metrics ◽  
Process Analysis ◽  
Aerodynamic Performance ◽  
Operating Conditions ◽  
Design Parameters ◽  
Latin Hypercube Design ◽  
Noise Factors ◽  
Robustness Assessment

For most industrial applications, design and analysis is typically performed using only a nominal geometry at nominal operating conditions due to limitations in the design process, analysis capability, and computational resources. In the present study, full lifecycle management and assessment during the early stages of design was conducted through the completion of a robustness assessment, in addition to performance analysis, of a prediffuser flow path, strut, and frame in order to identify significant factors influencing performance and cost. Application of Quality Function Deployment (QFD) was utilized to capture the critical-to-quality customer requirements in relation to the functional requirements of the component. Key sources of variation influencing the component were then identified and prioritized based on legacy component service and design experience using robust design (also know as design for process excellence, or design for six sigma) tools. Results from the application of the robust design tools indicate that manufacturing and usage variations are likely to have a larger impact on the aerodynamic performance than structural performance. Aerodynamic analysis of the prediffuser and strut was performed to quantify the sensitivity of the aerodynamic performance to manufacturing and usage variations. Full three-dimensional computational fluid dynamics (CFD) analysis was performed using a series of latin hypercube design of experiments to statistically quantify the variation in the aerodynamic performance metrics of the prediffuser with a strut. It was determined that manufacturing and/or usage variations had a significant impact on the variation in aerodynamic performance. In addition, for some cases the variation in aerodynamic performance resulting from variations in noise factors was greater than those resulting from changes in the strut design parameters.

Design Evaluation Method for Miniature Machine Tools Utilizing Form-Shaping Theory

2003 ◽  
Author(s):  
Nozomu Mishima
Keyword(s):  
Machine Tool ◽  
Conceptual Design ◽  
Machine Tools ◽  
Evaluation Method ◽  
Design Guidelines ◽  
Design Tool ◽  
Design Parameters ◽  
Design Evaluation ◽  
Machine Performance ◽  
Positioning Errors

A microfactory is a system that can perform manufacturing processes within a very limited space such as a desktop. However, design optimization of miniature machine tools in microfactories have not been studied enough. Since the miniature machine tool designs are not supported by existing design experience as normal machine tools are, design guidelines for miniature machine tool are strongly demanded. And a design tool to analyze machine performance without prototyping will be also necessary because the miniature machines have wider design choices than normal machine tools have, based on its small size and less constraints. This paper focuses on a robust design tool combining form-shaping theory with the Taguchi method, to roughly estimate performance of miniature machine tools at its conceptual design stages. The effort not only identifies critical design parameters that have significant influence on the machining tolerance, but also determines which structure has the best theoretical performance. The paper tells that the proposing design evaluation method can help machine tool designers in determining the optimum structure of a miniature machine tool. The study also realizes two designs of miniature mills to measure positioning errors. The measurement ensures the design evaluation method can predict the machine performance well enough for usage in conceptual design stages. The paper concludes that the design evaluation method is applicable to a systematic miniaturization of a machine tool.

scholarly journals Integration of the Response Surface Methodology With the Compromise Decision Support Problem in Developing a General Robust Design Procedure

1995 ◽  
Author(s):  
Wei Chen ◽  
Kwok-Leung Tsui ◽  
Janet K. Allen ◽  
Farrokh Mistree
Keyword(s):  
Decision Support ◽  
Response Surface ◽  
Robust Design ◽  
Irrigation System ◽  
Design Procedure ◽  
Closed Form Solutions ◽  
Control Factors ◽  
Design Variables ◽  
Solar Powered ◽  
Noise Factors

Abstract In this paper we introduce a comprehensive and rigorous robust design procedure to overcome some limitations of the current approaches. A comprehensive approach is general enough to model the two major types of robust design applications, namely, • robust design associated with the minimization of the deviation of performance caused by the deviation of noise factors (uncontrollable parameters), AND • robust design due to the minimization of the deviation of performance caused by the deviation of control factors (design variables). We achieve mathematical rigor by using, as a foundation, principles from the design of experiments and optimization. Specifically, we integrate the Response Surface Method (RSM) with the compromise Decision Support Problem (DSP). Our approach is especially useful for design problems where there are no closed-form solutions and system performance is computationally expensive to evaluate. The design of a solar powered irrigation system is used as an example. Our focus in this paper is on illustrating our approach rather than on the results per se.

Robust Design for Multiscale and Multidisciplinary Applications

2006 ◽  
Vol 128 (4) ◽  
pp. 832-843 ◽  
Author(s):  
Janet K. Allen ◽  
Carolyn Seepersad ◽  
HaeJin Choi ◽  
Farrokh Mistree
Keyword(s):  
Robust Design ◽  
Type I ◽  
Uncertain Information ◽  
Control Factors ◽  
Multiscale Systems ◽  
Design Variables ◽  
Challenges And Opportunities ◽  
Quality Of Products ◽  
Many Sources ◽  
Noise Factors

The intent in robust design is to improve the quality of products and processes by reducing their sensitivity to variations, thereby reducing the effects of variability without removing its sources. Robust design is especially useful for integrating information from designers working at multiple length and time scales. Inevitably this involves the integration of uncertain information. This uncertainty is derived from many sources and robust design may be classified based on these sources—uncertainty in noise or environmental and other noise factors (type I); uncertainty in design variables or control factors (type II); and uncertainty introduce by modeling methods (type III). Each of these types of uncertainty can be mitigated by robust design. Of particular interest are the challenges associated with the design of multidisciplinary and multiscale systems; these challenges and opportunities are examined in the context of materials design.

Improvement of horizontal borer control system

2020 ◽  
Vol 2020 (7) ◽  
pp. 41-48
Author(s):  
Dmitriy Petreshin ◽  
Viktor Khandozhko ◽  
Andrey Dubov ◽  
German Dobrovolsky
Keyword(s):  
Control System ◽  
Machine Tool ◽  
Feed Drive ◽  
Feed Drives ◽  
System Improvement

The control system improvement of a machine-tool is considered. The necessity in control system updating is substantiated. There is shown a procedure for horizontal borer updating. A problem on adjustment of modern digital electrical feed drives is presented. A sample of electrical feed drive and NC device adjustment is presented.

Front steering design guidelines formulation for e-scooters considering the influence of sitting and standing riders on self-stability and safety performance

2021 ◽  
pp. 095440702199217
Author(s):  
Milan Paudel ◽  
Fook Fah Yap
Keyword(s):  
Preventive Measures ◽  
Recent Trend ◽  
Dynamic Performance ◽  
Design Guidelines ◽  
Safety Performance ◽  
Design Parameters ◽  
Single Track ◽  
Standing Posture ◽  
Last Mile ◽  
Current Design

E-scooters are a recent trend and are viewed as a sustainable solution to ease the first and last mile problem in modern transportation. However, an alarming rate of accidents, injuries, and fatalities have caused a significant setback for e-scooters. Many preventive measures and legislation have been put on the e-scooters, but the number of accidents and injuries has not reduced considerably. In this paper, the current design approach of e-scooters has been analyzed, and the most common range of design parameters have been identified. Thereafter, validated mathematical models have been used to quantify the performance of e-scooters and relate them with the safety aspects. Both standing and seated riders on e-scooters have been considered, and their influence on the dynamic performance has been analyzed and compared with the standard 26-in wheel reference safety bicycle. With more than 80% of the accidents and injuries occurring from falling or colliding with obstacles, this paper tries to correlate the dynamics of uncontrolled single-track vehicles with the safety performance of e-scooters. The self-stability, handling, and braking effect have been considered as major performance matrices. The analysis has shown that the current e-scooter designs are not as stable as the reference safety bicycle. Moreover, these e-scooters have been found unstable within the most common range of legislated riding velocity. The results corroborate with the general perception that the current designs of e-scooters are less stable, easy to lose control, twitchy, or wobbly to ride. Furthermore, the standing posture of the rider on the e-scooter has been found dangerous while braking to avoid any disturbances such as potholes or obstacles. Finally, the front steering design guidelines have been proposed to help modify the current design of e-scooters to improve the dynamic performance, hence the safety of the e-scooter riders and the surroundings.

Sign in / Sign up

Export Citation Format

Share Document