Robust parameter design （RPD） is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the c...Robust parameter design （RPD） is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the correspondence relation between fractional factorial RPDs and the blocking schemes for full factorial RPDs. In addition, we provide a construction of optimal blocking schemes that make all main effects and control-by-noise two-factor interactions estimable.展开更多
Robust Parameter Design(RPD) has been widely applied for improving quality and reliability of products.One of the key drawbacks of applying RPD using Taguchi method is that the stable factors may not be independent of...Robust Parameter Design(RPD) has been widely applied for improving quality and reliability of products.One of the key drawbacks of applying RPD using Taguchi method is that the stable factors may not be independent of the adjustment factors, resulting in unsatisfactory design.Moreover, the Taguchi method cannot guarantee global optimality since the levels set in the experiment are usually discrete to ensure orthogonal design.In this paper, robust solutions of the stable factors are obtained via a nonlinear model based on polynomial fitting;while the adjustment factors are obtained via interactions analysis so that they are independent of the stable factors.In particular, the values of the adjustment factors are determined by output offset compensation so as to achieve robustness of the design scheme.An example on the design of an aeronautical electrical apparatus is presented to illustrate the procedure.The results show that the proposed method can take full advantage of the nonlinearity in the response and achieve the desired outcome.展开更多
A water rocket is a rocket system that obtains thrust by injecting water with compressed air of up to about 8 atmospheres. It is usually manufactured using a pressure-resistant PET bottle. The mechanical elements and ...A water rocket is a rocket system that obtains thrust by injecting water with compressed air of up to about 8 atmospheres. It is usually manufactured using a pressure-resistant PET bottle. The mechanical elements and principles contained in the water rocket have much in common with the actual small rocket system, and are suitable as educational and research teaching materials in the field of mechanics. Especially in the field of disaster prevention and mitigation, the use of water rockets is being researched and developed as a rescue tool in the event of a flood or earthquake as a disaster countermeasure. However, since the water rocket is a flying object based on the mechanical principle, it is important to ensure the accuracy and stability of the flight path. In this paper, a mechanical simulator is developed with a numerical calculation program based on the mechanical consideration of water rocket flight performance. In addition, the correlation between the flight distance obtained in the simulation and the estimated flight distance is analyzed by applying a multivariate analysis method and verifying the validity of the flight distance calculated from the result. Based on the verification results, we will apply a statistical optimization method to approach the optimization of flight stability performance conditions for water rockets.展开更多
Several process parameters affect product reliability.Traditional reliability improvement methods primarily focus on maximizing product lifetime,often overlooking the variation in product lifetime.Manufacturers,howeve...Several process parameters affect product reliability.Traditional reliability improvement methods primarily focus on maximizing product lifetime,often overlooking the variation in product lifetime.Manufacturers,however,aim to produce products with minimal variations in their performance.Robust parameter design offers an effective strategy to help manufacturers enhance product reliability while reducing process variations.In practice,reliability experiments frequently involve constrained randomization due to the selection of specific experimental protocols.This study proposes a framework to achieve robust product reliability under a constrained randomization experiment.To consider random effects,we develop a Bayesian method-based Weibull non-linear mixed model for the lifetime response.Important factors are identified according to Bayesian posterior credible intervals.Subsequently,we propose an integrated multi-objective optimization model to determine the optimal factor levels.This model simultaneously considers minimizing the total costs of the manufacturer,maximizing the product lifetime,and minimizing the lifetime variance.An industrial thermostat experiment is conducted to validate the proposed method.Compared to existing approaches,the proposed method demonstrates superior performance in reducing variance and total cost,particularly for long warranty periods.Finally,we discuss the practical implications of the optimal solutions for manufacturers,finding that variations remain tolerable within a certain range.展开更多
A new parameter coordination and robust optimization approach for multidisciplinary design is presented. Firstly, the constraints network model is established to support engineering change, coordination and optimizati...A new parameter coordination and robust optimization approach for multidisciplinary design is presented. Firstly, the constraints network model is established to support engineering change, coordination and optimization. In this model, interval boxes are adopted to describe the uncertainty of design parameters quantitatively to enhance the design robustness. Secondly, the parameter coordination method is presented to solve the constraints network model, monitor the potential conflicts due to engineering changes, and obtain the consistency solution space corresponding to the given product specifications. Finally, the robust parameter optimization model is established, and genetic arithmetic is used to obtain the robust optimization parameter. An example of bogie design is analyzed to show the scheme to be effective.展开更多
Nanogenerators were first demonstrated by deflecting aligned ZnO nanowires using a conductive atomic force microscopy(AFM)tip.The output of a nanogenerator is affected by three parameters:tip normal force,tip scanning...Nanogenerators were first demonstrated by deflecting aligned ZnO nanowires using a conductive atomic force microscopy(AFM)tip.The output of a nanogenerator is affected by three parameters:tip normal force,tip scanning speed,and tip abrasion.In this work,systematic experimental studies have been carried out to examine the combined effects of these three parameters on the output,using statistical design of experiments.A statistical model has been built to analyze the data and predict the optimal parameter settings.For an AFM tip of cone angle 70°coated with Pt,and ZnO nanowires with a diameter of 50 nm and lengths of 600 nm to 1μm,the optimized parameters for the nanogenerator were found to be a normal force of 137 nN and scanning speed of 40μm/s,rather than the conventional settings of 120 nN for the normal force and 30μm/s for the scanning speed.A nanogenerator with the optimized settings has three times the average output voltage of one with the conventional settings.展开更多
Automatic process control (APC) based on design of experiment (DOE) is a cost-efficient approach for variation reduction. The process changes both in mean and variance owing to online parameter adjustment make it hard...Automatic process control (APC) based on design of experiment (DOE) is a cost-efficient approach for variation reduction. The process changes both in mean and variance owing to online parameter adjustment make it hard to apply traditional SPC charts in such DOE-based APC applied process. An adaptive SPC scheme is developed, which can better track the process transitions and achieve the possible SPC run cost reduction when the process is stable. The control law of SPC parameters is designed by fully utilizing the estimation properties of the process model instead of traditionally using the data collected from the production line. An example is provided to illustrate the proposed adaptive SPC design approach.展开更多
Negative Poisson's ratio(NPR) structure has outstanding performances in lightweight and energy absorption, and it can be widely applied in automotive industries. By combining the front anti-collision beam, crash b...Negative Poisson's ratio(NPR) structure has outstanding performances in lightweight and energy absorption, and it can be widely applied in automotive industries. By combining the front anti-collision beam, crash box and NPR structure, a novel NPR bumper system for improving the crashworthiness is first proposed in the work. The performances of the NPR bumper system are detailed studied by comparing to traditional bumper system and aluminum foam filled bumper system. To achieve the rapid design while considering perturbation induced by parameter uncertainties, a multi-objective robust design optimization method of the NPR bumper system is also proposed. The parametric model of the bumper system is constructed by combining the full parametric model of the traditional bumper system and the parametric model of the NPR structure. Optimal Latin hypercube sampling technique and dual response surface method are combined to construct the surrogate models. The multi-objective robust optimization results of the NPR bumper system are then obtained by applying the multi-objective particle swarm optimization algorithm and six sigma criteria. The results yielded from the optimizations indicate that the energy absorption capacity is improved significantly by the NPR bumper system and its performances are further optimized efficiently by the multi-objective robust design optimization method.展开更多
This article considers the problem of selecting two-level designs under the baseline parameterisation when some two-factor interactions are important.We propose a minimum aberration criterion,which minimises the bias ...This article considers the problem of selecting two-level designs under the baseline parameterisation when some two-factor interactions are important.We propose a minimum aberration criterion,which minimises the bias caused by the non-negligible effects.Using this criterion,a class of optimal designs can be further distinguished from one another,and we present an algorithm to find the minimum aberration designs among the D-optimal designs.Sixteen-run and twenty-run designs are summarised for practical use.展开更多
基金supported by the National Natural Science Foundation of China(1127120511271355+2 种基金11101024 and 11171165)the "131" Talents Program of Tianjinthe Fundamental Research Funds for the Central Universities(65030011 and 65011361)
文摘Robust parameter design （RPD） is an important issue in experimental designs. If all experimental runs cannot be performed under homogeneous conditions, blocking the units is effective. In this paper, we obtain the correspondence relation between fractional factorial RPDs and the blocking schemes for full factorial RPDs. In addition, we provide a construction of optimal blocking schemes that make all main effects and control-by-noise two-factor interactions estimable.
基金co-supported by the National Natural Science Foundation of China(Nos.51707044 and 61671172)the China Postdoctoral Science Foundation(No.2018M632377)。
文摘Robust Parameter Design(RPD) has been widely applied for improving quality and reliability of products.One of the key drawbacks of applying RPD using Taguchi method is that the stable factors may not be independent of the adjustment factors, resulting in unsatisfactory design.Moreover, the Taguchi method cannot guarantee global optimality since the levels set in the experiment are usually discrete to ensure orthogonal design.In this paper, robust solutions of the stable factors are obtained via a nonlinear model based on polynomial fitting;while the adjustment factors are obtained via interactions analysis so that they are independent of the stable factors.In particular, the values of the adjustment factors are determined by output offset compensation so as to achieve robustness of the design scheme.An example on the design of an aeronautical electrical apparatus is presented to illustrate the procedure.The results show that the proposed method can take full advantage of the nonlinearity in the response and achieve the desired outcome.
文摘A water rocket is a rocket system that obtains thrust by injecting water with compressed air of up to about 8 atmospheres. It is usually manufactured using a pressure-resistant PET bottle. The mechanical elements and principles contained in the water rocket have much in common with the actual small rocket system, and are suitable as educational and research teaching materials in the field of mechanics. Especially in the field of disaster prevention and mitigation, the use of water rockets is being researched and developed as a rescue tool in the event of a flood or earthquake as a disaster countermeasure. However, since the water rocket is a flying object based on the mechanical principle, it is important to ensure the accuracy and stability of the flight path. In this paper, a mechanical simulator is developed with a numerical calculation program based on the mechanical consideration of water rocket flight performance. In addition, the correlation between the flight distance obtained in the simulation and the estimated flight distance is analyzed by applying a multivariate analysis method and verifying the validity of the flight distance calculated from the result. Based on the verification results, we will apply a statistical optimization method to approach the optimization of flight stability performance conditions for water rockets.
基金supported by the National Natural Science Foundation of China[grants numbers:72002066,71871204,72471172,and 71902138]。
文摘Several process parameters affect product reliability.Traditional reliability improvement methods primarily focus on maximizing product lifetime,often overlooking the variation in product lifetime.Manufacturers,however,aim to produce products with minimal variations in their performance.Robust parameter design offers an effective strategy to help manufacturers enhance product reliability while reducing process variations.In practice,reliability experiments frequently involve constrained randomization due to the selection of specific experimental protocols.This study proposes a framework to achieve robust product reliability under a constrained randomization experiment.To consider random effects,we develop a Bayesian method-based Weibull non-linear mixed model for the lifetime response.Important factors are identified according to Bayesian posterior credible intervals.Subsequently,we propose an integrated multi-objective optimization model to determine the optimal factor levels.This model simultaneously considers minimizing the total costs of the manufacturer,maximizing the product lifetime,and minimizing the lifetime variance.An industrial thermostat experiment is conducted to validate the proposed method.Compared to existing approaches,the proposed method demonstrates superior performance in reducing variance and total cost,particularly for long warranty periods.Finally,we discuss the practical implications of the optimal solutions for manufacturers,finding that variations remain tolerable within a certain range.
基金This project is supported by National Natural Science Foundation of China (No.60304015, No.50575142).
文摘A new parameter coordination and robust optimization approach for multidisciplinary design is presented. Firstly, the constraints network model is established to support engineering change, coordination and optimization. In this model, interval boxes are adopted to describe the uncertainty of design parameters quantitatively to enhance the design robustness. Secondly, the parameter coordination method is presented to solve the constraints network model, monitor the potential conflicts due to engineering changes, and obtain the consistency solution space corresponding to the given product specifications. Finally, the robust parameter optimization model is established, and genetic arithmetic is used to obtain the robust optimization parameter. An example of bogie design is analyzed to show the scheme to be effective.
基金This research was supported by the Basic Energy Science,U.S.Department of Energy(BES DOE)(No.DE-FG02-07ER46394)the National Science Foundation(NSF)(Nos.DMS0706436,CMMI 0403671)。
文摘Nanogenerators were first demonstrated by deflecting aligned ZnO nanowires using a conductive atomic force microscopy(AFM)tip.The output of a nanogenerator is affected by three parameters:tip normal force,tip scanning speed,and tip abrasion.In this work,systematic experimental studies have been carried out to examine the combined effects of these three parameters on the output,using statistical design of experiments.A statistical model has been built to analyze the data and predict the optimal parameter settings.For an AFM tip of cone angle 70°coated with Pt,and ZnO nanowires with a diameter of 50 nm and lengths of 600 nm to 1μm,the optimized parameters for the nanogenerator were found to be a normal force of 137 nN and scanning speed of 40μm/s,rather than the conventional settings of 120 nN for the normal force and 30μm/s for the scanning speed.A nanogenerator with the optimized settings has three times the average output voltage of one with the conventional settings.
基金the National Natural Science Foundation of China (50405016 70671065).
文摘Automatic process control (APC) based on design of experiment (DOE) is a cost-efficient approach for variation reduction. The process changes both in mean and variance owing to online parameter adjustment make it hard to apply traditional SPC charts in such DOE-based APC applied process. An adaptive SPC scheme is developed, which can better track the process transitions and achieve the possible SPC run cost reduction when the process is stable. The control law of SPC parameters is designed by fully utilizing the estimation properties of the process model instead of traditionally using the data collected from the production line. An example is provided to illustrate the proposed adaptive SPC design approach.
基金supported by the National Natural Science Foundation of China(Grant Nos.51605219&51375007)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20160791&SBK2015022352)+1 种基金the Visiting Scholar Foundation of the State Key Lab of Mechanical Transmission in Chongqing University(Grant Nos.SKLMT-KFKT-201608,SKLMTKFKT-2014010&SKLMT-KFKT-201507)the Fundamental Research Funds for the Central Universities(Grant No.NE2016002)
文摘Negative Poisson's ratio(NPR) structure has outstanding performances in lightweight and energy absorption, and it can be widely applied in automotive industries. By combining the front anti-collision beam, crash box and NPR structure, a novel NPR bumper system for improving the crashworthiness is first proposed in the work. The performances of the NPR bumper system are detailed studied by comparing to traditional bumper system and aluminum foam filled bumper system. To achieve the rapid design while considering perturbation induced by parameter uncertainties, a multi-objective robust design optimization method of the NPR bumper system is also proposed. The parametric model of the bumper system is constructed by combining the full parametric model of the traditional bumper system and the parametric model of the NPR structure. Optimal Latin hypercube sampling technique and dual response surface method are combined to construct the surrogate models. The multi-objective robust optimization results of the NPR bumper system are then obtained by applying the multi-objective particle swarm optimization algorithm and six sigma criteria. The results yielded from the optimizations indicate that the energy absorption capacity is improved significantly by the NPR bumper system and its performances are further optimized efficiently by the multi-objective robust design optimization method.
基金supported by Natural Sciences and Engineering Research Council of Canada[Discovery Grant].
文摘This article considers the problem of selecting two-level designs under the baseline parameterisation when some two-factor interactions are important.We propose a minimum aberration criterion,which minimises the bias caused by the non-negligible effects.Using this criterion,a class of optimal designs can be further distinguished from one another,and we present an algorithm to find the minimum aberration designs among the D-optimal designs.Sixteen-run and twenty-run designs are summarised for practical use.
