Spacecraft design optimization using Taguchi analysis

The quality engineering methods of Dr. Genichi Taguchi, employing design of experiments, are important statistical tools for designing high quality systems at reduced cost. The Taguchi method was utilized to study several simultaneous parameter level variations of a lunar aerobrake structure to arrive at the lightest weight configuration. Finite element analysis was used to analyze the unique experimental aerobrake configurations selected by Taguchi method. Important design parameters affecting weight and global buckling were identified and the lowest weight design configuration was selected

Weight optimization of an aerobrake structural concept for a lunar transfer vehicle

An aerobrake structural concept for a lunar transfer vehicle was weight optimized through the use of the Taguchi design method, finite element analyses, and element sizing routines. Six design parameters were chosen to represent the aerobrake structural configuration. The design parameters included honeycomb core thickness, diameter-depth ratio, shape, material, number of concentric ring frames, and number of radial frames. Each parameter was assigned three levels. The aerobrake structural configuration with the minimum weight was 44 percent less than the average weight of all the remaining satisfactory experimental configurations. In addition, the results of this study have served to bolster the advocacy of the Taguchi method for aerospace vehicle design. Both reduced analysis time and an optimized design demonstrated the applicability of the Taguchi method to aerospace vehicle design

Optimization of Friction Stir Welding Parameters of AA5052-H32 Aluminium Alloy using Taguchi and Taguchi-Pareto Methods

It is difficult to improve the quality of friction stir welded joints of AA5052-H32 material because of scarce metrics on its concurrent optimization and prioritization. However, the objective of this article is to obtain optimal parametric values and identify important parameters using the Taguchi-Pareto method during the friction stir welding process of AA5052-H32 material. Then the ranks, delta values and optimal parameters are determined. The critical parameters identified for the friction stir welding process are the tool pin, rotational speed, welding speed and tool angle. When comparing the results of these parameters using the Taguchi method and Taguchi-Pareto method, the rotational speed retained its first position in both methods; the tool tilt angle gained the second position in the Taguchi-Pareto method from its third position when only the Taguchi method was considered. The welding speed became the third position in the Taguchi-Pareto method against the second position that it had in the Taguchi method. However, the tool pin profile retained its last position in both methods. Consequently, the rotational speed is the best parameter while the tool pin profile is the worst parameter. For the Taguchi-Pareto method, the optimal parametric setting is TPP2/TPP4RS1WS4TTA3. This is interpreted as cylindrical tapered or square tapered for the tool profile, 40 rpm of rotational speed, 75 mm/min of welding speed and 1.5° of tool tilt angle. The novelty of this study is the scope of analysis of the AA5052-H32 material that extends beyond the Taguchi method to the Taguchi-Pareto method where the concurrent optimization and prioritization of friction welding parameters are achieved

Hybrid optimisation electromagnetic interference shielding effectiveness:mechanical and physical performance of plaster mortar containing palm oil fuel ash using taguchi grey and taguchi-flower pollination algorithm methods

The rapid development of wireless telecommunications has revolutionarily modernized the global society, whereas it has created serious concerns on harmful effects of the electromagnetic interference (EMI) on human health and performance of electronic devices. The purpose of this research was to use palm oil fuel ash (POFA) as cement filler in plastering mortar to overcome the EMI issue. This research adopted Taguchi method with mix level design (L16 (44 22)) to examined the EMI shielding effectiveness (SE), mechanical properties and physical properties of the mortar. Six factors namely POFA admixture percentage, topcoat powder /binder ratio (TP/B), water/binder ratio (W/B), latex agent content (LA), the particle size of POFA and curing condition are used to control the nine responses. Pre-experiment data is optimized based on Taguchi-grey and Flower Pollination Algorithm (FPA) methods. The feasibility of the optimization was evaluated by repeating the experiments. Initially, the POFA was refined and segregated into 4 different layers. Layer 1 POFA performed highest SE with 25.76 dB at 1 GHz where the SE was decreased in accordance with the sequence of POFA layers. The SEM image of POFA showed the existence of cenosphere particles and it has potential in EMI SE due to the hollow spherical shape. Regression and ANOVA analysis demonstrated the optimal mixture from Taguchi-grey method is able to give additional 6 dB of SE compare to plaster mortar without POFA. Meanwhile, the optimal mixture from Taguchi-FPA able to give additional 5 dB of SE. It’s found that this does not affect its mechanical and physical properties because the confirmation results proved that all responses are within the range that specified in the standards. Finally, this research successfully employed POFA as cement filler for plastering mortar which can mitigate the EMI. The increase in the SE is due to the carbon content and spherical cenosphere particle in the POFA that promote multiple reflections. The implementation of Taguchi-grey and Taguchi-FPA methods successfully obtained optimal factors in order to improve SE and remaining protection of mechanical and physical properties in plaster mortar

Novel EDAS-Taguchi and EDAS-Taguchi-Pareto Methods for Wire EDM Process Parametric Selection of Ni55.8Ti (Nitinol) Shape Memory Alloy

The EDAS (evaluation based on distance from average solution) method is a broadly utilized tool for multi-criteria analysis with the ability to handle several conflicting criteria. The Taguchi method is an optimization tool with economic capability in experimentation. This article presents EDAS Taguchi (EDAS-T) method based on EDAS and the Taguchi method. It also presents EDAS Taguchi-Pareto (EDAS-TP) method framed from EDAS and Taguchi-Pareto methods. Furthermore, data from the literature to test the proposed methods are presented, which the results are compared. This research shows that the EDAS method produces the optimum combination of parameters at a run with a current of 4A, pulse on time of 50 µs, pulse off time of 14ms, and powder concentration of 1 g/L. Also, the EDAS-Taguchi method reveals a current of 4A, pulse on time of 60 µs, pulse off time of 14 µs, and powder concentration of 1 g/L. However, the principal result is that using the EDAS Taguchi-Pareto method, the optimal current is 3A, pulse on time is 60 µs, and powder concentration is 0.75g/L. The EDAS Taguchi-Pareto method eliminated the pulse off time and pulse on time, claiming that it is not significant to the system's optimum performance. The principal novelty of this article is that it introduces a mechanism of concurrently optimizing and selecting the wire EDM process parameters using the EDAS-Taguchi-Pareto method. The optimization is parallelly conducted as selection occurs, providing an initial notification to ascertain timely detection and control of local optimality of parameters to global optimization before final selection. This is unlike most evaluations, where optimization is done differently from the selection. This study is the first to develop and use EDAS methods for the WEDM process of Ni55.8Ti shape memory alloy

A Comparative Analysis of Three Optimisation Approaches to Free Swell Characterisation of Particulate Coconut Shell Reinforcement Composite Material

There is paucity of data relating to the free swell properties of composite reinforcement materials in outdoor applications despite their undesirable tendency to absorb water. In this paper, a comparative performance analysis of three optimisation models - Taguchi method, simplex algorithm and Taguchi-simplex method - is pursued. We used experimental data of 0.600 mm particulate coconut shell with L27 (311) orthogonal arrays of the Taguchi method. For the Taguchi-simplex method, S/N ratios were used as the objective function that the simplex algorithm optimised. Parameters include initial and final volumes of coconut shell particulates (CSPs), mass of water, volumes of CSP and water as well as mass of CSP. The optimised Taguchi method yielded initial and final volumes of 10 and 34 cm3, respectively while it gave the optimal mass of water as 141.54 g. Also, 152 cm3 was the optimal volume of CSP and water while the mass of CSP was optimised to 12.07 g with the use of Taguchi method. However, the use of simplex method retained the initial values of 20 cm3, 34 cm3, 146.81 g, 153 cm3 and 12.07 g as optimal values for the initial and final volumes, mass of water, volume of CSP and water as well as mass of CSP, respectively. The use of Taguchi-simplex method yielded optimal initial and final volumes of 16.6 and 24.82 cm3, respectively. Also, the mass of water was optimal at 92.49 g while the volume of CSP and water was optimal at 107.1 cm3. Lastly, the optimal value for the mass of CSP was obtained at 6.28 g. Confirmatory test validated the results. In conclusion, the optimum parametric setting of the Taguchi-simplex method was the best

Parametrical optimization of laser surface alloyed NiTi shape memory alloy with Co and Nb by the Taguchi method

Different high-purity metal powders were successfully alloyed on to a nickel titanium (NiTi) shape memory alloy (SMA) with a 3 kW carbon dioxide (CO2) laser system. In order to produce an alloyed layer with complete penetration and acceptable composition profile, the Taguchi approach was used as a statistical technique for optimizing selected laser processing parameters. A systematic study of laser power, scanning velocity, and pre-paste powder thickness was conducted. The signal-to-noise ratios (S/N) for each control factor were calculated in order to assess the deviation from the average response. Analysis of variance (ANOVA) was carried out to understand the significance of process variables affecting the process effects. The Taguchi method was able to determine the laser process parameters for the laser surface alloying technique with high statistical accuracy and yield a laser surface alloying technique capable of achieving a desirable dilution ratio. Energy dispersive spectrometry consistently showed that the per cent by weight of Ni was reduced by 45 per cent as compared with untreated NiTi SMA when the Taguchi-determined laser processing parameters were employed, thus verifying the laser's processing parameters as optimum

INCORPORATING SERVQUAL-QFD WITH TAGUCHI DESIGN FOR OPTIMIZING SERVICE QUALITY DESIGN

Deploying good service design in service companies has been updated issue in improving customer satisfaction, especially based on the level of service quality measured by Parasuraman’s SERVQUAL. Many researchers have been proposing methods in designing the service, and some of them are based on engineering viewpoint, especially by implementing the QFD method or even using robust Taguchi method. The QFD method would found the qualitative solution by generating the “how’s”, while Taguchi method gives more quantitative calculation in optimizing best solution. However, incorporating both QFD and Taguchi has been done in this paper and yields better design process. The purposes of this research is to evaluate the incorporated methods by implemented it to a case study, then analyze the result and see the robustness of those methods to customer perception of service quality. Started by measuring service attributes using SERVQUAL and find the improvement with QFD, the deployment of QFD solution then generated by defining Taguchi factors levels and calculating the Signal-to-noise ratio in its orthogonal array, and optimized Taguchi response then found. A case study was given for designing service in local bank. Afterward, the service design obtained from previous analysis was then evaluated and shows that it was still meet the customer satisfaction. Incorporating QFD and Taguchi has performed well and can be adopted and developed for another research for evaluating the robustness of result