Zhang, Y, Liu, Q, He, Z, Zong, Z & Fang, J 2019, 'Dynamic impact response of aluminum honeycombs filled with Expanded Polypropylene foam', COMPOSITES PART B-ENGINEERING, vol. 156, pp. 17-27.View/Download from: Publisher's site
Wu, C, Fang, J & Li, Q 2019, 'Multi-material topology optimization for thermal buckling criteria', Computer Methods in Applied Mechanics and Engineering, vol. 346, pp. 1136-1155.View/Download from: UTS OPUS or Publisher's site
© 2018 Elsevier B.V. The structures in thermal environment often suffer from severe thermal expansion, potentially leading to buckling failure. This study aims to address this issue by proposing multi-material topology optimization for thermomechanical buckling problems. The density-based model with the rational approximation of material properties (RAMP) is adopted here for parameterization of multiple materials. The sensitivities of thermomechanical compliance and buckling are derived through the adjoint technique. The globally convergent version of the method of moving asymptotes (GCMMA) is employed to solve the non-monotonic topology optimization problem. In this study, two numerical examples are presented to illustrate the effectiveness of the proposed method, in which the total volume of multi-materials is minimized subject to thermoelastic compliance and buckling constraints. The examples exhibit significant difference in the final topologies for mechanical buckling and thermomechanical buckling optimization. The study demonstrates the importance of thermomechanical buckling criteria for the design of structures operating in a temperature-varying environment.
Fu, J, Liu, Q, Liufu, K, Deng, Y, Fang, J & Li, Q 2019, 'Design of bionic-bamboo thin-walled structures for energy absorption', THIN-WALLED STRUCTURES, vol. 135, pp. 400-413.View/Download from: Publisher's site
Liu, T, Sun, G, Fang, J, Zhang, J & Li, Q 2019, 'Topographical design of stiffener layout for plates against blast loading using a modified ant colony optimization algorithm', STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, vol. 59, no. 2, pp. 335-350.View/Download from: Publisher's site
Xu, Y, Gao, Y, Wu, C, Fang, J & Li, Q 2019, 'Robust topology optimization for multiple fiber-reinforced plastic (FRP) composites under loading uncertainties', Structural and Multidisciplinary Optimization, vol. 59, no. 3, pp. 695-711.View/Download from: Publisher's site
© 2019, Springer-Verlag GmbH Germany, part of Springer Nature. This study proposes a non-deterministic robust topology optimization of ply orientation for multiple fiber-reinforced plastic (FRP) materials, such as carbon fiber–reinforced plastic (CFRP) and glass fiber–reinforced plastic (GFRP) composites, under loading uncertainties with both random magnitude and random direction. The robust topology optimization is considered here to minimize the fluctuation of structural performance induced by load uncertainty, in which a joint cost function is formulated to address both the mean and standard deviation of compliance. The sensitivities of the cost function are derived with respect to the design variables in a non-deterministic context. The discrete material optimization (DMO) technique is extended here to accommodate robust topology optimization for FRP composites. To improve the computational efficiency, the DMO approach is revised to reduce the number of design variables by decoupling the selection of FRP materials and fiber orientations. In this study, four material design examples are presented to demonstrate the effectiveness of the proposed methods. The robust topology optimization results exhibit that the composite structures with the proper ply orientations are of more stable performance when the load fluctuates.
Wu, C, Gao, Y, Fang, J, Lund, E & Li, Q 2019, 'Simultaneous Discrete Topology Optimization of Ply Orientation and Thickness for Carbon Fiber Reinforced Plastic-Laminated Structures', Journal of Mechanical Design, Transactions of the ASME, vol. 141, no. 4.View/Download from: Publisher's site
© 2019 by ASME. This study developed a discrete topology optimization procedure for the simultaneous design of ply orientation and thickness for carbon fiber reinforced plastic (CFRP)-laminated structures. A gradient-based discrete material and thickness optimization (DMTO) algorithm was developed by using casting-based explicit parameterization to suppress the intermediate void across the thickness of the laminate. A benchmark problem was first studied to compare the DMTO approach with the sequential three-phase design method using the free size, ply thickness, and stacking sequence of the laminates. Following this, the DMTO approach was applied to a practical design problem featuring a CFRP-laminated engine hood by minimizing overall compliance subject to volume-related and functional constraints under multiple load cases. To verify the optimized design, a prototype of the CFRP engine hood was created for experimental tests. The results showed that the simultaneous discrete topology optimization of ply orientation and thickness was an effective approach for the design of CFRP-laminated structures.
Liu, J, Wu, C, Li, J, Fang, J, Su, Y & Shao, R 2019, 'Ceramic balls protected ultra-high performance concrete structure against projectile impact-A numerical study', INTERNATIONAL JOURNAL OF IMPACT ENGINEERING, vol. 125, pp. 143-162.View/Download from: Publisher's site
Chen, S, Yu, H & Fang, J 2018, 'A novel multi-cell tubal structure with circular corners for crashworthiness', Thin-Walled Structures, vol. 122, pp. 329-343.View/Download from: UTS OPUS or Publisher's site
© 2017 Elsevier Ltd Multi-cell structures have proven to own excellent energy absorbing capability and lightweight effect in the automotive and aerospace industries. The cross-sectional configuration of the multi-cell structure has a significant effect on crashworthiness. Unlike existing multi-cell tubes, a new type of five-cell profile with four circular elements at the corners (C5C) was proposed in this study. To investigate the crashworthiness of the new C5C tube, finite element (FE) models were first established by using the nonlinear finite element code LS-DYNA and validated with experimental results. Following that, the comparison of the C5C tube and other multi-cell tubes with the same mass was conducted to quantify the relative merits of the C5C tube. Then, a detailed study was performed to analyze the effect of the corner-cell size and wall thickness. Finally, the optimization design was carried out to seek the optimal structure. The results showed that the new multi-cell structure can absorb much more crash energy than other four types of tubes. Moreover, the energy absorption of this new multi-cell tube C5C was affected by the corner-cell size and wall thickness significantly. A proper corner-cell size and slightly thicker internal ribs were recommended. In addition, the multi-objective particle swarm optimization (MOPSO) algorithm and radial basis function (RBF) surrogate model can optimize the structure effectively. The outcomes of the present study will facilitate the design of multi-cell structures with better crashworthiness.
Sun, G, Liu, T, Fang, J, Steven, GP & Li, Q 2018, 'Configurational optimization of multi-cell topologies for multiple oblique loads', Structural and Multidisciplinary Optimization, vol. 57, no. 2, pp. 469-488.View/Download from: UTS OPUS or Publisher's site
© 2017, Springer-Verlag GmbH Germany. Multi-cell thin-walled structures exhibit significant advantages in maximizing energy absorption and minimizing mass during vehicle crashes. Since the topological distribution of wall members has an appreciable effect on the crashworthiness, their design signifies an important area of research. As a major energy absorber, multi-cell tubes are more commonly encounter oblique loading in real life. Thus, this study aimed to optimize multi-cell cross-sectional configuration of tubal structures for multiple oblique loading cases. An integer coded genetic algorithm (ICGA) is introduced here to optimize topological distribution of multi-celled web members for single/multiple oblique impacting conditions. Specifically, material distribution in a form of allocating web wall thickness, starting from zero, is considered as design variables and maximization of energy absorption (EA) as the design objective under the predefined peak crushing force and structural mass constraints. The optimization allows generating uniform or non-uniform thickness distribution in different web wall configurations to maximize usage efficiency of material. Compared with the baseline structure, the optimized configurations largely improved the energy absorption in both single and multiple load cases. The examples demonstrate that the proposed ICGA-based design method not only provides a useful approach to searching for novel crashworthy structures in a systematic fashion, but also develops a series of novel multi-cell topologies for multiple oblique loading cases.
Wu, Y, Li, W, Fang, J & Lan, Q 2018, 'Multi-objective robust design optimization of fatigue life for a welded box girder', Engineering Optimization, vol. 50, no. 8, pp. 1252-1269.View/Download from: UTS OPUS or Publisher's site
© 2017 Informa UK Limited, trading as Taylor & Francis Group To reduce the scatter of fatigue life for welded structures, a robust optimization method is presented in this study based on a dual surrogate modelling and multi-objective particle swam optimization algorithm. Considering the perturbations of material parameters and environment variables, the mean and standard deviation of fatigue life are fitted using dual surrogate modelling and selected as the objective function to be minimized. As an example, a welded box girder is presented to reduce the standard deviation of fatigue life. A set of non-dominated solutions is produced through a multi-objective particle swam optimization algorithm. A cognitive approach is used to select the optimum solution from the Pareto sets. As a comparative study, traditional single objective optimizations are also presented in this study. The results reduced the standard deviation of the fatigue life by about 16.5%, which indicated that the procedure improved the robustness of the fatigue life.
Qiu, N, Park, C, Gao, Y, Fang, J, Sun, G & Kim, NH 2018, 'Sensitivity-Based Parameter Calibration and Model Validation under Model Error', Journal of Mechanical Design, vol. 140, no. 1, pp. 1-9.View/Download from: UTS OPUS or Publisher's site
© 2018 by ASME. In calibrating model parameters, it is important to include the model discrepancy term in order to capture missing physics in simulation, which can result from numerical, measurement, and modeling errors. Ignoring the discrepancy may lead to biased calibration parameters and predictions, even with an increasing number of observations. In this paper, a simple yet efficient calibration method is proposed based on sensitivity information when the simulation model has a model error and/or numerical error but only a small number of observations are available. The sensitivity-based calibration method captures the trend of observation data by matching the slope of simulation predictions and observations at different designs and then utilizing a constant value to compensate for the model discrepancy. The sensitivity-based calibration is compared with the conventional least squares calibration method and Bayesian calibration method in terms of parameter estimation and model prediction accuracies. A cantilever beam example, as well as a honeycomb tube crush example, is used to illustrate the calibration process of these three methods. It turned out that the sensitivity-based method has a similar performance with the Bayesian calibration method and performs much better than the conventional method in parameter estimation and prediction accuracy.
Fang, J, Sun, G, Qiu, N, Pang, T, Li, S & Li, Q 2018, 'On hierarchical honeycombs under out-of-plane crushing', International Journal of Solids and Structures, vol. 135, pp. 1-13.View/Download from: UTS OPUS or Publisher's site
© 2017 Hierarchy has been introduced to honeycomb structures in pursuing ultralight materials with outstanding mechanical properties. Nevertheless, the hierarchical honeycombs under the out-of-plane loads have not been well studied experimentally and analytically for energy absorption to date. This study aimed to apply a special structural hierarchy to the honeycomb by replacing the sides of hexagons with smaller hexagons. The quasi-static test of the hierarchical honeycomb specimen was first conducted experimentally to investigate the crushing behaviours; and then the corresponding finite element (FE) analyses were performed. Finally, the analytical solutions to the mean crushing force and plateau stress were derived based on the simplified super folding element (SSFE) method. It was shown that the experimental data and numerical results agreed well in terms of crushing force versus displacement relation and energy absorption characteristics; and the analytical results were validated by the experimental test. Importantly, the hierarchy could improve the energy absorption; and the increase in the order and number of replacement hexagons could excavate the advantage even further. Specifically, the second order honeycomb characterized by five smaller replacement hexagons at each order can yield a plateau stress 2.63 and 4.16 times higher than the regular honeycomb and the aluminium foam, respectively. While it might lead to global bending, structural hierarchy provides new architectural configurations for developing novel ultralight materials with exceptional energy absorption capacity under out-of-plane loads.
Qiu, N, Gao, Y, Fang, J, Sun, G & Kim, NH 2018, 'Topological design of multi-cell hexagonal tubes under axial and lateral loading cases using a modified particle swarm algorithm', Applied Mathematical Modelling, vol. 53, pp. 567-583.View/Download from: UTS OPUS or Publisher's site
© 2017 Elsevier Inc. Multi-cell structures have widely been studied due to their excellent energy absorption ability. However, few systematic studies have been conducted on the topological design of cross-sectional configurations of thin-walled tubes. To make full use of the material, topology optimization of multi-cell hexagonal tubes was conducted under both axial compression and lateral bending loadings. A binary particle swarm optimization (PSO) was enhanced by introducing the mass constraint factor to guide the movement of particles, which could improve the success rate of obtaining the global optimum. It was found that the optimum designs under the axial load placed the material outward to strengthen the interaction between the outer and inner walls and created more partitions between the inside rib walls. While under the lateral load, all the optimum designs have diagonally-connected elements to resist local deformation, and the material was also placed outward to increase the moment of inertia and thus to resist the global deformation. For the multiple loading cases, the final optimal designs are similar to the compression designs or combined designs from the two loading cases.
Sun, G, Zhang, H, Fang, J, Li, G & Li, Q 2018, 'A new multi-objective discrete robust optimization algorithm for engineering design', Applied Mathematical Modelling, vol. 53, pp. 602-621.View/Download from: UTS OPUS or Publisher's site
© 2017 Elsevier Inc. This paper proposes a novel multi-objective discrete robust optimization (MODRO) algorithm for design of engineering structures involving uncertainties. In the present MODRO procedure, grey relational analysis (GRA), coupled with principal component analysis (PCA), was used as a multicriteria decision making model for converting multiple conflicting objectives into one unified cost function. The optimization process was iterated using the successive Taguchi approach to avoid the limitation that the conventional Taguchi method fails to deal with a large number of design variables and design levels. The proposed method was first verified by a mathematical benchmark example and a ten-bar truss design problem; and then it was applied to a more sophisticated design case of full scale vehicle structure for crashworthiness criteria. The results showed that the algorithm is able to achieve an optimal design in a fairly efficient manner attributable to its integration with the multicriteria decision making model. Note that the optimal design can be directly used in practical applications without further design selection. In addition, it was found that the optimum is close to the corresponding Pareto frontier generated from the other approaches, such as the non-dominated sorting genetic algorithm II (NSGA-II), but can be more robust as a result of introduction of the Taguchi method. Due to its independence on metamodeling techniques, the proposed algorithm could be fairly promising for engineering design problems of high dimensionality.
Ma, C, Chen, C, Li, Q, Gao, H, Kang, Q, Fang, J, Cui, H, Teng, K & Lv, X 2018, 'Analytical Calculation of No-Load Magnetic Field of External Rotor Permanent Magnet Brushless Direct Current Motor Used as In-Wheel Motor of Electric Vehicle', IEEE Transactions on Magnetics, vol. 54, no. 4.View/Download from: UTS OPUS or Publisher's site
© 1965-2012 IEEE. An analytical method for calculating the no-load magnetic field of external rotor permanent magnet brushless direct current motor (PMBLDCM) used as in-wheel motor of electric vehicle in the stator static coordinate and the rotor motion coordinate is presented in this paper. First, the analytic formulas of slotless permanent magnetic field in both coordinate systems are derived, respectively. Then, the complex relative permeance of external rotor PMBLDCM in both coordinate systems is calculated. Finally, the analytical solution of the no-load magnetic field in both coordinate systems is derived by applying the magnetic potential multiplied by the complex relative permeance. In this paper, a 46-pole-51-slot external rotor PMBLDCM is taken as an example, and the accuracy of the proposed analytical model is verified by the finite-element results. Based on the analytical model, the influences of the stator slotting effect on the no-load magnetic field of the external rotor and the inner stator are analyzed. The spatial order characteristics and frequency characteristics of the no-load magnetic field of the external rotor PMBLDCM in both coordinate systems are revealed, respectively.
Liu, Q, Shen, H, Wu, Y, Xia, Z, Fang, J & Li, Q 2018, 'Crash responses under multiple impacts and residual properties of CFRP and aluminum tubes', COMPOSITE STRUCTURES, vol. 194, pp. 87-103.View/Download from: UTS OPUS or Publisher's site
Qiu, N, Gao, Y, Fang, J, Sun, G, Li, Q & Kim, NH 2018, 'Crashworthiness optimization with uncertainty from surrogate model and numerical error', THIN-WALLED STRUCTURES, vol. 129, pp. 457-472.View/Download from: UTS OPUS or Publisher's site
Wu, Y, Fang, J, He, Y & Li, W 2018, 'Crashworthiness of hierarchical circular-joint quadrangular honeycombs', THIN-WALLED STRUCTURES, vol. 133, pp. 180-191.View/Download from: UTS OPUS or Publisher's site
Sun, G, Zhang, H, Fang, J, Li, G & Li, Q 2017, 'Multi-objective and multi-case reliability-based design optimization for tailor rolled blank (TRB) structures', Structural and Multidisciplinary Optimization, vol. 55, no. 5, pp. 1899-1916.View/Download from: UTS OPUS or Publisher's site
© 2016 Springer-Verlag Berlin HeidelbergLight weight and crashworthiness signify two main challenges facing in vehicle industry, which often conflict with each other. In order to achieve light weight while improving crashworthiness, tailor rolled blank (TRB) has become one of the most potential lightweight technologies. To maximize the characteristics of TRB structures, structural optimization has been adopted extensively. Conventional optimization studies have mainly focused on a single loading case (SLC). In practice, however, engineering structures are often subjected to multiple loading cases (MLC), implying that the optimal design under a certain condition may no longer be an optimum under other loading cases. Furthermore, traditional deterministic optimization could become less meaningful or even unacceptable when uncertainties of design variables and noises of system parameters are present. To address these issues, a multi-objective and multi-case reliability-based design optimization (MOMCRBDO) was developed in this study to optimize the TRB hat-shaped structure. The radial basis function (RBF) metamodel was adopted to approximate the responses of objectives and constraints, the non-dominated sorting genetic algorithm II (NSGA-II), coupled with Monte Carlo Simulation (MCS), was employed to seek optimal reliability solutions. The optimal results show that the proposed method is not only capable of improving the reliability of Pareto solutions, but also enhancing the robustness under MLC.
Fang, J, Sun, G, Qiu, N, Kim, NH & Li, Q 2017, 'On design optimization for structural crashworthiness and its state of the art', Structural and Multidisciplinary Optimization, vol. 55, no. 3, pp. 1091-1119.View/Download from: UTS OPUS or Publisher's site
© 2016 Springer-Verlag Berlin HeidelbergOptimization for structural crashworthiness and energy absorption has become an important topic of research attributable to its proven benefits to public safety and social economy. This paper provides a comprehensive review of the important studies on design optimization for structural crashworthiness and energy absorption. First, the design criteria used in crashworthiness and energy absorption are reviewed and the surrogate modeling to evaluate these criteria is discussed. Second, multiobjective optimization, optimization under uncertainties and topology optimization are reviewed from concepts, algorithms to applications in relation to crashworthiness. Third, the crashworthy structures are summarized, from generically novel structural configurations to industrial applications. Finally, some conclusions and recommendations are provided to enable academia and industry to become more aware of the available capabilities and recent developments in design optimization for structural crashworthiness and energy absorption.
Sun, G, Pang, T, Fang, J, Li, G & Li, Q 2017, 'Parameterization of criss-cross configurations for multiobjective crashworthiness optimization', International Journal of Mechanical Sciences, vol. 124-125, pp. 145-157.View/Download from: UTS OPUS or Publisher's site
© 2017 Elsevier Ltd Thin-walled tubes have exhibited extraordinary advantages in lightweight and energy absorption for crashing scenarios. Geometric configuration of such tubal structures is of decisive effects on crashing behaviors. In this study, crashing characteristics of conventional square tube and a criss-cross tube were first conducted using both experimental and numerical analyses, through which the finite element (FE) models were well validated. It was also revealed that the energy absorption of the criss-cross sectional tube was about 150% higher than that of square column with the same weight. Further, a range of criss-cross sections were parametrically modeled with spline curves and a parametric study was subsequently performed to explore the effects of different parameterized shapes on crashing characteristics. It was found that the geometric parameters significantly affected crashworthiness of the criss-cross tubes, and the criss-cross tubes with a spline curve (CCT_SPL) surpass the criss-cross tubes with a straight line (CCT_STR) in crashworthiness with the same weight. Finally, to optimize the crashwo rthiness of parameterized criss-cross tubes, the non-dominated sorting genetic algorithm II (NSGA-II) was adopted to seek optimal criss-cross shapes for improving specific energy absorption (SEA) and reducing the peak crashing force (F max ), simultaneously. The optimization results indicate that the CCT_SPL profiles with reasonable geometric parameters are superior to the CCT_STR counterparts with an increase of 11.1% in specific energy absorption.
Fang, J, Qiu, N, An, X, Xiong, F, Sun, G & Li, Q 2017, 'Crashworthiness design of a steel-aluminum hybrid rail using multi-response objective-oriented sequential optimization', ADVANCES IN ENGINEERING SOFTWARE, vol. 112, pp. 192-199.View/Download from: UTS OPUS or Publisher's site
Fang, J, Sun, G, Qiu, N, Steven, GP & Li, Q 2017, 'Topology Optimization of Multicell Tubes Under Out-of-Plane Crushing Using a Modified Artificial Bee Colony Algorithm', Journal of Mechanical Design, Transactions of the ASME, vol. 139, no. 7.View/Download from: UTS OPUS or Publisher's site
Copyright © 2017 by ASME. Multicell tubal structures have generated increasing interest in engineering design for their excellent energy-absorbing characteristics when crushed through severe plastic deformation. To make more efficient use of the material, topology optimization was introduced to desi gn multicell tubes under normal crushing. The design problem was formulated to maximize the energy absorption while constraining the structural mass. In this research, the presence or absence of inner walls were taken as design variables. To deal with such a highly nonlinear problem, a heuristic design methodology was proposed based on a modified artificial bee colony (ABC) algorithm, in which a constraint-driven mechanism was introduced to determine adjacent food sources for scout bees and neighborhood sources for employed and onlooker bees. The fitness function was customized according to the violation or the satisfaction of the constraints. This modified ABC algorithm was first verified by a square tube with seven design variables and then applied to four other examples with more design variables. The results demonstrated that the proposed heuristic algorithm is capable of handling the topology optimization of multicell tubes under out-of-plane crushing. They also confirmed that the optimized topological designs tend to allocate the material at the corners and around the outer walls. Moreover, the modified ABC algorithm was found to perform better than a genetic algorithm (GA) and traditional ABC in terms of best, worst, and average designs and the probability of obtaining the true optimal topological configuration.
Wu, C, Gao, Y, Fang, J, Lund, E & Li, Q 2017, 'Discrete topology optimization of ply orientation for a carbon fiber reinforced plastic (CFRP) laminate vehicle door', MATERIALS & DESIGN, vol. 128, pp. 9-19.View/Download from: UTS OPUS or Publisher's site
Pang, T, Li, Y, Kang, H, Sun, G, Fang, J & Li, Q 2017, 'On functionally-graded crashworthy shape of conical structures for multiple load cases', Journal of Mechanical Science and Technology, vol. 31, no. 6, pp. 2861-2873.View/Download from: UTS OPUS or Publisher's site
© 2017, The Korean Society of Mechanical Engineers and Springer-Verlag GmbH Germany. Many studies on energy absorbers have been focused on tapered tubes because they have significant advantages in crashworthiness and provide a desired constant load-deflection response. However, few studies have been reported on tapered tubes with nonlinearlyvariable diameters along the longitudinal direction. This paper presents thin-walled Functionally graded tapered tube (FGTT) with a diameter varying nonlinearly subject to axial (0°) and oblique (10°, 20°, 30°) impacts. To explore the advantages of FGTT, conventional Straight/Conical circular tube (SCT/CCT) with the same mass are compared; and FGTTs with a gradient exponent n > 1 are found to be preferable to others in terms of energy absorption capacity under small impact angles. Then, crashworthiness analyses of different crushing distances are conducted and it is found that under a large impact angle (e.g. 20°, 30°), FGTT with a short crushing distance (e.g. 40 mm) have a higher mean crashing force than long crushing distance (e.g. 120 mm), especially for n > 1. In addition, the effect of geometric parameters, such as the gradient exponent n and diameter range D between top (incident) and bottom (distal) diameters of FGTTs, are also studied and it is found that the FGTT with D = 40 mm and n > 1 exhibits better crashworthiness than the others under small impact angles (0°, 10°). This paper demonstrates that such FGTT structures have a certain potential to be an energy absorber.
Gao, Y., Han, J., Fang, J. & Wang, S. 2016, 'Programmed Load Spectrum for Fatigue Bench Test of a Vehicle Body', SAE International Journal of Materials and Manufacturing, vol. 9, no. 3.View/Download from: UTS OPUS or Publisher's site
Copyright © 2016 SAE International. A compiled method of the programmed load spectrum, which can simplify and accelerate the fatigue bench test of a car body, is proposed and its effectiveness is checked by the fatigue simulation. By using the multi-body dynamics model with a satisfactory accuracy, the virtual iteration is applied to cascade body loads from the wheel hubs. Based on the rain-flow counting method and statistics theory, the distributions of the body loads are analyzed, and then the programmed load spectrum is compiled and simplified. Through comparative study, the simulation results of random and programmed load spectrum are found to agree well with each other in terms of the damage distribution and fatigue life, which demonstrates the effectiveness of the presented method.
Fang, J, Gao, Y, An, X, Sun, G, Chen, J & Li, Q 2016, 'Design of transversely-graded foam and wall thickness structures for crashworthiness criteria', COMPOSITES PART B-ENGINEERING, vol. 92, pp. 338-349.View/Download from: Publisher's site
Li, E, Chen, J, Zhang, Z, Fang, J, Liu, GR & Li, Q 2016, 'Smoothed finite element method for analysis of multi-layered systems - Applications in biomaterials', COMPUTERS & STRUCTURES, vol. 168, pp. 16-29.View/Download from: UTS OPUS or Publisher's site
Qiu, N, Gao, Y, Fang, J, Feng, Z, Sun, G & Li, Q 2016, 'Theoretical prediction and optimization of multi-cell hexagonal tubes under axial crashing', THIN-WALLED STRUCTURES, vol. 102, pp. 111-121.View/Download from: UTS OPUS or Publisher's site
Sun, G, Jiang, H, Fang, J, Li, G & Li, Q 2016, 'Crashworthiness of vertex based hierarchical honeycombs in out-of-plane impact', MATERIALS & DESIGN, vol. 110, pp. 705-719.View/Download from: Publisher's site
Fang, J, Gao, Y, Sun, G, Xu, C & Li, Q 2016, 'Multiobjective sequential optimization for a vehicle door using hybrid materials tailor-welded structure', PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL ENGINEERING SCIENCE, vol. 230, no. 17, pp. 3092-3100.View/Download from: UTS OPUS or Publisher's site
Entezari, A, Fang, J, Sue, A, Zhang, Z, Swain, MV & Li, Q 2016, 'Yielding behaviors of polymeric scaffolds with implications to tissue engineering', MATERIALS LETTERS, vol. 184, pp. 108-111.View/Download from: Publisher's site
Gao, Y., Guo, Q., Fang, J., Wang, J. & Liu, W. 2015, 'Lightweight design of car body based on sequential kriging model', Qiche Gongcheng/Automotive Engineering, vol. 37, no. 4, pp. 460-465.
©, 2015, SAE-China. All right reserved.In view of the low fitting accuracy of conventional Kriging model in design space, sequential Kriging model is proposed. New sample points are added in the neighborhood of optimization solution and the sparse region of design space by using expected improvement function, and the surrogate model is constantly updated to enhance the fitting accuracy in the region of interest and the global prediction ability of the model. Through two numerical examples, the global searching characteristics of sequential Kriging model are analyzed. It can be seen from the statistical result of optimization numerical examples that the optimization accuracy and robustness of sequential Kriging model are higher than those of conventional Kriging model. Finally, sequential Kriging model is applied to a car-body lightweight design and the results of optimization with particle swarm optimization algorithm show that the accuracy of surrogate model is greatly improved and the mass of selected components is reduced by 23.35% while satisfying the constraints of crashworthiness.
Gao, Y., Zhang, Y. & Fang, J. 2015, 'Design of an aluminum bumper beam based on hybrid cellular automata', Tongji Daxue Xuebao/Journal of Tongji University, vol. 43, no. 3, pp. 456-461.View/Download from: Publisher's site
©, 2015, Science Press. All right reserved.In order to improve the crashworthiness and simultaneously achieve the lightweight goal, a design method was proposed for an aluminum bumper. A crashworthiness simulation model was established first and topology optimization was conducted based on hybrid cellular automata (HCA). The material distribution from topology optimization was used to generate H-shaped cross-section. Base on the Kriging modeling technique, size optimization was executed to acquire the optimal sectional dimension. The final result demonstrates that the proposed method is able to provide a reasonable cross-sectional shape and size of the bumper, and to improve the crashworthiness of the bumper beam and to achieve a lightweight design.
Fang, J, Gao, Y, Sun, G, Zheng, G & Li, Q 2015, 'Dynamic crashing behavior of new extrudable multi-cell tubes with a functionally graded thickness', INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES, vol. 103, pp. 63-73.View/Download from: UTS OPUS or Publisher's site
Fang, J, Gao, Y, Sun, G, Qiu, N & Li, Q 2015, 'On design of multi-cell tubes under axial and oblique impact loads', THIN-WALLED STRUCTURES, vol. 95, pp. 115-126.View/Download from: UTS OPUS or Publisher's site
Qiu, N, Gao, Y, Fang, J, Feng, Z, Sun, G & Li, Q 2015, 'Crashworthiness analysis and design of multi-cell hexagonal columns under multiple loading cases', FINITE ELEMENTS IN ANALYSIS AND DESIGN, vol. 104, pp. 89-101.View/Download from: UTS OPUS or Publisher's site
Tian, L, Gao, Y, Fang, J & An, X 2015, 'Multi-objective optimisation of hybrid S-shaped rails under oblique impact loading', International Journal of Heavy Vehicle Systems, vol. 22, no. 2, pp. 137-156.View/Download from: UTS OPUS or Publisher's site
Copyright © 2015 Inderscience Enterprises Ltd. This paper aims at optimising the crashworthiness capabilities of hybrid S-shaped rails of an automotive body under oblique impact loading. In the optimisation process, geometrical parameters, material types and the length ratios of aluminium part to the whole length are taken as design variables. Kriging metamodel techniques are performed to predict the crashworthiness criteria of specific energy absorption (SEA) and peak crushing force (PCF). In the following multi-objective optimisation design (MOD), non-dominated sorting genetic algorithm (NSGA-II) is adopted to obtain maximum SEA capacity and minimum PCF of hybrid S-shaped rails. It is found that the optimum design for a specific load angle does not necessarily guarantee the best solution when the load angle changes. More importantly, the change of weighting factor for each load angle affects the Pareto front of such MOD considerably, and thus selecting proper weights is of great importance in the crashworthiness design of hybrid S-shaped rails.
Xiao, Z, Fang, J, Sun, G & Li, Q 2015, 'Crashworthiness design for functionally graded foam-filled bumper beam', ADVANCES IN ENGINEERING SOFTWARE, vol. 85, pp. 81-95.View/Download from: UTS OPUS or Publisher's site
An, X, Gao, Y, Fang, J, Sun, G & Li, Q 2015, 'Crashworthiness design for foam-filled thin-walled structures with functionally lateral graded thickness sheets', THIN-WALLED STRUCTURES, vol. 91, pp. 63-71.View/Download from: UTS OPUS or Publisher's site
Sun, G, Fang, J, Tian, X, Li, G & Li, Q 2015, 'Discrete robust optimization algorithm based on Taguchi method for structural crashworthiness design', EXPERT SYSTEMS WITH APPLICATIONS, vol. 42, no. 9, pp. 4482-4492.View/Download from: UTS OPUS or Publisher's site
Sun, G, Tian, X, Fang, J, Xu, F, Li, G & Huang, X 2015, 'Dynamical bending analysis and optimization design for functionally graded thickness (FGT) tube', INTERNATIONAL JOURNAL OF IMPACT ENGINEERING, vol. 78, pp. 128-137.View/Download from: UTS OPUS or Publisher's site
Fang, J, Gao, Y, Sun, G, Xu, C & Li, Q 2015, 'Multiobjective robust design optimization of fatigue life for a truck cab', RELIABILITY ENGINEERING & SYSTEM SAFETY, vol. 135, pp. 1-8.View/Download from: UTS OPUS or Publisher's site
Fang, J., Gao, Y., Xu, C. & Zhang, Y. 2014, 'Multi-body dynamics model revision techniques based on surrogate model', Qiche Gongcheng/Automotive Engineering, vol. 36, no. 4.
In view of the significant effects of multi-body dynamics on the accuracy of fatigue life prediction, a multi-body dynamics model revision scheme is proposed in this paper by combining the techniques of the design of experiment, surrogate model and optimization. Firstly a multi-body dynamics model of vehicle is built with MSC. ADAMS software and the characteristics of shock absorber damping and bump stop stiffness are parameterized. Then the parameters are selected by the design of orthogonal experiment, and three types of surrogate models are compared to obtain the metamodel of higher accuracy. Finally, sequential quadric programming optimization is employed for parameter identification and the revision of dynamics model. The results show that the proposed approach can successfully obtain the non-linear dynamics characteristics of vehicle suspension and achieve the revision of multi-body dynamics model, greatly reducing development cost and shortening lead time, and the technique can be extended to other related fields.
Gao, Y., Xu, C. & Fang, J. 2014, 'Study on the programed load spectrum of the body fatigue bench test', Jixie Gongcheng Xuebao/Journal of Mechanical Engineering, vol. 50, no. 4, pp. 92-98.View/Download from: Publisher's site
A compiled method of programed load spectrum is presented, which can simplify and accelerate the body fatigue bench test. Random load spectrum of the interface points between chassis and body, which is obtained accurately by road load spectrum collected on the proving ground, is simplified to torsion load spectrum. Based on rain-flow counting method and statistical theory, the distributions of amplitude and mean are found to confirm with normal distribution and Weibull distribution respectively. Following that, the programed load spectrum is compiled and simplified. The fatigue life of the body is predicted using finite element method (FEM) and fatigue analysis theory, and the critical regions are analyzed in terms of fatigue time and driving distance. Through comparative study of the simulation result of random load spectrum and programed load spectrum, the damage distribution and fatigue life are found to agree well with each other, which demonstrate the effectiveness of the presented method. The compiled method of programed load spectrum can help other vehicles to improve the performance. © 2014 Journal of Mechanical Engineering.
Fang, J., Gao, Y., Sun, G. & Li, Q. 2014, 'Development of a novel identification platform for automotive dampers', International Journal of Vehicle Design, vol. 66, no. 3, pp. 272-296.View/Download from: Publisher's site
Copyright © 2014 Inderscience Enterprises Ltd. Traditional approaches with manual regulation of damping parameters could often be too difficult to yield correct parameters due to high nonlinearity and cross effects between different parameters involved. To tackle the problem, this paper proposes a new approach to the identification of the damping parameters for a shock absorber. In this approach, the parameter identification is modelled as an optimisation problem, in which the discrepancy between simulation and test curves is formulated as the objective function and the damping parameters to be identified are regarded as design variables. The kriging model is updated iteratively and an optimum is sought by the particle swarm optimisation (PSO) algorithm until convergence. The effectiveness and robustness of the proposed platform is validated by correlating the simulation results obtained from the identified damping parameters to the corresponding experimental results in the case of a full vehicle.
Fang, J., Gao, Y., Sun, G., Xu, C. & Li, Q. 2014, 'Fatigue optimization with combined ensembles of surrogate modeling for a truck cab', Journal of Mechanical Science and Technology, vol. 28, no. 11, pp. 4641-4649.View/Download from: Publisher's site
© 2014, The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg. In this study, we propose the ensembles of surrogates for an industrial application of fatigue optimization problem that aims to maximize a truck cab's fatigue life. After validating the numerical model, different ensembles of surrogates comprised polynomial response surface (PRS), radial basis function (RBF) and Kriging (KRG) models are established to approximate the fatigue life function. A hybrid PSO algorithm, which integrates the standard PSO with sequential quadratic programming (SQP), is implemented here to seek a quasiglobal optimum. Compared with individual surrogates, the ensembles of surrogates can attain more competent optima and yield a smaller surrogate error at the optimal point. Moreover, the hybrid PSO technique proves to search the better optima than the standard PSO in the fatigue optimization problem considered. Finally, it is found that a more accurate surrogate model may not necessarily produce a better optimum for the ensembles of surrogates, thus multiple ensembles are recommended without increasing much extra computational cost.
Fang, J., Gao, Y., Sun, G., Zhang, Y. & Li, Q. 2014, 'Crashworthiness design of foam-filled bitubal structures with uncertainty', International Journal of Non-Linear Mechanics, vol. 67, pp. 120-132.View/Download from: Publisher's site
© 2014 Elsevier Ltd. Structural optimization has been widely used to improve the crashworthiness of foam-filled thin-walled structures. However, majority of the existing optimization studies to date have not considered uncertainties for simplication. Its associated risk is that a deterministic optimization might deteriorate its optimality and/or violate design constraints when being present in uncertain environment. In this study, a multiobjective robust design optimization (MORDO) method is adopted to explore the design of foam-filled bitubal structures. To reduce the computational burden of highly-non-linear crash analysis, adaptive Kriging models are employed in the optimization process. In this strategy, sequential sampling points are generated over the design space and Kriging models are refitted in an iterative fashion. Based on the Kriging models, the multiobjective particle swarm optimization (MOPSO) algorithm is employed to perform the optimization, integrated with Monte Carlo simulation and descriptive sampling technique. The results demonstrate that the proposed method is capable of improving the robustness of Pareto solutions within the prescribed minimum requirements of reliability. Moreover, the influence of varying the emphasis on mean and standard deviation components is also analyzed, which can provide decision-makers with insightful design information.
Fang, J, Gao, Y, Sun, G, Xu, C, Zhang, Y & Li, Q 2014, 'Optimization of Spot-Welded Joints Combined Artificial Bee Colony Algorithm with Sequential Kriging Optimization', Advances in Mechanical Engineering, vol. 2014, pp. 1-10.View/Download from: UTS OPUS or Publisher's site
© 2014 Jianguang Fang et al. Generally, spot-welded joints are the weakest parts of structures leading to fatigue failure under fluctuating loads. Therefore, it is important to optimize the spot weld to improve the fatigue life. However, a classical optimization of the spot weld often directly couples finite element analysis (FEA) with optimization algorithm, which may fall into a local optimum or be expensive computationally. In this study, a metamodel-based optimization procedure is proposed to find the optimum locations of spot-welded joints for maximum fatigue life. Based on the initial training points, Kriging model is implemented to approximate the objective function regarding the design variables (i.e., locations of spot welds). To further overcome the defect of traditional Kriging model and improve the accuracy of optimum results, the sequential Kriging optimization (SKO) is utilized, where the Kriging model is updated iteratively by adding new training points to the training dataset till the global optimum is obtained. The optimization is run using artificial bee colony (ABC) algorithm and the results show that our proposed method is able to improve the performance of the spot-welded joint. More importantly, more competent optimum can be found and the optimization can be executed more efficiently, compared to the conventional methods.
Fang, J, Gao, Y, Sun, G, Zhang, Y & Li, Q 2014, 'Parametric analysis and multiobjective optimization for functionally graded foam-filled thin-wall tube under lateral impact', COMPUTATIONAL MATERIALS SCIENCE, vol. 90, pp. 265-275.View/Download from: UTS OPUS or Publisher's site
Gao, Y., Xu, C., Fang, J. & Liu, W. 2013, 'An experimental study on the stiffness of automotive closures', Qiche Gongcheng/Automotive Engineering, vol. 35, no. 12, pp. 1117-1122.
Taking the closure panels of a passenger car as an example, the contents, specifications and procedures of stiffness test for automotive closures are presented in this paper. In addition, the finite element analysis software Abaqus is used to analyze the relevant factors influencing the results of stiffness test, providing references for the structure design of automotive closures.
Fang, J., Gao, Y. & Xu, C. 2013, 'Displacement back-calculation of body fatigue loading spectrum', Tongji Daxue Xuebao/Journal of Tongji University, vol. 41, no. 6.View/Download from: Publisher's site
A procedure of the spindle displacement back-calculation to acquire body loading spectrum is presented through a case study of a light-duty bus. First, road loads in the proving ground is collected by arranging some transducers. Then, the multi-body dynamic simulation model with a satisfactory accuracy is established. Finally, based on the above two factors, virtual iteration is applied to cascade body loads from the wheel hubs. The conclusion can be drawn that the simulation signals obtained from the proposed method agree well with the experimental data, and thus the load information extracted from the body interface points can be utilized to evaluate the fatigue lifetime.
Gao, Y.K., Feng, H.X., Fang, J.G. & Zhong, D.W. 2013, 'Experimental study on identification of inertia parameters of truck cab based on mass line method', Zhendong yu Chongji/Journal of Vibration and Shock, vol. 32, no. 16, pp. 193-197.
Accurate inertia parameters of a heavy truck cab, including the mass, the position of mass center, the moment of inertia and the product of inertia, and so on are basic parameters for whole vehicle dynamic analysis. A domestic heavy truck cab was focused. The frequency response functions (FRFs) were obtained by LMS data acquisition system. The center of mass in the XY plane of the cab was obtained by the weighing method. On the other hand, the center of mass of the cab was calculated based on the mass line, extracted from the FRFs. Both results were compared and show that the error in X direction was 1.99 cm and the error in Y direction is 0.68 cm. It is concluded that the mass line method is of good measurement precision. Then the moment of inertia, the product of inertia, the principal moment of inertia and the principal axis direction were calculated successively. The reasons of errors were analyzed and discussed.
Fang, J, Gao, Y, Sun, G & Li, Q 2013, 'Multiobjective reliability-based optimization for design of a vehicledoor', FINITE ELEMENTS IN ANALYSIS AND DESIGN, vol. 67, pp. 13-21.View/Download from: UTS OPUS or Publisher's site
Fang, J., Gao, Y., Wang, J. & Wang, Y. 2012, 'Multi-objective shape optimization of body-in-white based on mesh morphing technology', Jixie Gongcheng Xuebao/Journal of Mechanical Engineering, vol. 48, no. 24, pp. 119-126.View/Download from: Publisher's site
The fierce competition within the automotive industry requires manufacturers to shorten their development time for a new body, and the CAE-based optimization techniques are arousing wide attention. Compared with traditional size optimization, shape optimization in engineering optimization has greater potential. As a result, mesh morphing technology is first introduced into shape optimization, and a metamodel-based multi-objective shape optimization methodology is presented. Mesh morphing technology is employed to define the shape variables which are then screened through sensitivity analysis. An optimal Latin hypercube sampling is utilized to generate uniformly distributed sample points for fitting the Kriging models with high accuracies. A multi-objective particle swarm algorithm is adopted to perform the optimization where the mass and bending stiffness are defined as the objective functions while maintaining other performance indicators. The conclusion can be drawn that the proposed methodology is used to perform the multi-objective optimization for body-in-white successfully, and engineers can handle the trade-off between the objectives for guiding the decision-making.
Gao, Y., Wang, J., Fang, J. & Wang, Y. 2012, 'Structural optimization of body-in-white based on bi-level programming', Jixie Gongcheng Xuebao/Journal of Mechanical Engineering, vol. 48, no. 22, pp. 98-104.View/Download from: Publisher's site
An optimization with a high-dimensional design space and multi-form variables processed within an all-in-one optimization is sometimes unsolvable. Therefore, it is decomposed into a multi-level optimization with a low dimension and variables of single form. An optimization decomposed into a bi-level problem in which the upper-level and the lower-level interdepend, interact and codetermine the responses, is a bi-level programming problem. However, due to the optima of the lower-level are searched within the decision environment of the upper-level, a bi-level programming is intrinsically hard. So iterations between the upper-level and the lower-level are performed. To enhance the body-in-white performance and achieve lightweight, both section shape and shell thickness optimization should be executed. The complex section shape parameterized by mesh morphing technology is accompanied with problems of shell penetration and poor element quality, which result in the failure of reanalysis within all-in-one optimization and in turn terminate the iteration. Therefore, the section shape optimization is applied based on response surface model. While to achieve lightweight, the design variable size of the size optimization should be increased. With the improvement of the design space dimension, sample points multiply accordingly and the fitting accuracy declines radically. So the size optimization is applied in Nastran Sol200. Considering the traits of section shape and shell thickness optimization, a bi-level programming is introduced into the structural optimization of body-in-white, so that the unsolvable optimization is settled, meanwhile the static stiffness and modal frequency are enhanced greatly and lightweight is achieved.
Wang, Y., Fang, J., Wang, J. & Tian, L. 2012, 'A research on the application of mesh morphing technology to car body retrofit design', Qiche Gongcheng/Automotive Engineering, vol. 34, no. 9, pp. 847-851.
The mesh morphing technology is applied to the retrofit design of a baseline car model in this paper. Specifically, according to the morphing scheme worked out, the geometric dimension of FE model for its body-in-white is changed to build the FE model for new car model efficiently, with its performance predicted by finite element analysis. The results indicate that with mesh morphing technology, the dependency of design on detailed CAE data and the time-consuming preparation activities for simulation can be avoided, with the lead time for car model development shortened and the development cost reduced, truly embodying the vision of 'CAE leads design'.
Gao, Y., Fang, J. & Xie, M. 2012, 'Durability analysis and evaluation of a frame-type heavy truck cab', Tongji Daxue Xuebao/Journal of Tongji University, vol. 40, no. 5, pp. 723-728.View/Download from: Publisher's site
According to loading spectrum collected in the road test, the bench test was designed. Fatigue life simulation and test of a frame-type heavy truck cab were conducted, and the results were compared with those of the benchmark. The results of simulation and test were comparable, and the design weaknesses were checked out. Finally, a new method was proposed that force decreasing rate was regarded as an indicator to evaluate cab's equivalent life.
Gao, Y, Fang, J & Xie, M 2012, 'Structural analysis and optimization for a frame-type cab of a heavy-duty truck', Applied Mechanics and Materials, vol. 182-183, pp. 1499-1503.View/Download from: UTS OPUS or Publisher's site
The structural analysis of a cab can examine its performances, and then provide a direction for structural optimization. This paper takes a frame-type cab as the research subject, its finite element model and corresponding test scheme are established, and then its torsion stiffness and modal characteristics are analyzed through both simulation and test. Appropriate variables for optimization are screened according to sensitivity analysis. Finally structural optimization for the cab is conducted, so that its torsion stiffness is improved effectively, and simultaneously the structural lightweight design is accomplished on the premise of maintaining the lower modal frequencies on the original level. © (2012) Trans Tech Publications, Switzerland.
Lu, S., An, Y., Fang, J. & Zhang, J. 2011, 'Structural design of energy-absorbing front underrun protective device for commercial vehicles', Qiche Gongcheng/Automotive Engineering, vol. 33, no. 12, pp. 1043-1046.
In view of the problem of insufficient stiffness of the front underrun protective device (FUPD) in a commercial vehicle, the plate-type bracket structure of original FUPD is redesigned by applying both topology and parameter optimization techniques with a crash buffering box beam added on. A simulation analysis is performed on the redesigned FUPD with LS-DYNA. The results show that the new FUPD not only solves the problem of inadequate stiffness, i.e. gains the function of front underrun resistance, but can also play the role of buffering and energy absorption.
Copyright © 2016 SAE International.As a potential material for lightweight vehicle, polymethyl methacrylate (PMMA) has proven to perform well in optical behavior and weather resistance. However, the application in automotive glazing has seldom been studied. This paper investigates the defrost performance of PMMA rear window using both numerical and experimental methods. The finite element analysis (FEA) results were found to be in good agreement with the experimental data. Based on the validated finite element model, we further optimized the defrost efficiency by changing the arrangement of heating lines. The results demonstrated the frost layer on the vision-related region of PMMA rear window can melt within 30 minutes, which meets the requirement of defrost efficiency.
Gao, Y, Feng, Z, Fang, J & Wang, S 2016, 'Research on the Fatigue Durability Performance of a SUV Rear Axle', SAE Technical Papers, SAE World Congress, SAE, Detroit, USA, pp. 1-8.View/Download from: UTS OPUS or Publisher's site
© Copyright 2016 SAE International.The performance of the rear axle plays an important role in the performance of vehicle, and its fatigue durability is an integral part in the vehicle development. Taking a SUV model as the research subject, a new methodology of multi-channel spindle coupled road simulator and fatigue simulation analysis for rear axle assembly was introduced in the paper, aiming to address the fatigue design and its verification for the rear axle in the development phase. Firstly, road loads in the proving ground was collected by arranging proper sensors. Secondly, physical iteration was performed on the multichannel spindle coupled road simulator by taking six component forces at the wheel hub as the target signals. Then, after the time waveform replication of the loads the durability test was conducted. Finally, the validated simulation model was successfully implemented to improve the fatigue life of the axle.
Fang, J, Xu, F, Sun, G, Li, G, Gao, Y & Li, Q 2014, 'Crashworthiness investigation for functionally graded thickness (FGT) circular column', 8th Australasian Congress on Applied Mechanics, ACAM 2014, as Part of Engineers Australia Convention 2014, Australasian Congress on Applied Mechanics, Informit, Melbourne, Australia, pp. 191-197.View/Download from: UTS OPUS
There has been continuous pursuit of new thin-walled structures in transportation and defense industries recently for more efficient usage of materials in order to achieve light weight and high energy absorption. In this paper, a functionally graded thickness (FGT) tube with a varying wall thickness along axial direction is introduced. The established finite element model of FGT circular tube is validated by performed physical experiments. Numerical analysis demonstrates that gradient exponent controlling the variation of thickness distributions and the thickness interval have significant effect on governing the percentage increase in absorbed-energy. Furthermore, the FGT circular column is found superior to the uniform thickness column in crashworthiness.
Gao, Y, Qiu, N, Fang, J & Wang, S 2014, 'A test method and simulation study of PMMA glazing on motion deviation', SAE Technical Papers, SAE 2014 World Congress & Exhibition.View/Download from: Publisher's site
For achieving vehicle light weighting, the motion deviation is calculated for substitution of PMMA glazing for inorganic glass. In this paper, a test method is proposed to measure and calculate the motion deviation of the dual-curvature glass. To simulate the dual-curvature glass, the torus surface is fitted with least square method according to the window frame data, which are measured by Coordinate Measuring Machine. By using this method, the motion deviation of PMMA glazing and inorganic glass can be calculated, which can not only validate the effectiveness of motion simulation, but also compare the performances. The results demonstrate that the performance of PMMA glazing is better than that of inorganic glass and the simulation results is validated. Copyright © 2014 SAE International.