Multi-objective and multi-constraint design optimization for hat-shaped composite T-joints in automobiles

Abstract This study presents a multi-objective design optimization methodology on geometry and lay-ups for carbon fiber reinforced plastics (CFRP) T-joints in automobiles to achieve car body lightweight design. The CFRP T-joint was subjected to out-of-plane bending load using experimental method, and a finite element analysis (FEA) method was developed to simulate full failure procedure in the hat-shaped composite T-joint. A multi-objective and multi-constraint design optimization problem was then formulated to find optimum geometry and lay-ups of the composite T-joint. The non-dominated sorting genetic algorithm II (NSGA-II) was introduced to search for global optimum solution, and radial basis function (RBF) approximations for the objective functions were applied to reduce the computational cost. An original method was proposed for the initialization of the optimization that significantly accelerates the search for the Pareto front. The proposed method was validated by an obtained optimum design of a composite T-joint with reduced weight and improved overall stiffness and strength behavior, and can thus provide a guidance in practical vehicle composite joint design.

[1]  P. Hamelin,et al.  Static and dynamic behavior of combined composite aluminium tube for automotive applications , 2000 .

[2]  Thomas J. Santner,et al.  The Design and Analysis of Computer Experiments , 2003, Springer Series in Statistics.

[3]  Giovanni Belingardi,et al.  Lightweight design and crash analysis of composite frontal impact energy absorbing structures , 2012 .

[4]  A. Sudjianto,et al.  An Efficient Algorithm for Constructing Optimal Design of Computer Experiments , 2005, DAC 2003.

[5]  L. Tong,et al.  Bending behavior of single hat-shaped composite T-joints under out-of-plane loading for lightweight automobile structures , 2018 .

[6]  Nan Zhang,et al.  Multi-objective optimization of crashworthiness for mini-bus body structures , 2017 .

[7]  Jasbir S. Arora,et al.  Nonlinear structural design sensivitity analysis for path dependent problems. Part 1: General theory , 1990 .

[8]  B. Martorana,et al.  Design Optimization and Implementation of Composite and Recyclable Thermoplastic Materials for Automotive Bumper , 2011 .

[9]  R. Al-Mahaidi,et al.  Impact behaviour of carbon fibre reinforced polymer (CFRP) strengthened square hollow steel tubes: A numerical simulation , 2018, Thin-Walled Structures.

[10]  Influence of geometry modifications of vehicle body joints on their structural behaviour , 2009 .

[11]  H. Elbanna,et al.  Determination of aerodynamic sensitivity coefficients in the transonic and supersonic regimes , 1989 .

[12]  Giovanni Belingardi,et al.  Design of a composite engine support sub-frame to achieve lightweight vehicles , 2014 .

[13]  N. Silvestre,et al.  Comparative study between XFEM and Hashin damage criterion applied to failure of composites , 2017 .

[14]  Z. Hashin.  Failure Criteria for Unidirectional Fiber Composites , 1980 .

[15]  J. Mutua.  Use of magnesium alloys in optimizing the weight of automobile: Current trends and opportunities , 2011 .

[16]  Guangyong Sun,et al.  Energy absorption mechanics for variable thickness thin-walled structures , 2017 .

[17]  Zhao Liu,et al.  Lightweight design of automotive composite bumper system using modified particle swarm optimizer , 2016 .

[18]  T. Kubiak,et al.  Load-carrying capacity of thin-walled composite beams subjected to pure bending , 2017 .

[19]  Michael R. Bambach,et al.  Fibre composite strengthening of thin steel passenger vehicle roof structures , 2014 .

[20]  Qiang Liu,et al.  Lightweight design of carbon twill weave fabric composite body structure for electric vehicle , 2013 .

[21]  G. Belingardi,et al.  Geometrical optimization of bumper beam profile made of pultruded composite by numerical simulation , 2013 .

[22]  Ping Zhu,et al.  Metamodel-based lightweight design of B-pillar with TWB structure via support vector regression , 2010 .

[23]  G. Belingardi,et al.  An experimental and finite element study of the transverse bending behaviour of CFRP composite T-joints in vehicle structures , 2015 .

[24]  Hiroyuki Hamada,et al.  Application of FRP in a vehicle for Student Formula SAE Competition of Japan , 2012 .

[25]  Zhong-qin Lin,et al.  Experimental study of glass-fiber mat thermoplastic material impact properties and lightweight automobile body analysis , 2004 .

[26]  Jaroslaw Sobieszczanski-Sobieski,et al.  Sensitivity analysis and multidisciplinary optimization for aircraft design - Recent advances and results , 1990 .

[27]  Giovanni Belingardi,et al.  Implementation of Composite material car body structural joint ad investigation of its characteristics with geometry modifications , 2010 .