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Stringent emission norms by government and higher fuel economy targets have urged automotive companies to look beyond conventional methods of optimization to achieve an optimal design with minimum mass, which also meets the desired level of performance targets at the system as well as at vehicle level. In conventional optimization method, experts from each domain work independently to improve the performance based on their domain knowledge which may not lead to optimum design considering the performance parameters of all domain. It is time consuming and tedious process as it is an iterative method. Also, it fails to highlight the conflicting design solutions. With an increase in computational power, automotive companies are now adopting Multi-Disciplinary Optimization (MDO) approach which is capable of handling heterogeneous domains in parallel. It facilitates to understand the limitations of performances of all domains to achieve good balance between them.

A competitive market and shrinking product development cycle have forced automotive companies to move from conventional testing methods to virtual simulation techniques. Virtual durability simulation of any component requires determination of loads acting on the structure when tested on the proving ground. In conventional method wheel force transducers are used to extract loads at wheel center. Extracted wheel center forces are used to derive component loads through multi-body simulation. Another conventional approach is to use force transducers mounted directly on the component joineries where load needs to be extracted. Both the methods are costly and time-consuming. Sometimes it is not feasible to place a load cell in the system to measure hard point loads because of its complexities. In that case, it would be advantageous to use structure itself as a load transducer by strain gauging the component and use those strain values to extract hard point loads in virtual simulation.

Automotive Suspension is one of the critical system in load transfer from road to Chassis or BIW. Using flex bodies in Multi body simulations helps to extract dynamic strain variation. This paper highlights how the MBD and FE integration helped for accurate strain prediction on suspension components. Overall method was validated through testing. Good strain correlation was observed in dynamic strains of constant amplitude in different loading conditions. Combination of different direction loading was also tested and correlated. Method developed can be used in the initial phase of the vehicle development program for suspension strength evaluation. Suspension is one of the important system in vehicle which is subjected to very high loading in all the directions. To predict the dynamic stresses coming on the suspension system due to transient loads, faster and accurate method is required. To accelerate the suspension design process it become necessary to get good accuracy in the results.

Utility or Off-road vehicles are characterized with their higher ground clearances. Higher ground clearance of vehicle requires the vehicle to have footsteps for easy entry and exit of passengers from the vehicle. A typical foot step construction consists of structural steel brackets with an Aluminum or plastic top panel. Conventional steel construction is heavier to meet weight bearing capacity and durability requirements. Our objective of this work is to explore lightweight materials which can meet these performance requirements with a lighter construction. We chose to study the continuous glass fiber reinforced plastic as an alternative to the metal construction.

Body in White (BIW) is one of the major mass contributors in a full vehicle. Bending stiffness, torsional stiffness, durability, crashworthiness and modal characteristics are the basic performance parameters for which BIW is designed. Usually, to meet these parameters, a great deal of weight is added to BIW. Sensitivity analysis helps to identify the critical panels contributing to the performance while BIW optimization helps to reduce the overall mass of the BIW, without compromising on the basic performances. This paper highlights the optimization study carried out on the BIW of a Sports Utility Vehicle (SUV) for mass reduction. This optimization was carried out considering all the basic performance parameters. In the initial phase of BIW development, optimization helps to ensure minimum BIW weight rather than carrying out mass reduction post vehicle launch.

In today’s cost-competitive automotive market, use of finite element simulations and optimization tools has become crucial to deliver durable and reliable products. Simulation driven design is the key to reduce number of physical prototypes, design iterations, cost and time to market. However, simulation driven design optimization tools have struggled to find global acceptance and are typically underutilized in many applications; especially in situations where the algorithms have to compete with existing know-how decision making processes. In this study, systematic multi-phase approach for optimization driven design is presented. Approach includes three optimization phases. In first phase, topology optimization is performed on concept BIW design volume to identify critical load paths. Architectural inputs from topology are used to design base CAD.

In today’s cost competitive environment, automotive companies are moving towards lightweight materials for reducing carbon footprint, increasing fuel economy and cost benefits. Fiber reinforced plastics (FRP) is one of the most attractive option considering its high strength to weight ratio. The advantage of continuous FRP composites is tailorability according to different performance requirements. This paper will focus on finite element analysis and optimization of automotive hood structure made up of continuous carbon fiber reinforced composite with epoxy resin based matrix. Composite hood structure is analyzed using detailed orthotropic composite laminate models and an appropriate composite material failure theory. Strength of FRPs is maneuvered by orientations of the fiber plies. Considering this, stack-up sequence optimization is performed considering bending, torsional stiffness and fundamental modes in dynamic analysis.