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Virtual proving ground (VPG) simulations have been popular with passenger vehicles. VPG uses LS-DYNA based non-linear contact Finite Element analysis (FEA) to estimate fully analytical road loads and to predict structural components durability with PG road surfaces and tire represented as Finite elements. Heavy vehicle industry has not used these tools extensively in the past due to the complexity of heavy vehicle systems and especially due to the higher number of tires in the vehicle compared to the passenger car. The higher number tires in the heavy vehicle requires more computational analysis duration compared to the passenger car. However due to the recent advancements in computer hardware, virtual proving ground simulations can be used for heavy vehicles. In this study we have used virtual proving ground based simulation studies to predict the durability performance of a trailer suspension frame.

The concept of a new finite element analysis methodology to solve vehicle system NVH problems is proposed. The approach is non-conventional in the sense that, instead of NASTRAN type implicit finite element code, the explicit nonlinear dynamic code LS-DYNA is used to conduct the time domain analysis and the FFT is then used to conduct the frequency domain analysis. The advantages of this new approach include the ability to consider material and structural nonlinearity, damping and contact interface between parts, as well as the potential of expand the frequency envelop up above 200 Hz. The main disadvantage of this method is the computing CPU time required which will become less and less important as computer speed becomes faster and faster at an increased pace. Examples of normal modes for rectangular plate, tire/wheel system, and chassis subframe are presented to illustrate the method and comparisons with results from other methods are also given whenever possible.

Computer Aided Engineering (CAE), together with CAD (Computer Aided Design) and CAM (Computer Aided Manufacturing), is an effective tool to shorten the product development cycle, to decrease the cost, and to improve the product quality of full vehicle development programs. Faster computers, cost effective hardware, and advanced software technology have accelerated CAE technology to the point that a new approach to simulating proving ground test conditions has been developed and implemented for full vehicle development programs. This paper discusses this new and integrated approach, called Virtual Proving Ground (VPG), and includes studies of Road Load Generation, Durability, Vehicle Crashworthiness, Occupant Safety, and Noise/Vibration/Harshness (NHV).