An Approach Towards the Input Load Calculation for Determining Vehicle Body Durability Performance in Proving Ground.

In the competitive automotive market, the vehicle must be designed and validated quickly without compromising the build quality. Vehicle durability is one of the key aspects in which vehicle structure quality can be analysed. The vehicle's durability is tested either by the accelerated testing equipment e.g. multi-axial simulators in the test labs or "Proving ground" testing which depicts the same quantum of damage which occurs in actual road running conditions. In both these cases, the actual prototype vehicle must be built and evaluated which increases the cost and actual product development time. Proving Ground simulation is an alternative way to the actual endurance test running for durability evaluation. The two major steps for Proving Ground simulation are to build and extract the loads at the suspension-body attachment points and to calculate the fatigue life of the body using these loads. In this paper, two approaches of load extraction at the attachment points have been described using ADAMS rigid & flex models. The first approach is the calculation of the force as an input and the second approach is the calculation of the acceleration as an input. In both approaches, the acceleration vs time as an output is calculated on the trim Body model and compared with the actual measurement data. A detailed study is carried out in this paper to find the applicability of these approaches in terms of correlation accuracy, complexity of ADAMS model building, parameters affecting the response calculations, analysis time & scalability.