Probabilistic Contact Force Model For Low Velocity Impact On Honeycomb Structure

The analysis and design of honeycomb sandwich structures involve quantification of dynamic contact force, local indentation of the structure when subjected to impact. However, the estimation of contact force is challenging as it involves wide uncertainties arising from initial conditions, geometrical and material parameters. Due to complex dynamic failure modes, the analytical solution fails to accurately predict the contact force. Therefore, the current study aims to propose a probabilistic model that can predict peak dynamic contact force when honeycomb structures are subjected to low velocity impacts. In the initial phase of this study, material and geometric parameters that could influence the response are studied in detail. The probabilistic model is developed based on these parameters and provides an estimate of peak contact force for impact energies within the defined limits. To develop the probabilistic model, we resorted to numerical simulations. It is shown that the numerical results are converging with low velocity impact experiments. Extensive finite element simulations are conducted at selective design points to generate a representative data for calibrating the probabilistic model. Once calibrated the probabilistic model circumvents any further dependency on conducting expensive FE simulations or experiments and expresses the contact force using simple explicit equation. In this paper, the emphasis is laid on the developing a probabilistic framework which could account for uncertainties involved in the estimate of structural response. The proposed model helps in designing robust honeycomb composites for application in aerospace structures.