Multi-material solutions for the light weighting of electric and internal combustion engine vehicles is the new trend to replace structural components made of metal. Automotive chassis consists of structural members such as rails, posts and rockers, which form frames that need to meet crashworthiness requirements such as frontal, side (IIHS & Pole) and roll over impacts. In the present paper, we discuss the design and optimization of metal plastic hybrid (MPH) based rocker panel solutions to meet pole impact requirements. Rocker panel structures are situated at the bottom in the lateral edges of the vehicle and extend longitudinally along the length of the vehicle, between the front and rear wheels. Electric Vehicles (EVs) having batteries below the floor along the vehicle length. Rocker panel structures are reinforced to absorb the energy during a crash protecting the battery from intrusion and shock. Metal rocker panel structures are made with multiple reinforcements (sandwich/ extruded tubular metal structures) and a sequence of assembly processes are involved to attach them onto the vehicle frame. Lower package space and energy absorption to avoid intrusion and damage to sub-structural parts during pole impact (a regulatory requirement) is the key challenge for rocker panel design. Honeycomb-based MPH rocker panel structures were designed to absorb impact energy in the available/limited package space for pole impact requirements. Material models (MAT 24 & MAT187) were developed using high strain rate data, and simulations were performed to optimize the design using LS Dyna. The MPH rocker panel developed is 40% lighter in weight with similar performance, when compared with the metal solution.
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