Tim Webb looks at an example advanced simulation technology being used to test automotive crashworthiness.
Physically accurate modeling of material damage and failure is extremely important for structural crashworthiness. Component and material failure can substantially alter the load paths and response of the vehicle in a crash event. Collaboration between Abaqus and BMW engineers have led to development of a number of new capabilities in Abaqus for accurately representing progressive damage and potential failure that can occur during a crash event in sheet metal, spot welds, rivets, and structural adhesives.
During a formal project to investigate using Abaqus for complete crashworthiness simulation, BMW selected the current 5 Series sedan as the basis for testing the structural crashworthiness. The engineering teams cataloged the existing full vehicle BMW 5 Series model and detailed simulation models of the components, subsystems, and systems were created. Each model type had to be run successfully before progressing to the next level. For example, body-in-white (BIW) impact against a rigid barrier had to run successfully before moving on to trimmed BIW against a rigid barrier. This systematic progression led to successful milestones, including frontal impact of a BMW 5 Series full vehicle model against a rigid barrier and accurately simulating frontal and side impact full vehicle load cases.
Following the success of the initial developments, BMW began a pilot production project to use the Abaqus for crashworthiness simulation for all new vehicles under development. Production usage introduced the challenge of making sure Abaqus would interface well with existing BMW simulation infrastructure, including being able to integrate with their standard pre- and post-processing software, include finite-element-based crash dummy models and take into account supplier subsystems such as airbags.
By early 2006, BMW reported it had performed over 1500 simulation runs for all relevant load cases and Abaqus was demonstrating the accuracy, robustness, reliability, and openness required for production use. Today, Abaqus and BMW engineers continue to work together to advance Abaqus crashworthiness capabilities and to widen deployment of the software for other BMW vehicle programmes to meet regulatory, market, and business demands..
Tim Webb is with Abaqus Inc is based in Providence, RI, USA. www.abaqus.com"