Dr. Akbar Farahani, VP of Global Engineering, ETA
The design of automotive body structures is driven by many competing criteria such as lower cost, weight reduction (CO2 reduction, Electric and Battery Electric Vehicle), enhanced multi-disciplinary performance and manufacturability. In addition, the introduction of new manufacturing processes and materials (e.g., AHSS, aluminum, composite) significantly increases the available design space for an automotive system.
In order to explore this large design space more effectively, while trying to reduce design cycle times, engineers at ETA use an automated design optimization driven process (Accelerated Concept to Product (ACP) Process). The process can greatly decrease the time required to identify a set of feasible, or even optimal, designs prior to building and testing the first prototype. The process is based on a systematic approach of assumption and correction philosophy.
Moreover, these tools can also compensate for the limitations of human intuition and provide design engineers with the freedom and power to seek creative solutions that are not obvious to even the most experienced engineer. ACP is driven by ACP-Concept (material and load path optimization) and ACP-3G (Geometry, Grade and Gauge optimization).
Multi-Physics, Multi-Material and Optimization Software Requirements
ACP requires finite element multi-physics solvers with multi-material capabilities (metal and composites) with non-linear capabilities. ACP acts as a data management gateway interacting with solvers, such as MSC Nastran. Today’s simulations require much more accurate material modeling, so ACP uses accurate material model representations of multi-material options for accuracy of the structural design (DIGIMAT) for plastic).
Optimization software can be used to improve any engineering system, including structural, thermal, fluid, electrical, etc. even exploring multi-material options for multi-disciplinary scenarios. ACP-Concept and ACP-3G require this type of optimization software to allow designers to automatically and concurrently explore hundreds of design parameters and their relationships in the product development and design process. Engineers can then intelligently seek optimal values for parameters that affect performance and cost. The software must have non-linear capability enabling interaction with non-linear software (MSC Topology Optimization, GENESIS, LS-OPT, ModeFrontier, etc.). ACP-Concept and ACP-3G uses the optimization code to search for designs that simultaneously satisfy the objectives and targets for crashworthiness, manufacturability, mass, cost, stiffness, durability, noise and vibration, robustness and reliability (MSC Nastran, MSC Fatigue).
Parameterization and CAE and Design integration (CAD/FEM)
ACP provides tools that create practical designs for manufacturing by creating CAE models, manipulating, analyzing, and then optimizing them to create the most efficient design. Beta CAE’s ANSA provides detailed parameterization capabilities, morphing and optimization setup, and then META is used for Post-Processing. ACP tools using ANSA allow load setting, create geometry based on topology results, load path mapping, low fidelity generation, model changes in the design’s geometry based on optimization recommendations, product system decupling for detail design optimization and manufacturing process optimization.
The ACP Process can be used at a variety of levels, ranging from multidisciplinary optimization for a parameter-specific product improvement (cost, mass or performance), to complete product development. The process allows engineers to setup loading, design variables, geometry based on topology, 3G design evaluation and target setting, as well as interfacing with most commercial solver and optimization tools, specifically MSC Products.
The ACP optimization design process achieves maximum efficacy when it is empowered to select the most advanced materials, leading to the creation of the most efficient product that is balanced between all variable conflicts.