Concept optimization is a method of using design optimization processes to automatically define concept geometry for a structure based on design space, expected loading and other boundary conditions. It is used at the very early stages of the design process, before CAD, and allows the optimization technology to suggest an ideal material layout which is then interpreted into a manufacturable form by the engineer. Concept optimization is used to develop minimum mass structures and is a literal example of simulation driven design.
The Concept Design Process
Robust Structural Concepts for Load Carrying Structures
A concept optimization process starts with freeform optimization. The initial surfaces from styling teams are brought into OptiStruct and the areas of designable and non-designable space are defined by the engineer. Predefined loads (fatigue, crash, bending etc) are applied to the product to ensure the resulting structure can meet performance targets.
The second step is shape and size optimization. The layout for the supporting structure is studied further to create optimum beam sections. The beam model is subject to further loading with the results used to suggest the ideal size, shape and thickness of the beam structure while taking manufacturing constraints into account.
Translation into real-life Cross Sections & Generation of CAD
In the final stage, the simplified but dimensioned structures are transferred into real-life manufacturable sections. Since cross section properties are now known, OEM specific cross section libraries can be used and morphed to map the simplified sections. A fully optimized concept structure can be delivered back to the CAD and styling teams, well ahead of the standard product development process.
Freeform Optimization Generating Structural Concepts
By allowing the optimization technology to help to define the structural layout at this early leads to a more mature design earlier in the development process. This can reduce the length of the development program as a whole while reducing cost.
- Rapid prediction of structural targets (e.g. crash, NVH and durability)
- Early understanding of mass versus performance trade-offs
- Mature deliverables at the end of the concept phase
- Reduced program risk, development time and cost or have longer quality maturation loops
- Reduced requirement for additional structural engineering (expensive reinforcements, material upgrades)
Technical Paper - Coventry University – Generation of Optimised Hybrid Electric Vehicles