Freeform optimization (or topology optimization) is a mathematical approach used in finite element analysis to determine the optimum material layout for a given design space which takes into any number of design constraints. By defining a design space that the engineer has to work in and applying boundary conditions such as predefined loads and fixture positions, topology optimization can suggest the ideal layout of material to meet defined performance targets.
It is important to note that design proposals from a freeform optimization study will present an optimal layout of material distribution which may be at odds with the manufacturing processes employed. As such there is still a need for the engineer to interpret the output from the study into a final manufacturable model that can be tested further. However, some new advances in manufacturing techniques such as additive layer manufacturing or 3D printing, has the potential for parts to closer resemble the freeform results.
Shape optimization is different from freeform (topology) optimization in that it is used once the component’s topology has already been defined. Topology optimization is used to generate material layout concepts whereas shape optimization refines and improves the topology within the concept.
Use in Industry
Freeform optimisztion is commonly used in industry as a method to reduce the material and overall weight of a component or system as it is capable of giving an engineer guidance on the minimum amount of material required to meet performance characteristics. The applications of the technology within industry are extremely varied but a few examples are presented below.
- Airbus A380 Wing Ribs
Using Altair’s OptiStruct technology, Airbus and Altair ProductDesign were able to reduce the weight of the A380’s droop nose wing ribs by 500kg per aircraft. This was achieved by defining the design space available within the wing, applying expected loads, applying freeform optimization and interpreting the result to form a new material layout. More on this project
- Tallent Automotive Chassis Development
Tallent Chassis used a combination of freeform and other optimization techniques to develop lightweight chassis structures for their automotive OEM clients. Using their own ‘eDICT’ system, Tallent Automotive successfully reduced the mass of various chassis components by as much as 25%. More on this project
- Shanghai Automotive Vehicle Development
By integrating optimization techniques into the vehicle development process at Shanghai Automotive (SAIC), it was possible to create a performance optimized design for the Roewe 550 in an aggressive timescale. More on this project
Simulation Driven Design
As the power and sophistication of simulation technology has improved, it has opened up the potential for design optimization to be applied earlier in the development process. This has created a new process for product development which Altair refer to as ‘Simulation Driven Design’.
What is it?
In the traditional design process, computer aided design (CAD) and computer aided engineering (CAE) tools are used sequentially. The designer creates the geometry in CAD and verifies it using CAE.
With the simulation driven design approach, CAD and CAE are deployed in parallel. CAE, using intelligent technology, automatically determines the optimum geometric configuration, allowing engineers to reach the best performing design, faster.
The simulation driven design approach utilizes freeform and other optimization methods to generate more mature design solutions much earlier than in a traditional development process. This allows engineers to create products which are optimized for mass and weight targets at a stage when the cost of change is at its lowest and the potential impact at its highest. More about simulation driven design.
Technical Paper - Airbus - Application of Topology Sizing & Shape Optimization Methods
Technical Paper - Bombardier Transportation - Fast Tracking Rail Vehicle Design
Technical Paper - BAE Systems – Simulation Driven Structural Design in Ship Building
Technical Paper - Tallent Automotive - Evolutionary Design in Chassis Technology
Technical Paper - Shanghai Automotive – Application of Process Automation & Optimization
Technical Paper - Weight Optimization of Turbine Blades
Technical Paper - Progress in Topology Optimization with Manufacturing Constraints
Presentation - Mazda – Skyactive Technology for Lightweight Vehicles