# Design optimization methods

In this article we'll tell you about the methods and tools we use at Femto Engineering for design optimization.

Often we get customer requests for lightweight engineering, e.g. products need to be optimized for weight. But, design optimization is more than reducing weight. It’s about maximizing performance and efficiency of material application while minimizing life-cycle cost. Finite Element technology provides us with tools for structural design optimization throughout several design phases. Techniques that attempt to improve or find the best mechanical structures can be classified into three categories.

## Sizing Optimization

The first category in structural design optimization techniques is sizing optimization. Without changing the general shape of the geometry an optimum relation between weight, stiffness and the dynamic behavior is found by optimizing sheet thicknesses. In early design phases a free sizing approach helps to get best indications for sheet partitioning and in later design phases the sizing optimization can lead to optimal thicknesses for all individual sheets in the structure. An example of sizing optimization is illustrated in the image on the left. Images are courtesy of Tosca.

## Shape Optimization

The second category in structural design optimization techniques is shape optimization. This method of optimization determines the optimal shape of the structure with the given sheet thicknesses by slightly changing the surface geometry to minimize stress peaks which in turn positively influences fatigue life. An example of shape optimization is illustrated on the left.

## Topology Optimization

Topology optimization is a mathematical method that optimizes material layout within a given design space, for a given set of loads, boundary conditions and constraints with the goal of maximizing the performance of the system. Unlike sizing- and shape optimization, structures optimized through topology optimizations can attain any shape within the design space. Want to know more about topology optimization? Click the link for an in-depth read on this topic.

## Software tools

Depending on the challenge at hand we employ a variety of design optimization tools. At Femto Engineering we use  optimization modules from i.a. Simcenter 3D, Femap/NX Nastran and Altair Optistruct. We can advise you on the right tools for your challenges. Our engineers can also help optimize structures and product performance on a project basis. If you are interested in our design optimization services, get in touch!

August 7, 2017
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