Topology Optimization

Topology Optimization (TO) is a mathematical process that optimizes the material layout and structure within a given three-dimensional geometric design space for certain predefined rules set by a designer. The purpose of this optimization is to maximize part performance by modeling and optimizing factors such as external forces, load conditions, boundary conditions, constraints and material properties within the design envelope.

How is Topology Optimization Made?

RO is usually performed at the final stage of the design phases, when the targeted product needs to be lighter. Therefore, there is already a basic design model for setting up the TO analysis.

• First, the designer determines the smallest allowable design space required for the product.
• Next, the material properties, boundary conditions, constraints and user external loads are defined. During this phase, exclusion areas or fixed locations are also determined.
• FEA then considers the least geometric design envelope and divides the design space into smaller areas such as applied load points, mounting locations, and constrained areas.
• TO creates a basic mesh of this smaller design space using finite element analysis. FEA (Finite Element Analysis) then evaluates the stress distribution and strain energy of the mesh to find the optimum load or stress that each element can handle.
• The TO program then digitally prints the design from various angles, evaluates its structural integrity, and detects redundant materials.
• The topology optimization software then tests each finite element for stiffness, conformity, tension, deflection against the defined requirement to find excess material.
• Finally, finite element analysis puts the pieces together to complete the pattern.

Advantages and Disadvantages of Topology Optimization

Topology Optimization Advantages

• Optimized Design – TO helps quantify optimal design. Infinite element analysis considers many factors and avoids making dangerous assumptions that could lead to incorrect elements.
• Minimum Material Use – The most notable benefit of this optimization is its ability to reduce unnecessary material and increase the hardness-to-weight ratio. The lower weight and size also results in smaller products and less energy consumption. In addition, the optimized design will reduce the raw material required and thus be sustainable for our world.
• Cost-Effective – RO designs will be more economical with an appropriate manufacturing process. Because by placing the material only in the necessary places, you minimize the use and cost of the material. It also saves you money on other factors such as less energy for packaging, handling and shipping. Many of the complex geometries resulting from this optimization will make standard manufacturing processes impractical. However, when combined with 3D printing, this complexity comes at no extra cost.
• Reducing Environmental Impact – RO design is sustainable as it generates less waste. However, if the wrong manufacturing is selected, this may not be correct. For example, TO designs are more suitable for additive manufacturing. For machining, it is vital to start the design pattern as small as possible to minimize material removal and minimize waste.
• Faster Iterative Design Process – Reduces the risk of failure by going through various modes and taking into account the stress of components.
  Faster Time to Market – As a result of a fast and easy-to-produce design optimization, you can be the first to enter the market much earlier than your competitors.

Topology Optimization Disadvantages

• Manufacturability Limitations – Topology-optimized designs contribute better to additive manufacturing than subtractive manufacturing. Because in machining you have to remove the material, so it is time consuming. Material wastage also keeps costs high.
• Higher Cost – As some of the optimized designs are only suitable for 3D printing or in some cases injection molding or die casting. However, the cost of Additive Manufacturing is still high compared to some traditional manufacturing methods.
• Power Down – As it is like any other software, output will depend heavily on user input. Therefore, minimizing weight can reduce power in some conditions.
• Lack of Understanding – Topology optimization has been around for decades but only now comes to the fore with the introduction of 3D Manufacturing. Tools are also being introduced, but it looks like we still need time to mature and nurture the industry.