Introduction: Week 5: Fusion 360 Generative Design and Topology Optimization

This week we are exploring some features in Fusion 360 including generative design and topology optimization.

Step 1: Define the Problem

The problem suggested is to make a chair. However, I have a problem with my lamp and I want to design something for it.

My lamp is a 'thin' and 'tall' structure that does not have a well-made flat bottom surface. Therefore, it is not stable when it stands. So I want to design some holding structure to stabilize it.

Step 2: Generative Design

The generative design model generates components based on specified 'rules'.

The starting bodies are usually some 'disconnected' geometries, and the model generates links in between those geometries.

After some trials, I found the designs generated are most concerned with the constraints on 'preserved bodies' and 'obstacles'. It is less intuitive comparing to direct design where you need to figure out what designs you want to keep for desired structures. Also, it is important to expect the outcomes in advance when making those 'bodies'. One method I found useful to 'expect' the outcomes of the simulation is to look at the generated 'thumbnail images' in the first several iterations. You can get an overview idea of what is going to be generated without finishing the simulation process. It generates most materials to connect with the preserved geometries and then do topology optimization on that.

Step 3: Topology Optimization

Another approach to generate optimized design is to use the shape optimization in the 'simulation' mode. In this approach, you need to specify a full mass model and the algorithm keeps reducing the materials used to render an optimized structure that satisfies all constraints. I found this approach is less controllable in terms of patterns and shapes you want to generate. As it is taking out of the materials in the process, there are a lot of rough surfaces generated. But I think it would be useful for optimization on a well-defined shape.

Step 4: 3D Printing

I tried first 3D print the optimized one with minimum materials. However, the outcome is not idea whether with or without support materials. So I chose another one in the middle of the iteration with more materials and the print was good enough that I can use it. There are some glitches on the bottom side due to the hanging structure in the design.