Using shapeAI to find mirrored parts
Altair EmployeeHave you seen the new “AI/ML” group on the “Assembly” ribbon in HyperMesh? These tools are powered by shapeAI, a technology which allows us to interpret geometry and mesh into a format on which we can use machine learning.
Match lets you find or group components by similarity. In this blog you can see an example of how this tool can be used to find different instances of aerospace components such as wing ribs within a larger model.
Classify allows you to train an ML model to identify parts based on their geometry. This could be used to automate the meshing process of different recognized components, as described in this blog.
Using shapeAI to understand the geometry DNA of a part opens up a huge number of opportunities for automation and improvement of workflows. One such opportunity is to simplify the process of harmonizing design variable or part properties about a mirror plane. Often designs are nearly symmetric about a mid-plane, e.g., automotive and aerospace structures.
Lets try to create a prototype process for recognizing and linking parts which have been reflected about a mirror plane using only the Center of Gravity (CoG) and shapeAI. This prototype will use the following algorithm:
- Extract CoG and the shapeAI description of our parts using HyperMesh.
- Find the parts with the closest CoGs to the mirrored CoG of the part we are looking to match.
- Of the parts with a close mirrored CoG select the part with the most similar shapeAI description.
- If the closest shapeAI description is within a tolerance mark it as a mirrored part.
Lets see if the algorithm works using the public domain NHTSA Honda Accord model:
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In this test we have identified 220 mirrored parts, we could now use automation to assign linked design variables or consistent properties such as thickness or material. There are some parts such as the doors, some sections of the floor and suspensions which we would expect to also be linked, interrogation of the model shows that these subsystems are modeled within the same part. For example, the left and the right doors are stored within the same part, so do not need linking.
This feature will be appearing in future versions of Design Explorer to help automatically assign design variables to mirrored parts!
Part linking about the mid-plane is also available in the MDO (Multi-Disciplinary Optimization) Director, which you can learn more about here, but it uses a different method to shapeAI. The MDO Director allows you to link parts not only about the mid-plane but also between models, to help streamline the process of performing Multi-Disciplinary Optimizations with different solvers.
Can you think of any applications where understanding the geometry DNA of your parts can improve your process? Let us know in the comments!