Converting STL to 3D CAD in Ansys Discovery using SubD

Hi everyone, this is MingYao from OZEN Engineering. In this video, I wanted to show how to convert STL files into 3D CAD. I found a really cool website on NIH that gives you a variety of STLs, publicly available for body geometries to download.

We're developing products for prosthetics or implantable devices. We have femurs, all kinds of organs, and other things you can download. The challenge is always how to turn this into a CAD model, do analysis, integrate 3D mechanical CAD with these STL components.

They're all very high-quality, good scans. I'll show you some easy ways to convert that into actual CAD geometry. Let's try this fourth lumbar. So, we have a geometry here, and it's an STL top, so lots of triangles. Historically, the capability to convert this into CAD to solid has a few options.

I can right-click and convert this into a solid, but it will be a massive CAD model because there are so many. It's a lot of work. I'm trying to recreate this model, which is very difficult. It would take a lot of time for me to carefully craft something like this.

In the latest release of Discovery, we have something called Sub-D modeling, subdivision modeling. If you don't have that option on your toolbar, go to customize settings, customize ribbons, and turn on the Sub-D branch. This gives me the ability to see subdivision options here.

To convert this model from a facet geometry into a Sub-D model with one millimeter of tolerance. I hit okay here. I'm just going to try to convert this large STL into a CAD model for me. It's much easier to handle. So, we have a Sub-D model here.

We also have the STL here, so I can choose to see the STL. You can see the way that the Sub-D model takes on the shape of the STL without capturing all of the details. With subdivision, we can choose to move things around. So, for example, if I feel like this one is a little bit too big.

I can grab it and I can just pull on it. I can grab any of these areas, maybe I want to select a few of these and say, hey, I feel like these areas should bulge out a little bit more. I can just do that.

Or I can subdivide the geometry as we see here and get even more refined areas, maybe capture some of these protrusions. So now, we have a Sub-D model here that's obviously much easier to handle. We can convert this model, we can do a convert, this one from Sub-D to solid.

So, let's go ahead and do that. We also keep the original models now. I have three models. I have the fastest geometry, the Sub-D, as well as the solid model. OK. Convert to solid model, Sub-D, and faster the geometry. So, if I wanted to draw something here, let's say we sketch on this.

I draw a cylinder on this surface and pull on it. And we can, for example, compare the two. I can just do the same thing. I can, for example, combine. So, operate this just as if we're doing a regular CAD model. OK. Combine it together. Now, I have a single geometry that looks like this.

And I can make changes to it by adding fillets. What's really interesting about the Sub-D model is that it's very easy to do. You can do it in a few different ways. You can do it in a few different ways. You can do it in a few different ways. You can do it in a few different ways.

You can do it in a few different ways. You can do it in a few different ways. You can do it in a few different ways. You can do it in a few different ways. You can do it in a few different ways.

If I'm doing a regular CAD model, you can see it's very difficult to make organic shapes like I have here with the bone type of geometry. But with the Sub-D model, I easily was able to modify the geometry. So, here I'm trying to pull on this. It's trying to maintain continuity.

And it basically is not allowing me to adjust the geometry. But if I hide my solid models and turn on my Sub-D model, it's going to be very easy to modify the geometry. So, I'm going to do that. So, I can grab a single point here and move it around. So, I can bring it up.

I can rotate it and say, pull it in this direction. I can grab any surface and I can pull normal to it or pull into it. Make it concave or convex. Or pinching the part here. Or pinching the part here. Or pinching the part here.

I can select specific points here and maybe I'll say, hey, let's make this a little bit more protruding like that. So, Sub-D gives you the ability to really create organic shapes, which is ideally suited for organic geometry like body models here, human body scans.

We're able to convert easily and very quickly a 3D scan model into a Sub-D model and that can be at the end converted into solid models, which can be operated on by standard CAD operations.

So, a very short example of how we can take an STL from, for example, the NIH database, convert it into a CAD model for analysis or integration with existing mechanical CAD and also modify it as needed in the Sub-D form to create the most accurate analysis.

So, if I want to see a good scan of the model in the 3D model, I can just go to the large array and select the kineticis model and then click on this model. So, if I want to see a good scan of the model in the 3D model, I can just go to the large array and then click on this model.

Create more organic shapes. Hopefully, this was interesting for you. There's a new capability that seems really helpful for many of our customers. If you're interested in videos like this, please like this video and subscribe to our YouTube channel.

If you have any questions, please feel free to reach out to OzenInc.com. Thanks, have a nice day. Subtitles by the Amara.org community