Lesson 7: Introduction to OpenCascade and CAD modelling kernels | What is OpenCascade

[@QuaoarWorkshop]

List of lessons (done and planned): analysissitus.org/forum/index.php?threads%2Flist-of-lessons.3%2F

[@blu3_enjoy]

Thank you for opening the door to this topic for me

[@avijay70s]

Thank you for this wonderful workshop

[@nsyi]

Great work thank you for your time and effort

[@freemanlai1038]

Thank you for your lesson, it helped a lot:)

[@Vivavatnik]

Спасибо, многое прояснилось!

[@loukitmyname]

Isn't Facetting very popular even in CAE? Because I don't see Boundary Representation to be easy to work with in case of FEA.

[@QuaoarWorkshop]

Maybe I failed to deliver the message clear enough in this video. What I meant here is the central role of B-rep in the entirety of CAx (CAD/CAE/CAM) world. In FEA, you anyway start from a precise CAD model to generate meshes suitable for simulation. Here, B-rep serves as a "master model" from which one can derive an analysis-ready model after some preparation. Just as a side note: there are methods that do not even require meshes (e.g., U-splines) but that's terra incognita to me :)

[@AB-bp9fi]

What is the best file format to use with open cascade for exchange data (surfaces and curves) with cad systems (NX)? IGES?

[@QuaoarWorkshop]

I'd prefer STEP unless getting a good reason to fall back to IGES.

[@sundarapandim1104]

may i know how much minimum cost of Parasolid CAD Kernel cost for 2d and 3d drawing rendering applicatiuon.

[@QuaoarWorkshop]

It's worth asking Parasolid's representatives on this matter.

[@Ronak289296]

Thanks for the video, I have a fundamental questions, What are differences between geometry kernel and a Cad SDK?

[@QuaoarWorkshop]

The answer would depend on what do you actually mean by CAD SDK. In my understanding, a CAD SDK is an API provided by a certain CAD system, like SolidWorks or Catia. In this sense, such an SDK allows you to run functions of a CAD system, including features that are not readily available in a geometric kernel. In the example with SW, the geometric kernel would be Parasolid and CAD SDK is SolidWorks itself. For parametric modeling systems, such a CAD SDK would allow you to work with a feature tree, for example. And "feature tree" is something not available in the kernel. A kernel is only supposed to equip you with all the computational geometry you'd need in a CAD package. Does this answer your question?

[@Ronak289296]

@@QuaoarWorkshop by SDK I meant solutions provided by cadsofttools.com/products/how-to-choose-dwg-sdk/

[@QuaoarWorkshop]

@@Ronak289296 I do not have any experience with those tools, so to answer for sure you'd have to try them out. For general-purpose CAD programming, you need to have a computational geometry core. Like you read your DWG/STEP/etc. data in memory to some data structure, and what can you do later on? Will you be able to run things like Boolean operations, compute mass-inertia props, evaluate curves and surface, check overlapping, generate meshes, etc. All this can be very domain-specific, while OpenCascade is a general-purpose modeler answering the common need to represent shapes and work with them on a PC. I guess this SDK can serve as a data connector to read formats like DWG/DXF, but I'm not sure they interface with OpenCascade.