As an open source project, for 20 years OCCT provides free access to breakthrough 3D technology to thousands of users ranging from independent enthusiasts to large businesses.
Here are some examples of groundbreaking projects using OCCT
SALOME is an open-source software that provides a generic Pre- and Post-Processing platform for numerical simulation. It can be used as a standalone application for generation of the CAD model, its preparation for the numerical calculations and post-processing of the calculation results or as a platform for integration of the external third-party numerical codes to produce a new application for the full life-cycle management of CAD models.
Visit the official website: www.salome-platform.org
KiCad is an open source software suite for Electronic Design Automation (EDA). The programs handle Schematic Capture, and PCB Layout with Gerber output.
Visit the official website: kicad-pcb.org
CAD Assistant is a viewer and converter for 3D CAD and mesh files, free for both personal and commercial use.
Visit the official website: www.opencascade.com/content/cad-assistant
FreeCAD is a multi-use parametric 3D modeler or CAD system, which development is entirely based on the principles of the Open Source Code (LGPL License). FreeCAD directly targets development in mechanical engineering and object design. It is also suitable for a wider range of engineering applications such as architecture, endpoint analysis, 3D printing and others.
Visit the official website: www.freecadweb.org
Gmsh is an open source 3D finite element mesh generator with a built-in CAD engine and post-processor. Its design goal is to provide a fast, light and user-friendly meshing tool with parametric input and advanced visualization capabilities.
Visit the official website: gmsh.info