CAD Kernel Technology & Reverse Engineering Solutions for 3D Design | PSH Design - PSD Design

CAD Kernel , The Core of 3D CAD Design and Professional Reverse Engineering by PSH Design

Introduce :

A CAD Kernel is the core component (also known as the “engine”) of computer-aided design (CAD) software. It serves as the foundational software responsible for processing, creating, displaying, and manipulating 2D and 3D geometric entities within the CAD environment. All operations such as drawing, solid modeling, trimming, editing, and geometric analysis are performed through the CAD Kernel.

Some prominent kernels in the CAD industry include Parasolid (used in SolidWorks, NX, etc.), ACIS (for AutoCAD, BricsCAD, etc.), Granite (Creo), and OpenCASCADE (open-source). These kernels determine the modeling capabilities, accuracy, processing speed, and interoperability of geometry data among different software. Each CAD program typically integrates a specific kernel, and data exchange or CAD file conversion largely depends on the kernel the software uses. Therefore, the CAD Kernel is the “heart” of every modern 3D CAD software — much like an engine powers a car, it drives every geometric function of the software.

The Three “Hearts” of the 3D CAD World: ACIS, Parasolid, and CGM

In 3D design software, the three leading geometric kernels — ACIS, Parasolid, and CGM — form the foundation for hundreds of engineering programs worldwide. Each kernel has its own historical background and unique strengths, helping shape the modern design industry.

ACIS : The Pioneer with Wide Influence

• Origin: 1989, developed by experts from Cambridge at Three-Space Ltd.
• Development & Ownership: Acquired by Spatial, now part of Dassault Systèmes, in 2000.
• Highlights: Object-oriented C++ architecture; one of the first widely licensed commercial kernels; has many forks like Autodesk ShapeManager (basis for Inventor, AutoCAD 3D) and PTC Creo Elements/Direct variants.
• Applications: Besides traditional CAD, ACIS is widely used in architecture, manufacturing, metrology, simulation due to its flexible customization.
• Key Users: Autodesk, PTC, Hexagon, Bricsys, IMSI, Siemens Mentor Graphics (EDA), LK, Mitutoyo.

Parasolid: Industry Standard & Broad Ecosystem

• Origin: 1985, created by Shape Data Ltd. in the UK.
• Development & Ownership: Currently Siemens Digital Industries Software’s flagship product.
• Highlights: Embedded in hundreds of major CAD/CAM/CAE software globally; recognized as the “gold standard” for 3D geometric modeling; strong support for solid, surface, and convergent modeling (combining B-Rep & facets).
• Data Exchange: Uses XT file format for efficient interoperability.
• Key Users: Siemens NX, Solid Edge, SolidWorks, Onshape, MicroStation, IRONCAD, Shapr3D, and others.

CGM: Exclusive Power for Major Corporations

• Origin: Officially integrated into CATIA V5 in 1999, developed by Dassault Systèmes (France).
• Development & Ownership: Owned and primarily used by Dassault Systèmes within their product suite.
• Highlights: Modern kernel redesigned under a “blank-page initiative” for demanding industries like aerospace, automotive, and heavy industrial equipment; excels in surface accuracy, large model management, and complex workflow optimization.
• Licensing: Mainly internal use in CATIA, 3DEXPERIENCE but now available independently for select partners in robotics and manufacturing.
• Key Users: Dassault CATIA, 3DEXPERIENCE, Stäubli Robotics, Mitsui Zosen.

Quick Comparison Table of the Three Leading Kernels:

Considerations When Exchanging Native CAD Files Among Different Kernels

• Kernel Differences: Each CAD software uses its own geometric kernel (e.g., Parasolid for SolidWorks, ACIS for AutoCAD, Granite for Creo), significantly affecting compatibility. File conversions among software with different kernels often result in data loss or slight geometry deviations.
• Best Practice: Conversion within the same kernel family (native-to-native or native-to-kernel) preserves geometry quality best. For example, exchanging Parasolid (.x_t) or ACIS (.sat) files between software using the same kernel minimizes loss.
• Neutral Formats: When exchanging data between different kernels, neutral formats like STEP (.stp, .step) or IGES (.igs, .iges) are widely used but may lose constraints, assembly structure, or small details.
• Repair Tools: Some CAD software have import repair features to rebuild or fix geometry after neutral file imports, reducing errors. SolidWorks and Fusion 360 offer such functions.
• Recommendations: Prefer exchanging native or kernel-specific files when possible. Otherwise, use STEP AP242 or QIF standards for better interoperability and model-based definition preservation.

Reverse Engineering Applications at PSH Design to Create Native Negative CAD Files

• Professional Process : PSH Design employs cutting-edge 3D scanning technologies to capture point cloud or mesh data from physical samples. Specialized software then converts this data into parametric CAD models or NURBS surface models per customer requirements.
• Wide Format Output: PSH Design can produce nearly all standard native CAD file formats on the market such as SolidWorks, Autodesk Inventor, PTC Creo, Catia, NX, including hybrid or surface models, catering to manufacturing and aesthetic design needs.
• Manufacturing and Aesthetic Optimization: By integrating high-quality Class-A surfacing with reverse engineering, PSH Design ensures the negative CAD files are technically accurate and visually refined for industries like automotive, motorcycles, yachts, and premium home appliances.
• 3D CMM Measurement and Inspection Support: PSH Design provides precise measurement services and generates scan-to-CAD inspection reports to guarantee product compliance.
• Free Consultation and Testing: Clients can submit project requests for free consultation, quotes, and initial test services before formal project commencement. Contact for free test project at link : https://pshdesign.com/rfq-free-test-project/

Conclusion : 

• Parasolid remains the most widely adopted kernel in the market, leading in software integrations and data exchange standards.
• ACIS offers flexibility and numerous variants, serving a broad range of industries and companies developing custom CAD solutions.
• CGM serves as the high-tech core for large industrial corporations requiring tailored CAD solutions and complex workflows, especially in aerospace, automotive, and heavy equipment sectors.
• File exchanges of native CAD files between different kernels need careful management to avoid data loss, favoring native or kernel-specific formats when possible. Neutral formats like STEP should be handled with software capable of import repair.
• For generating native negative CAD files, PSH Design uses a rigorous reverse engineering process combined with modern scanning and software, delivering precision and aesthetics aligned with client manufacturing requirements.

(PSH Design Team )