Reverse engineering:
Surface modeling, parametric modeling, volume modeling

on the basis of 3D scans

Reverse engineering is an essential process in modern product development, in which existing physical objects are digitally reconstructed in order to make design improvements, optimize manufacturing processes or create spare parts. In particular, the techniques of surface modeling, parametric modeling and volume modeling play a decisive role in the reconstruction of objects on the basis of 3D scans.

We describe the different types of reverse engineering, their areas of application and advantages. We will of course be happy to clarify the most suitable type of reverse engineering for your project. Simply get in touch with us.

1. surface modeling (reverse engineering)

Surface modeling, also known as reverse engineering or surface modeling, describes the process of converting 3D scan data (point clouds or meshes) into a mathematically defined model consisting of NURBS surfaces (Non-Uniform Rational B-Splines). This method is primarily used for free-form surfaces or complex organic geometries that cannot simply be described by standardized geometric shapes.

Characteristics of surface modeling:

  • Creation of smooth and continuous surfaces from point clouds or polygon meshes.
  • Ideal for replicating organic shapes such as vehicle bodies, consumer goods or medical implants.
  • Use of NURBS (Non-Uniform Rational B-Splines) for the precise representation of curved surfaces.
  • High flexibility for processing and modifying individual surface segments.

Process of reverse engineering:

  1. Data acquisition: 3D scan of the object (laser or structured light scanning).
  2. Point cloud processing: Cleanup and simplification of raw data.
  3. Mesh creation: Conversion to a polygon mesh (e.g. STL file).
  4. Surface approximation: Adaptation of NURBS surfaces to the mesh.
  5. Optimization: Ensure smoothness and seamlessness of the surfaces.

Advantages of surface modeling:

  • Perfect reproduction of complex designs and free-form surfaces.
  • Possibility of modification for design iterations.
  • Compatibility with common CAD systems.

Application areas of surface modeling:

  • Automotive industry (e.g. body parts, seat design).
  • Aerospace (wings, aerodynamic structures).
  • Medicine (prosthetics, individual implants).
  • Art and monument preservation (reconstruction of sculptures and artifacts).

2. parametric modeling

Parametric modeling is an advanced method for creating 3D models in which geometric dependencies and parameters are used to create a flexible and rule-based model. The relationships between the components are defined in the form of parameters, which means that changes at one point are automatically taken into account at other affected points.

Characteristics of parametric modeling:

  • Models are based on rules and relations (e.g. distances, angles, radii).
  • Modifiability by adjusting parameters without complete remodeling.
  • Support through feature-based modeling (drilling, milling, extrusion).
  • Precise control over design modifications and variations.

Process of parametric modeling:

  1. Definition of parameters: Definition of quantities, relationships and formulas.
  2. Design structure: Creation of the geometry based on predefined sketches.
  3. Feature hierarchy: Application of processing (e.g. extrusions, roundings).
  4. Validation and simulation: checking the model specifications.

Advantages of parametric modeling:

  • Quick adjustment through parameter manipulation.
  • Enables design iterations in the shortest possible time.
  • Better team collaboration through defined design rules.

Application areas of parametric modeling:

  • Mechanical engineering (precision components, prototypes).
  • Product design (consumer electronics, household appliances).
  • Architecture (modular systems, structural optimization).
  • Toolmaking (injection molds, die casting).

3. volume modeling

Solid modeling is a technique used to create three-dimensional objects by mathematically describing the entire volume of the object. In contrast to surface modeling, which focuses on surfaces, solid modeling enables a complete description of the internal and external geometry of an object.

Features of volume modeling:

  • Objects are defined as complete solids.
  • Enables physical simulations and strength analyses.
  • Detailed material properties can be assigned.
  • Facilitates production through direct transfer to CAM processes.

Volume modeling process:

  1. Creation of basic solids: construction from simple solid elements (cube, cylinder, etc.).
  2. Combinatorial operations: Boolean operations such as union or difference.
  3. Detail modeling: Adding features (drill holes, chamfers).
  4. Simulation and validation: verification of material properties and load.

Advantages of volume modeling:

  • Very precise and robust representation of objects.
  • Ideal for manufacturing processes and simulations.
  • Compatibility with modern production systems (CNC, 3D printing).

Application areas of volume modeling:

  • Metal processing and CNC machining.
  • Additive manufacturing (3D printing).
  • Machine and tool construction.
  • Design of technical components.

Which modeling method is suitable for your project?

The choice between surface modeling, parametric modeling and volume modeling depends heavily on the requirements of the project:

  • Surface modeling: Best choice for complex, organic or free-form objects.
  • Parametric modeling: Ideal for iterative product development processes and precise control options.
  • Solid modeling: Perfect for technical applications, manufacturing and structural analysis.

Thanks to modern reverse engineering technologies, precise digital models can be created that can be used for production, design optimization and archiving.