Difference between Nurbs surface and Parametric surface in 3D Reverse Engineering


3D Reverse engineering is the process of reconstructing an object or component from existing physical parts or 3D data. In the field of CAD and product design, several types of surfaces can be used to represent 3D shapes, including Nurbs surfaces and Parametric surfaces.

Nurbs (Non-Uniform Rational B-Splines) surfaces are mathematical representations of curves and surfaces that are defined by control points and knots. They are widely used in computer-aided design, animation, and computer graphics because of their ability to represent complex shapes and their smoothness. Nurbs surfaces are defined by a set of curves called control curves, which define the shape and form of the surface. They are flexible and easily edited, making them ideal for creating highly accurate and complex shapes.

On the other hand, Parametric surfaces are defined by a set of mathematical equations defining the shape of the surface. They are often used in the design of objects with more straightforward shapes, such as cylinders and cones, but can also be used to create complex shapes. Parametric surfaces are defined by parameters such as length, width, radius, height, and angle, which can be adjusted to change the shape of the surface.

One of the key differences between Nurbs and parametric surfaces is the level of control and precision each offers. Nurbs surfaces offer a high level of control and precision, making them ideal for creating complex shapes and curves.

On the other hand, the parametric models offer a process where the dimensions and properties of a design are controlled by parameters or variables rather than fixed values.

Here are some of the key differences between Parametric modeling and NURBS Modeling

Nurbs Surface Parametric Surface
Made of Nurbs Patches
Made of Features
Editable by accessing the control points or patch network
Parameters are Editable by accessing the modeling tree
Appropriate for Organic Shapes
Appropriate for Prismatic Shapes
Contains patch network to edit the surface smoothness
Contains parametric modeling history for editing
Shape of the final scan to CAD model can't be changed, we can enhance the smoothness and details
Shape of the reverse engineered model can be changed
Used for simulation, animation, visual effect
Used for manufacturing product design
Can be exported as dumb solid, or surfaces
Can be exported as dump solid surface and parameters can be transferred to CAD software


In conclusion, both Nurbs surfaces and parametric surfaces have their own unique advantages and disadvantages. The choice between them will depend on the specific requirements of the reverse engineering project. If accuracy and scan-to-surface conversion speed are paramount, Nurbs surfaces may be the preferred choice. However, if design modification and design intern are more important, parametric surfaces may be a better option. Ultimately, the choice between Nurbs surfaces and parametric surfaces will depend on the needs and goals of the specific project.

Whats next:

Enquire Now


Leave a Comment

Your email address will not be published. Required fields are marked *