BimScaler Blog – Surface modeling in CAD is the process of creating and manipulating 3D models with surfaces rather than solids. The two most common types of surface modeling are non-uniform rational basis spline (NURBS) and polygonal modeling. Surface modeling provides advantages such as smoother designs, greater flexibility, and the ability to create complex shapes precisely.
Let’s take a closer look at surface modeling, including its definitions, applications, and benefits.
Surface modeling in CAD is a mathematical technique used to create detailed, three-dimensional models of objects.
Surface modeling is widely used in CAD to create illustrations, architectural renderings, and 3D animations. It enables designers to create realistic textures, smooth surfaces, and highlight flaws. Surface models, unlike solid models, cannot be opened to reveal internal workings and must be geometrically correct.
Automotive design is a typical field in which surface modeling is used. Surface modeling techniques are widely used in car body design to achieve aerodynamic shapes and svelte curves. With more flexibility, designers can create complex designs by defining surfaces instead of solid volumes.
Before we get into surface modeling, you may want to look into other design topics. Design for assembly is one of them that you may want to explore. DFA is a set of principles that aim to streamline manufacturing processes by making assembly easier and more efficient.
Learn more about it in our previous post, Design for Assembly: Definitions, Principles, and the Differences from DFM
Read more about it in our previous post, ‘Design for Assembly: Definitions, Principles, and the Differences from DFM‘.
The Different Types of Surface Modeling
There are 4 known different types of surface modeling, which are: NURBS, polygonal, subdivision, and implicit modeling. The types of surface modeling methods designers use depend on the shapes they wish to create and the scope of the surface modeling software they are using.
Let’s take a look at how each type of surface modeling works.
NURBS (Non-Uniform Rational B-Spline) modeling
Complex mathematical equations are used in NURBS modeling to produce realistic circles, arcs, and 2D surfaces that are then used to draw incredibly accurate, flexible, and lifelike 3D models.
Polygonal modeling
This software generates 3D structures from basic units known as tris (triangles) and polys (polygons), which are two-dimensional shapes with vertices and edges. This type of software is especially useful in situations where exactness or precision is not a major concern.
Subdivision modeling
Subdivision modeling involves breaking down a model’s polygon count into even fewer constituent parts. This gives a model more detail and a smoother appearance for the designer.
Implicit modeling
With implicit modeling, an object’s dimensions are defined by the software through the use of mathematical formulas. When constructing extremely complex shapes, implicit modeling can be used to save time.
Techniques and Tools for Surface Modeling
Surface modeling includes a range of methods and resources suited to various design requirements.
According to the 3DS blog, blending, sweeping, and lofting are a few typical methods. Creating surfaces between two or more profiles is known as lofting, and it’s perfect for crafting organic shapes like aeroplane fuselages or vases. Extruding a profile along a path is called “sweeping,” and it’s useful for making railings and pipes. Blending is the process of smoothly combining two surfaces, making it ideal for changing shapes.
Many tools for surface modeling are available in CAD software, ranging from simple sketching tools to sophisticated surface manipulation features. With the help of these tools, designers can easily sculpt, refine, and analyse surfaces. Surface filleting, curvature analysis, and surface editing tools are some of the features that enable designers to precisely refine their designs.
What is Surface Modeling Used for?
Product development and industrial design teams frequently use surface modeling. Surface modeling is freeform, so designers don’t need to build physical prototypes in order to create highly detailed representations of proposed products. Prior to the product entering the manufacturing phase, design flaws can be examined and found.
The 3DS blog also goes into great detail about how surface modeling can be used in automotive design, aerospace design, architecture and construction, and medical imaging.
Surface modeling techniques are used in automotive design to produce Class A surfaces. Surface modeling techniques are the only way to digitally replicate the intricate curvatures of automotive bodies.
In aerospace design, many aircraft designers use subdivision modeling methods to create aerodynamic configurations. That’s because aerospace design requires complex curvatures and free-flowing shapes.
In the architecture and construction industries, surface modeling is widely used to provide realistic depictions of what proposed building projects will look like. Architects, like those in the automotive and aerospace industries, use surface modeling techniques to design thin-walled structures.
Another use case for surface modeling is medical imaging. With surface modeling, researchers can track the progress of a disease and analyse the outcome of various treatment options.
Advantages of Surface Modeling
Surface modeling has a number of advantages in CAD. The flexibility, freeform shapes, and definitive nature, as well as the realistic approach, are some of the primary advantages of using surface modeling methods in CAD.
Aside from that, here are all of the benefits and advantages of using the surface modeling method in CAD.
- Flexibility: Surface modeling allows for the creation of highly complex and lifelike organic shapes that would be difficult or impossible to create with solid modeling.
- Freeform Shapes: Surface modeling enables the creation of more free-form shapes, as it focuses on the external facets of an object.
- Definitive Nature: Surface modeling is more definitive in nature, with no unnecessary ambiguity in the modeling technique.
- Easier Creation of Complex Surfaces: Surface modeling makes it easier to create complex surfaces compared to other modeling techniques.
- Realistic Approach: Surface modeling provides a more realistic approach for creating free form objects.
- Visual Representations: Surface modeling is commonly used to create visual representations of products, mechanical objects, or organic shapes like humans or animals.
- Iterative Refinement: Surface modeling promotes iterative refinement, allowing designers to make design changes and improve the model over time .
- Detecting Design Flaws: Surface modeling aids in detecting and rectifying potential design flaws, ensuring precision and smooth transitions between different design elements.
- Visualisation: Surface modeling is widely used for animations, video game characters, special effects, and product and architectural visualisations.
- Combination with Other Techniques: Surface modeling is often used in conjunction with solid modeling to create complete 3D models that show both exterior and interior details.
These advantages make surface modeling a valuable tool for designers and engineers in a variety of industries, allowing them to create detailed, lifelike models and visualisations. However, keep in mind that surface modeling does not provide a one-size-fits-all solution for your industry. Make sure to look into other modeling methods that may be applicable to your work.
For example, if you are designing infrastructure projects such as buildings, roads, or bridges, you might want to use civil engineering design.
Civil engineering design is a multidisciplinary approach to planning, analysis, design, construction, and maintenance that aims to create safe, sustainable, and efficient structures that meet society’s needs.
More about it in our post, ‘Civil Engineering Design: Definitions, Process, and Types of It‘.
Conclusion
Finally, surface modeling is a powerful tool in the CAD designer’s arsenal, providing unparalleled precision and creativity in design. Understanding the principles, techniques, and benefits of surface modeling allows designers to take their designs to new heights of excellence.
Combining surface modeling with BIM (Building Information Modeling) in construction projects can assist designers in creating detailed and realistic representations of building exteriors and interior spaces. This integration enables accurate visualisation of architectural elements and materials, which improves the overall design process.
That is why, for best results and efficient collaboration among all stakeholders, you should use BIM and surface modeling in your construction project.
So, are you ready to implement the BIM process for your construction project?
BIMscaler’s consulting and management services will provide you with end-to-end BIM usage for your project, starting with BIM/model management, content management, project start-up, project meetings, and end-user support, including as-built documentation creation.
As a leading Australian provider of BIM services, BIM Scaler assures you of a professional and effective BIM implementation for your building project.
