There are many benefits to designing with 3D solids. Using powerful and highly sophisticated 3D sculpting software gives mechanical engineers and designers the ability to create incredibly complex objects and large assemblies quickly. Changes to a design can be done without the need to recreate all aspects from scratch for every iteration. Cloud-based technology makes sharing and storing projects easier and more secure and greatly facilitates collaboration between designers and stakeholders.
However, what is often lost when discussing 3D sculpting software is the differentiation between freeform design and parametric design. Some function using parametric solids and others rely on free-form solids. The distinction between the two can seem confusing for those who are new to three-dimensional computer aided (CAD) design. In this article, we will provide you with a brief description of both freeform design and parametric design and list the benefits of each type of system.
What is Freeform Design?
In relation to CAD modeling, freeform design is also known as direct design, freeform surface design, or freeform surfacing. Freeform surfaces are created using a set of points, known as a point cloud, or a polygonal mesh. These surfaces do not have inflexible radial dimensions. Examples of freeform surfaces include both Class A surfaces and technical surfaces for parts.
Freeform modeling is often used to design one-off structures, car bodies, the hulls of boats, turbine blades, and aircraft components. It is also often employed in the beginning stages of product design to define and develop a concept.
Freeform design software does not use set equations or rules when describing geometric shapes, only the topology of the object is stored in the software. Many freeform 3D sculpting software operates using a ‘push and pull’ interface, where users can manipulate geometric shapes directly. While the freeform design method gives users more conceptual freedom in how and what they create, it is not suited for products or parts that rely on complex inter-dependencies with other components.
Benefits of Freeform Design
Ideal for concept development Simple and fast
Can be used to accommodate unexpected design changes
Allows for the repeated investigation of different shapes and designs
What is Parametric Design?
Unlike direct freeform models, 3D features that are made using parametric design software are created according to pre- programmed algorithms that provide the parameters for the shapes. There are two types of parametric modeling systems:
Propagation-based parametric systems: Algorithms are used to create totally new shapes based on parametric input Constraint parametric systems: Fundamental constraints are set at the beginning of the process and algorithms produce shapes that comply with the fundamentals
CAD parametric modeling tools remove the need for a designer or engineer to completely redraw a design every time a change is made. For this reason, parametric modeling is of more use when working on projects involving iterative designs that must be developed in several variations. Once a designer has created a parametric solid model, they can then easily and quickly change and modify it through multiple sets of drawings.
Despite its many benefits, there are some drawbacks to 3D parametric solid modeling systems. When using parametric design software, a user must define solids according to what changes may need to be made to the design and what relationships will exist between different design features. This requires a high degree of skill on the part of the user. Additionally, unanticipated issues can impact the set parameters of design, resulting in the need to scrap the design entirely and begin again.
Benefits of Parametric Design
Automatic updates reduce design iteration time Families of components and parts can be created easily
Design features for multiple mating components can be created quickly
Designs can be easily integrated with manufacturing processes
How to Decide Which 3D Sculpting Software to Use
The process of creating a new product, component, or piece of machinery is often not linear. Designers and engineers must be able to have the flexibility to adapt their designs to accommodate unforeseen issues at every stage. For this reason, most experts choose to use CAD 3D sculpting software that incorporates both freeform modeling and parametric modeling capabilities.
Combining both of these systems within one piece of software allows designers to create complex models that can be easily adaptable at any time.
A prime example of this type of software is 3D Sculptor from Dassault Systèmes. 3D Sculptor provides designers and engineers with powerful freeform and parametric modeling tools that can be used to create highly complex shapes.
3D Sculptor is a cloud-based program that works in conjunction with Dassault Systèmes’ 3DEXPERIENCE platform. Once a design has been produced, users can store it securely on the cloud and easily collaborate with other team members. Advanced programs such as 3D Sculptor allow creators to fully explore their ideas and arrive at more innovative solutions using both freeform and parametric designs.