When we talk about 3D Printing, 4D Printing or any other type of technology related to manufacturing, we mention about creating models digitally on our computers. These models that we are referring to are prepared using software and tools that are called as CAD software. CAD stands for Computer Aided Design. As we delve more into this article, we will be talking in detail about CAD, its types, pros & cons and all that you really need to know.
Computer-Aided Design: Introduction:
To put it quite simply, Computer Aided Design can be defined as a class of tools and software that help you in making digital models or technical illustrations of your projects.
If we delve a little into the history of CAD software, we can find out that initially, even the CAD software was restricted to designing and developing 2D models of products. With time and advancement in technology, CAD software is now able to build 3D models and even go as far as imagining the virtual reality of that model. Such software now allows us to input certain physical properties of the digital model such as the weight of the product, or material that may be put to use, etc.
The specialty of CAD software is that you are not restricted to any staple or basic geometrical shape; you can build any kind of complex 3D CAD model structure and set their physical properties. If you are building a large product, CAD software helps you to design each part separately and later, helps in the assembly of the parts. Apart from these points, CAD software helps you to test how your products will react to different kind of forces applied to them, the motion of your products in certain conditions, interaction with other materials including fluids etc. With the simulation and rendering, you can get a perfect idea of how your product will behave in a real-life scenario.
It is very clear that for any manufacturing enterprise or an engineering design company, CAD software is a basic necessity. With that cleared up, companies are often perplexed on what type of CAD software should they use. As the market is flooded with various CAD software, you may ask what the different types of modeling methodologies are, and the answer to that is:
- Surface Modeling
- Solid Modeling
- Polygon Modeling
Surface Modeling Methodology:
When we talk about Surface Modeling methodology, it is basically concentrating on the external facets of an object. Technically, it constructs an object by extending a surface over it along with the 3D curves that are produced by the designer. In hindsight, you are depicting the boundaries of the surface of an object.
In this type of modeling, the user can actually see entire surface points under which solid interiors are present. Surface models actually define the surface features, including the edges, of an object.
- Software Modeling allows for more free-form shapes.
- It is more definite in its nature. There is no unnecessary ambiguity in this modeling technique.
- Identification of complex surfaces is easier in comparison to other methodologies.
- More realistic approach
- The steps in Surface Modeling are not parametric and hence it can be hard to go back to make changes.
- It is rather difficult to construct.
- This methodology is more time-consuming in comparison to others.
- Surface Modeling also requires a large amount of storage space.
Surface Modeling is used in the following industries and applications:
- Because of its unambiguous and definite nature in defining the external facets of an object, Surface Modeling is being widely used in Consumer Good Products, Aerospace Industry, as well as Shipping industry to describe the exterior in the most suitable way.
- According to an IEEE published research paper by students of College of Information Engineering, Beijing, Surface Modeling has integrated several models with additional shape parameters and certain computer graph principles. This is why Surface Designing is chosen by Professional Product Designers who are able to visualize their designs at different angles and get better display effects.
This YouTube video will help you get a deeper look into the working and implementation of Surface Modeling.
Solid Modeling Methodology:
Solid Modeling methodology is often touted to be the easiest type of 3D modeling technique to use. 3D CAD models are developed by using the most basic of shapes that include cylinders, spheres, boxes, cones, and even tori (which is equivalent to the shape of donuts). These shapes can then be used together to create complex structures that you require. It is important to know that, by ‘using together’ we mean joining, subtracting and overlapping two shapes together.
It is mainly used for representing solid objects as 3D CAD models. It is also used in prototyping and product visualization. This methodology makes use of mathematical principles to create 3D CAD models.
- This methodology offers a feature of an intersection. You can join two shapes by cutting into the design of one of them. This offers better results in terms of shape and form. You can design an object in a more intricate fashion using Solid Modeling.
- Solid Modeling offers you a parametric process of designing. This means that you can separately look at the commands you have used during the designing process. This helps in fixing mistakes or making any change in the product.
- It is the most suited option for automated applications.
Even Solid Modeling requires a large amount of storage which can put off some of the users.
Manipulations may be complex and can take unwanted extra time to complete.
As Solid Modeling allows intricate ways of joining, it is being used by Engineering Design Professionals to visualize a product digitally.
Considering the parametric process offered by Solid Modeling, it is being used in Medical Industry for the designing of models based on internal parts of our bodies.
It is also majorly being used by Civil Engineers to create the layout of a certain building.
To get a more elaborate view on Solid Modeling, you can see this YouTube video on the same.
Polygon Modeling Methodology:
In this methodology, the 3D CAD models are created using polygons for representation and approximation. As polygons have infinite sides, it becomes possible to use them and develop a surface of any size.
When a large number of polygons are used to create 3D CAD models, these models can be called as a polygon mesh. Basically, a larger shape using a large number of triangles, quadrilaterals or other simple polygons is called a polygon mesh. This concept is largely used in polygon modeling.
- The main pro of this methodology is the fact that it is much faster than the other alternatives that we have discussed.
- This process is easier than others. Moving around and combining shapes is also comparatively easier.
- This methodology comes coupled with the texture maps. This leads to much easier editing in comparison to alternatives.
- Polygons are incompetent in properly representing the curved surfaces. Very often, thousands of polygons are required to represent detailed surfaces, which is not very satisfactory.
- Paint FX is a unique paint technology used in CAD models for creating paint effects in 2D as well as 3D objects. Unfortunately, Polygon Modeling makes it impossible to use Paint FX with individual polygons.
- Polygon Modeling is often the primary choice in Gaming Industries for building real-time computer graphics. This is because of Polygon Modeling’s good working with scanline rendering.
- Because of its greater control over geometry, Polygon Modeling is often used in developing complex human modeling in various industries.
You should also watch this YouTube video on Polygon Modeling to add to the above theoretical knowledge.
It can be rather confusing as to which methodology should one progress on given the stark differences in features offered by each one of them.
You need to do proper requirement gathering and analysis for your project. We have seen that each one of these methodologies has some kind of edge over the other. While Solid Modeling has been the most robust out of the three, Polygon Modeling has been the quickest, whereas Surface Modeling gives you more freedom over the curves. It is expected that you analyze the proper needs of your project, compare the pros and cons of each modeling methodology and then finalize the software based on the requirement. Hope this article helps you make a decisive decision.