# Methodology Proposal and 3D Model Creation of a Car Steering Wheel
## 2 Methodology of Vehicle Steering Wheel Creation
### Preparatory Phase of the Proposal for the Vehicle Steering Wheel Creation
#### 2.1.3 Selection of Software Application  
The development of new CAD application functions allows their inclusion in the design of the creation of the steering wheel, opening up new possibilities for creating the geometry of virtual 3D models. Before selecting a suitable CAD application, we had to consider the following:  
* The design of both the lower and upper parts will be complex and will likely consist of advanced curve-based volumetric geometry generation functions. It will be necessary to create a number of spatial curves and planar sketches that will form the basis of the surfaces. The surfaces will additionally be smoothed by means of further so-called control curves in order to achieve a smooth transition. When volume is added, the desired shape is achieved without sharp edges with smooth transitions between different geometric shapes. * The virtual steering wheel model will consist of 5, 6 or 7 components, which requires the creation of an assembly. Within the new assembly, the other parts of the assembly should be created using dependent geometry (reference axes, planes, points, curves, which will create the so-called skeleton model) in a top-down design style, ensuring that, in case of any major change to the geometry, the designer will be alerted to the dependent geometry and will not make modeling mistakes. Top-down design is a process that progresses from a high-level design concept to a lower level. The high-level design concept is larger, broader and more general. The lower-level design concept is smaller, more specific and detailed. * In order to personalize the assembly according to the customer's requirements, it will be necessary to create a so-called generic model. The generic model allows you to select model parameters (dimensions, texts, elements of different kinds) that will vary. The values of these parameters are entered in the table so that one generic model becomes, for example, twenty virtual models. Such virtual models can be opened and written to disk, or they can be inserted into an assembly and written to disk by saving the assembly. The method of creating generic models saves time but requires the experience of the designer. Considerations about the complexity of the model led us to believe that it was appropriate to use parametric 3D CAD software. Our personal experience includes 4 parametric softwares. However, there are many more applications available on the market. According to [26], the following 8 parametric 3D CAD softwares are currently the most widely used: \begin{table}
\begin{tabular}{l c c c} \hline \hline
**Total Number of Assembly Members** & **5** & **6** & **7** \\ \hline Bottom part & 1 & 1 & 1 \\ Top part & 1 & 1 & 1 \\ Central decorative part & 1 & 1 & 1 \\ The number of arms of the lower part, affecting the number of & 2 & 3 & 4 \\ decorative parts & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Total number of steering wheel assembly members depending on the number of bottom arms. SOLIDWORKS--The software is intuitive, simple and designed to make the designer's work as easy as possible. Around 200 novelties are programmed each year, most of which have been created specifically on the initiative of users. It includes tools not only for 3D design but also for data management, simulations, electrical designs, plastic simulations, product inspection and CAM machining, thus covering the entire spectrum from development to production. Software license is charged [27]. 2. CATIA--The software offers a wide range of solutions integrated into one environment for all aspects and disciplines. It covers the areas of product design and development, working in 3D based on a single database, interfacing with PLM systems, supporting production without drawings, ensuring collaboration in teams and optimizing technological processes. Software license is charged [28]. 3. FreeCAD--It is an open-source 3D program with an intuitive interface that suits even beginners.