# User Preference-Based Method for Characterizing Automotive Wheel Hub Styles
## 2 Materials and Methods
### Data Material
#### 2.2.3 Design Element Reconstruction  
In current design practice, designers in enterprises play a central role. They focus closely on user needs and design goals. They rely on their own subjective design experience and creative thinking to create designs. The logic of the style characterization of design and its results must align with the cognitive logic and judgement of designers. The cognitive characterization of design simulates the cognitive logic and thinking mode of designers. It requires analyzing and characterizing the intrinsic connection between styles and styling design elements. This analysis occurs across the dimensions of design intention, drawing behavior, and functional structure. Firstly, this study involves 10 senior corporate designers. They deconstruct and analyze design elements in wheel styling. The front view of the wheel reveals two major components: the rim and the spokes. The rim, the peripheral round part of the wheel, mounts the tire and supports the vehicle's weight. Its styling features are relatively singular and less variable. The spokes, which support structure connecting the axle and the rim, vary in shape and quantity by vehicle model. They are the focal point of wheel styling design. This study summarizes wheel design elements into five categories: spoke layout, spoke shape, spoke number, spoke width, and center shape. Each category is further subdivided, with a detailed elaboration and explanation provided for each subcategory. 1. Spoke layout classification involves the arrangement pattern of the spokes. It shapes the overall shape and basic direction of the spoke profile. This is a key factor in determining the visual impact of the spoke profile. The study systematically summarizes and classifies spoke profiles from 255 wheel samples. The spoke layout is divided into four main categories: point line, petal, rotating, and netted. The point line type refers to spokes radiating outward in a straight line from the center point. The petal type \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Method** & **Cluster Quantity** & **Style Consensus (\%)** & **Computational Cost (min)** \\ \hline Manual Categorization & 9 & 76.5 & 180 \\ K-means (Raw Pixels) & 7 & 63.1 & 97 \\ ResNet-50+HC & 8 & 79.8 & 34 \\ VAE-DBSCAN & 7 & 81.2 & 13 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison of the results from the four clustering methods. Figure 3: Clustering results for wheel samples. describes spokes spreading out like flower petals. The rotating type is characterized by twisted spokes forming a rotating visual effect. The netted type involves spokes expanding outward and intertwining to form a mesh structure. The classification of spoke layouts is shown in Figure 4. 2 The spoke shape classification is a key aspect of wheel design. The spokes are the core component of the wheel shape. Their design characteristics are repetitive and regular, arrayed around the center. Consequently, the study of spoke profiles focuses on the morphological characteristics of a single spoke. This study analyzed and summarized the spoke characteristics of 255 previously collected wheel samples. The spoke profiles were classified into six basic forms: V-shaped, polygon-shaped, Y-shaped, rectangles, irregularly shaped, and curve-shaped. The classification of spoke shapes is presented in Figure 5. 3 The classification of the number of spokes is based on the wheel design. A single spoke serves as the basic unit, arranged in a circular array. The number of spokes directly impacts the visual sense of sparseness and density, influencing the viewer's sensory experience. This study details the count of spokes in the 255 previously collected wheel samples. The samples are classified into five categories: one piece, three piece, four piece, five piece, and seven piece. The one piece category refers to a single spoke in the shape of a disc. The three piece category includes designs with a number of spokes divisible by three.