# Augmented Reality for PCB Component Identification and Localization
## 5 Results
### Experiment 2
#### 5.2.2 Component Identification Correctness Analysis  
Identification correctness evaluates participants' ability to correctly identify PCB components based on the AR system's augmented positions. The correctness of users' responses was determined by assessing whether the indicated position fell inside or on the boundary of each component's mapped area (center, size, and shape). A component was deemed correctly identified if the indicated position was within the mapped boundary; otherwise, it was considered incorrect (see Figure 14). The highest correctness was observed at 90\({}^{\circ}\), where participants correctly identified an average of 10 out of 12 components. At this angle, the augmented and indicated positions were closely aligned with the reference position, resulting in minimal errors and enabling more accurate identifications. At a 60\({}^{\circ}\) viewing angle, correctness decreased to an average of 7 out of 12 components and was lowest at 45\({}^{\circ}\), with only 5 out of 12 correctly identified components on average. The scatter plot in Figure 13 shows observations at 45\({}^{\circ}\) and illustrates what was found earlier. Users seemed to compensate for large errors in the augmented marker positions (see, e.g., components 22), allowing them to still determine the correct component. Also, the spatial pattern and distribution of indicated positions are,  
Figure 14: Component identification correctness at the 45-degree viewing angle. (Colored dots represent user-indicated positions cluster for each component. Each color corresponds to a different component, while black squares and circles represent the true component boundaries as defined in the PCB layout). Figure 13: Errors in augmented and identified positions across all angles. quite expectedly, similar for all components regardless of component size, meaning that the likelihood of correctly identifying a component increases for larger components. The analysis also reveals that components placed near the edges of the workspace, such as P7 and U4, were identified with greater correctness, possibly due to reduced visual clutter. In contrast, centrally located components in denser regions showed higher variability in indicated positions. Altogether, these observations showcase the influence of component size, shape, spatial arrangement, and viewing angle on identification correctness, with larger, circular, and isolated components being easier to identify, even under oblique viewing angles. The component identification correctness, as defined in this analysis, serves as an intuitive measure to assess the usability of the AR-based augmentation. By comparing the spatial \"footprint\" of a component with the user-indicated positions, this metric tends to favor larger components with a uniform, convex structure (e.g., P7 and U4), which are more easily aligned within the AR overlay. However, it penalizes smaller or elongated components, such as resistors or SD card connectors, which often have narrow footprints and are more sensitive to angle and orientation. This introduces a geometric bias that should be considered when interpreting identification accuracy across diverse component types. The alternative to not correctly identifying a given component on the PCB is either not identifying a component at all or mistakenly identifying another component near the intended component. The likelihood of opting for such an incorrect nearby component depends naturally on the component density of a given PCB and how far away the identified positions are from the intended components' borders. We, therefore, include in our analysis another measure that indicates the shortest distances of identified positions from the intended component boundaries. The plot in Figure 15 provides an account of the distances from component boundaries for the identified and augmented positions at different viewing angles. As the viewing angle becomes more oblique, the distances and variabilities increase.