# Augmented Reality for PCB Component Identification and Localization
## 5 Results
### Experiment 2
#### 5.2.5. Usability and User Experience  
The usability of the HoloLens(tm) 2 AR headset for identifying PCB components across three viewing angles (45\({}^{\circ}\), 60\({}^{\circ}\), and 90\({}^{\circ}\)) was evaluated through a detailed participant feedback questionnaire. The survey addressed usability, interface design, physical and visual discomfort, marker precision, learning experience, and overall limitations. Responses were collected using a 5-point Likert scale, where participants evaluated statements or questions as follows:  
* Very Poor (1): Completely inadequate or unsatisfactory. * Poor (2): Significant issues or limitations. * Neutral (3): Acceptable, neither positive nor negative. * Good (4): Effective with minor limitations. * Very Good (5): Highly effective and satisfactory. The full questionnaire used for this evaluation is provided in Questionnaire S2 in the Supplementary Materials. Open-ended responses were also gathered to supplement quantitative findings with qualitative insights. Seven out of ten participants rated the usability of the HoloLens(tm) and Tracker application as either \"Good\" (4) or \"Neutral\" (3), indicating moderate intuitiveness with clear potential for improvement. Participants with prior AR experience navigated the interface more easily, while first-time users often rated usability as \"Somewhat Difficult\" (2), highlighting challenges related to interaction mechanisms. Several novice users emphasized the need for better onboarding resources, suggesting that clearer navigation guidance and a more intuitive interface could significantly enhance the user experience. Figure 17: Task completion time (in seconds) across viewing angles (90\({}^{\circ}\), 60\({}^{\circ}\), and 45\({}^{\circ}\)). (Each blue boxplot represents the distribution of completion times, with the red horizontal line indicating the median. Red “+” symbols denote statistical outliers). \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Viewing** & **Mean** & **Std Dev** & **Variance** & **Min** & \
\begin{tabular}{c} **25 th** \\ **Percentile** \\ \end{tabular} & **Median** &
\begin{tabular}{c} **75 th** \\ **Percentile** \\ \end{tabular} & **Max** \\ \hline
90\({}^{\circ}\) & 3.26 & 1.81 & 3.28 & 1.26 & 2.16 & 2.59 & 3.40 & 8.46 \\
60\({}^{\circ}\) & 2.48 & 0.69 & 0.47 & 1.36 & 1.96 & 2.46 & 2.83 & 4.22 \\
45\({}^{\circ}\) & 2.45 & 1.25 & 1.57 & 0.97 & 1.31 & 2.28 & 3.10 & 6.25 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Descriptive Statistics of Task Completion Times by Viewing Angle (in seconds). Feedback on the Tracker application--the AR interface used for marker-based component identification--was mixed. While many participants appreciated its utility in guiding users to the correct components through visual overlays, some noted issues, such as delayed responsiveness and difficulty achieving stable marker alignment, which affected the precision of the AR overlay on the physical PCB. Suggested improvements included enhancing the application's responsiveness and incorporating clearer, more intuitive interaction cues to support more reliable tracking and guidance. Discomfort related to both the physical and visual aspects of the HoloLens(tm) headset was frequently reported. On the physical side, participants mentioned the weight of the device and the pressure from the straps around the head and nose. Five out of ten participants expressed concerns regarding prolonged use, with comments such as \"The headset felt heavy after a few minutes\" and \"The straps were difficult to adjust for comfort\". Visual discomfort was also a recurring issue. Participants reported difficulty focusing, compatibility problems with glasses, and flickering or misaligned markers in the AR overlay. These issues were particularly noticeable at oblique viewing angles (e.g., 45\({}^{\circ}\)), where tracking instability often led to reduced performance. As one participant noted, \"The flickering markers made it difficult to maintain focus\".