# Effect of Augmented Reality Support on Quality Inspection of Welded Structures
## 5 Discussion
Close collaboration with industry experts in the design of the AR approach and a pilot study to determine the limits of the proposed solution may have contributed to the high degree of applicability. The use of the HHD made it possible for the user to move freely at the workstation while inspecting the part without any restrictions related to the hardware. Three main hypotheses were defined and then tested during the experiment. The first addresses the effectiveness of the execution of the control task and the influence of the approach used on this effectiveness. The level of efficiency in the experiment was defined by the total time to complete the task, i.e., the speed with which the proband inspected the entire control set. This indicator was tested in two variants, namely with the support of the conventional inspection approach and with the support of the proposed AR approach. At the same time, the element of user experience was monitored. Statistical analysis provided evidence of a statistically significant difference in user performance depending on the weldment inspection approach. These results support the original hypothesis which predicted that using the AR approach would lead to faster completion of the inspection task compared to the traditional method supported by printed documentation. The findingssuggest that the AR approach has relatively greater benefits for a group of inexperienced probands than for experienced inspectors. The second hypothesis investigates the effect of the methodology used on the error rate. Overall, the results of the analysis can be summarised by stating that statistically significant differences in error rates were found between the data groups, however, the tests performed as part of the post hoc analysis failed to identify specific pairs of groups with significant differences. This finding suggests that more extended statistical methods or an increase in sample size would be appropriate for further research to obtain a more accurate and comprehensive analysis of the error rate data. The third hypothesis addressed the impact of the approach used on the level of perceived mental distress. During the experiment, it was statistically confirmed that the use of the conventional methodology showed a significantly higher mental workload compared to the AR approach. The highest levels of mental workload were observed for time and effort when using the conventional method. The smallest differences were observed in the area of performance. These data support the conclusion that the AR approach may provide benefits in reducing perceived mental workload compared to the conventional methods. Users also evaluated the usability of the proposed solution in the experiment. The usability scores were high, corresponding to the usability category rated as \"excellent\". The research presented here also has some limitations. The main one is related to the object detection method used. Unlike the image detection method, it does not require the use of additional markers in the scene, the inspected object itself serves as a target, and therefore, this method has a very high potential for deployment in industrial applications. However, unlike the image target method, it is not yet technologically possible to detect more than one object in a scene. Therefore, it is still necessary to combine these methods when recognising multiple objects. Further limitations are related to lighting conditions and tracking of the object. During the experiment, object target detection worked smoothly under standard lighting conditions at the workplace without the need to supply an additional light source. During a prolonged inspection or greater movement around the inspected part, at some points the visualisation disconnected from the target, and the scene needed to be re-anchored.