# Augmented Reality-Based Framework Supporting Visual Inspection for Automotive Industry
## 2 AR in the Industry  
In this work, AR is the adopted technology for data visualization. AR Attempts to integrate information/ virtual models, such as computer graphics, texts, sounds, and other modalities, into the physical environment so that users understand this information as existing in real-time. Real-time communication represents a key role and remains a challenge for AR applications implementation [11]. According to [7], a standard AR system is composed of four essential components. First, the visualization device could be Head-Mounted Display (HMDs), Hand-Held Devices (HHDs), statistic devices, and projectors. Second, the camera, is a fundamental component in the AR system to display the environment. Third, a tracking system serves to bring the virtual objects precisely into the real environment. The tracking system can be categorized into two main classes regarding AR purpose and applications: marker-based tracking and markerless tracking [12]. However, marker-based AR is the most common AR technology used [7] since it provides better accuracy with an easy implementation [12]. Marker-based systems rely essentially on the use of a visual marker [13]. Marker recognition by AR applications brings virtual information into the real world. In contrast, markerless systems [14] provide visual data by calculating, for example, the user location. In a production environment, considering the effects that a too high cognitive load has on human performance, implementing such technology can potentially have a significant effect on the result of the same quality and productivity [15]. Moreover, in a recent paper by [PERSON] et al. [16], authors have highlighted the staple need for visual computing technologies taking into account AR to support the operator inside the 4.0 industries. Over the past years, the fact of productivity and quality growth when using AR, encourages researchers to work on the integration of such technology in the manufacturing environment [11]. The focus of recent research on the industrial field shows mainly the following use cases of AR: assembly, maintenance, and training activities. However, as best as we know, very few publications are available in the literature that addresses the issue of inspection based on AR, which denotes the huge gap in the literature related to real use cases of AR implementation for inspection activities. [PERSON] et al. [17] have also found that most of the works are concentrated on maintenance and assembly presenting a research gap in the AR-assisted inspection. Moreover, authors in [17] have affirmed that the majority of existing works are not only limited to maintenance and assembly tasks but also represent principally conceptual frameworks for AR use. The reason behind this is the lake of specific standards and guidelines in general during the implementation of AR and particularly for inspection [17]. Besides that, bringing out AR from laboratory areas to real use-cases inside industries uncovers several challenges that may explain the main ground behind the huge gap of works related to AR for inspection. Most of the existing issues are related to security problems, hardware compatibility and weight, and the proper functioning of the software in a real industry environment which is exposed to a lot of factors such as dust, ergonomic reasons, and especially human acceptance of the technology [7,18,19]. Focusing on the automotive field, operators nowadays must deal with a huge amount of data during vehicle production or even during the diagnostic phase. In most automotive industries, the vehicle information is accessible through a station next to each production phase or even in a document on the vehicle itself. In these cases, for inspection tasks, the operator faces the timing issue to assist and repair the vehicle defects. The time needed to accomplish the inspection activities is more and more demanded to be decreased in the automotive industries, notably for those producing the high-tech vehicles where the finished car inspection requires a long time [20].