# Augmented Reality Applications in Industry 4.0 Environment
## 5 Discussion
### Implementation of AR in Companies  
The issue of application of AR technology in different segments of the industry has been addressed in many papers. In particular, useful instructions for the implementation of AR in manufacturing companies are given in [48,111]. In addition to research in the field of application relative to AR applications in the industrial environment, which are currently more related to solving technical problems, it is necessary to intensify research with respect to the impression of users, ergonomics and usability of applications. A good starting point in this case could be the innovative procedure for selecting AR maintenance technology, which is user-oriented, proposed by [117]. Nevertheless, according to [118]: Every company requires an implementation plan that introduces the application of AR into its business, while simultaneously expanding its capacity for further development and use. Based on the literature and personal experiences of the authors, the process of applying AR applications in companies can be realized through five steps:  
1. Define the goal for the AR application. Many different tasks and subtasks can be performed or improved using AR technology, but may require different levels of technology and complexity. For example, in order to view assignments or examples from a workbook using AR [113], you only need to install the appropriate AR application on your smartphone. However, specialized head mounted displays or smart glasses are likely to be required to enhance maintenance or assembly tasks, along with appropriate software with dynamic 3D models of the environment. 2. Create your own digital content. The AR application consists of software, hardware and digital content presented in an innovative manner. Software and hardware can be easily purchased, but digital content, as the core of the application, is a unique asset of the company and should be created within the company. In order for an object to be presented in an AR application, it needs to be digitized. This can be achieved by customizing existing 3D models of products and/or machines and devices or by creating new ones using 3D modelling or 2D or 3D scanning. In any case, it is strategically wise to make a list of existing digital assets in 3D and other representations in addition to all useful assets of the company. However, the transforming procedures (assembly instructions, machine repair guidelines, design procedures, etc.) into digital content suitable for AR application are complex and usually requires a team that consists of company technology experts and AR experts. Define the location of the AR device and interconnecting object. Different technologies can be used to determine the position of the AR device and the interconnecting object. Three types are used:  
* GPS positioning; belongs to the group of so-called unregistered AR experience and is limited by the accuracy of the GPS system;
* Marker based; use QR codes, bar codes, logos or a specially designed symbols. Markers should be placed at visible points in the environment and the AR user should know where to point his AR device;
* Machine vision is the most powerful approach in environment recognition and it allows the use of AR in an unstructured environment. Tt requires high quality software and hardware, but in some conditions (low lighting, etc.) it is still unable to recognize the object. * Define the required equipment. For the simplest AR applications, smart devices such as smartphones and tablets are quite sufficient. Most AR applications for manufacturing and assembly require universal HMD that can free the user's hands. There are many such devices available on the market. High-value AR applications, especially in the automotive, aircraft and pharmaceutical industries, use dedicated and very expensive AR HMDs. It is strongly recommended that companies use a multi-platform approach that allows AR experiences to be distributed across multiple platforms. * Define the required type of software approach.