Augmented Reality (AR) is an interactive experience of a real-world environment. It is used in development, production, installation and maintenance processes. Augmented Reality is in a constant further development. (Zeilhofer-Ficker, p. 2)

Good opportunities to interact with the real world are portable hardware such as smartphones or laptops with cameras. On the monitor a user can overlay the physical world with a virtual reality to get useful information. The information displayed on the screen varies depending on the environment and the data from the AR app or the internet. (Seitz, p. 2)
For example, you can use AR for a crash test. A database with pictures of different accidents can be used to determine the damage of a real accident by comparing the pictures with each other. AR makes is possible to determine the exact damage without examining the accident car. (Zeilhofer-Ficker, p. 3)

For the implementation the AR system depends on three components. Those are the presentation, the tracking and the interaction. For the presentation of a virtual environment are 3-D computer graphics necessary. This virtual environment can be created via a 3-D rendering library. Tracking is the required technology to catch the position and movement of an object. The integration of interactions allows the user to operate with the AR system. (Tönnis, p. 8)

• The system's autonomy don't require external sensors and the application can be use in any enviourment without much preperation.
• Only costs for the development or acquisition of the app
• Infinite life span (not bounded to any hardware)
• Easy to combine with other indoor navigation technologys and data goggles
• Rapid dissemination possible
• Easy to operate with
• No meaningful disturbing factors

• Without combined hardware, the calculation for a optimal route can take a some time
• A bad quality of the smartphnoe camera or a dirty lens impair the indoor navigation a lot
• Strong dependency to the used smartphone (Performance and camera)
• Inaccurate in general without an other sensor technology
• User have to constantly paying attention to the smartphone
• A massive power consumption for the mobile phone battery

An AR system can be combined with other smartphone functions like GPS, WiFi or Bluetooth. Therefore, the AR system can use information from the other functions e.g. the location data. That makes indoor navigation with AR possible. The AR app shows the current position in a building and tells you the direction and how far you have to go next. To use AR as an indoor navigation without the help of sensors beside the camera you need AR markers. They can be detected by the camera and can be placed on walls all over the building. They're required for the app to identify the current position of the user. The accuracy of the marker can vary heavily depending on the used camera. Another disadvantage is the high battery consumption because of the continuous use of the monitor and the camera. Therefore, it is possible to combine the AR system with another sensor technology like Bluetooth low energy beacons (BLE) to preserve the battery power. (Barolli / Enokido, p. 147 f.)

Intel tested the mobile AR browser “junaio” and the indoor tracking via latitude/longitude/altitude (LLA) markers on their intel developer forum. The result was a handsome and original way to navigate the visitors through the intel developer forum as shown in the underlying picture. The AR channel offered the visitor real time information about conferences, location, panel discussions and sales in the whole building. Because of the flood of information, the users can filter them via keywords. This allows to choose easily and efficiently what kind of information will be provided. The metrics shows that approximately 9% of the visitors used the AR navigation. (Furth)

Indoor navigation at the intel developer forum

The “Kiosk Europe Expo” want to find an innovative and entertaining way to navigate their visitors through the conference. There AR channel allows the users a minute-by-minute information about panel discussions and the associated building position. The navigation is compass based information provided by a LLA marker technology. This allows a navigation without using GPS data and was the first implementation of an extended indoor navigation. (Furth)

They did a feasibility study in the university of Kassel to research the use of indoor navigation with a combined system of BLE beacons and augmented reality with test persons. The study shows a prototype that strikes a balance between a cost-intensive commercial overall solution and a time-intensive self made implementation. (Klose et al.)
The prototype uses an indoor navigation on the basis of augmented reality. They use data goggles to realize the navigation. The test environment is a 100 meter long route in two floors with 34 BLE beacons. The beacons where placed in a way such that it is able to receive at least three signals in every position in that route. The receiver of the signals is a smartphone. The variation of the position data of a test person is at the most 2 meters. The smatphone transfers the data to the data goggles and the test person sees the navigaiton information on the glasses. The costs for hard- and software was about 4,500 € and the installation and setting takes about two weeks. (Klose et al.)

A research of indoor navigation in a maintenance and repair environment has also taken place. For an efficient execution of his daily work a service technician can use an AR app for an interactive step by step instruction and a general description of e.g. a installation process. Overlapping of a virtual model and a real product can show relevant elements, like a pigmented bolt. It was necessary to install an additional IT infrastructure like WLAN or RFID dispatcher. An alternative way is to capture the complete inside of a building. The disadvantage of this method are changes. If some objects change their position you have to recapture the whole room. This is very time-consuming. (Neges)

Criterion	Description
Range	It is not very large. You can have a 2 meters distance between the marker and your smartphone. (Boll et al.,Ziegler Crossmedia Experts,Nubert Electronic GmbH)
Accuracy	It is not good. For an improved accuracy is another sensor like beacons necessary. It leads to problems with disturbing factors if you use AR as a standalone technology. (Simonsen) Marker based tracking systems haven’t a good accuracy. This attribute is dependent to the used camera and upload rate of the given hardware. Current smartphones are not powerful enough for the needed calculations. (Tümler)
Power consumption	The power consumption is very high. The usage of camera, sensors and in certain cases audio output on the same hardware is a power overconsumption. (Simonsen) Therefore, it is possible to combine the AR system with another sensor technology like Bluetooth low energy beacons (BLE) to preserve the battery power. (Barolli / Enokido)
Life span	The hardware life span is good. The marker has a long life span of over 5 years and the replacement of a marker is very cheap. (Fanghänel) There don’t exist any meaningful researches for the life span aspect of AR. The usage of AR can cause a physical and mental surplus load for the user. If this effect persists, the life span of AR isn’t very good. (Tümler) AR and VR are unique in that the technologies have the potential to touch so many different markets, use cases, and applications, allowing the opening up of a substantial addressable market. However, both technologies are currently in their infancy and face several challenges. (ABI Research)
Bit rate	Only good with additional sensors to apply a bit rate better than 100 ms. This amount is necessary to guarantee a good tracking function. (Boring) Existing mobile object/image recognition services such as Google Goggles, Kooaba and Snaptell give us only a hint of all the future possibilities. One problem with current solutions is the long lag, typically tens of seconds, between snapping the picture and receiving the response to the query. (Siltanen)
Disturbing factor	In a manufacturing environment no meaningful disturbing factors exist. The tracking system in this scenario is very solid. (Bade) Therefore, it can often lead to inaccuracies regarding ist current position, since the sensors can be influenced by external disturbances. (Einspieler)
Embedding (no additional Hardware required)	To show the AR projection you need a specific view distance. It's exhausting for the eyes to combine the virtual objects with the real world. This has a negative effect of the well-being of the user and results in a bad embedding. (Tümler)