In closed rooms, like trade fairs, shopping centers or airports, the GPS signal becomes too weak and makes targeted indoor navigation impossible. However, Bluetooth beacon indoor navigation would be a welcome help for the way to your destination. In this article, I will explain the Bluetooth beacon indoor positioning. I also introduce you to the app with which we can experience the concept.
Motivation to Deal With the Bluetooth Beacon Indoor Navigation
Every time I visited a trade fair, exhibition or similar event, I got into the following situation: At the entrance, I received a flyer with a site plan of the event and a brief description of each stand.
The first thing I tried was to find my own position on the map. Then I looked for stands that interested me. Finally, I came up with an optimal route so that I could visit all the stands by the shortest route.
Do you perhaps know these considerations from visiting your own trade fair?
In such situations, I kept thinking about how nice it would be if there were a mobile application that could take over the navigation in closed rooms/buildings. The question always remained, why are there no such apps for indoor navigation? Is the implementation of these functionalities extremely complex, expensive or impossible?
I shared my thoughts on indoor navigation with my colleague Jan Winter, and we started researching how to implement a navigation app with an interactive map for any event.
Bluetooth Beacon Indoor Navigation Challenges
When creating a navigation app with an interactive map for an event, there are two basic problems to be solved: the implementation of navigation and map digitization.
Navigation
The navigation is important for determining your own position, for planning the route and for navigating yourself. The “classic” version of the navigation is based on global navigation satellite systems (GNSS) such as GPS, GLONASS, Galileo or Beidou and works flawlessly in open spaces outside of buildings.
The GNSS signal is present partially or not at all within a building, so that navigation is very imprecise or not possible at all. Other location technologies for automatic position determination are used here.
Since most of the trade fairs and exhibitions take place in closed rooms and indoor navigation itself offers a very wide range of applications, we have decided to concentrate on this type of technology.
As already mentioned, navigation within a building is referred to as indoor navigation or indoor location tracking. WLAN or Bluetooth technologies are mostly used for position determination. In both cases, the current position can be calculated on the basis of signal strengths and coordinates of different signal sources such as WLAN routers or Bluetooth beacons (BLE beacon) and the distances to them.
After further research and weighing up the advantages and disadvantages, we decided on the Bluetooth technology. We use Bluetooth beacons and iBeacon navigation as signal sources. These are Bluetooth devices with low energy consumption (Bluetooth Low Energy, abbreviated BLE).
The indoor location beacon can send their identification data to other nearby electronic devices. In our case, these are smartphones. The identification data differ depending on the protocol, i.e. Eddystone or iBeacon.
Bluetooth Beacon Indoor Navigation Has The Following Advantages Over WLAN:
• Low energy consumption: Bluetooth beacon positioning does not have to be connected to the mains. The battery life is on average two to five years.
• Lower acquisition costs: A low power Bluetooth beacon costs around 20 to 30 euros.
• Installation flexibility: thanks to small dimensions and different shapes, the Bluetooth low energy beacon can be placed anywhere and usually remain undetected.
Map Conversion
We wanted the card to respond to user interactions. When tapping on a specific location, the app must clearly identify this location. This enables them to display a description or additional information about a stand or room, for example. In addition, it should be possible to mark a specific location on the map, for example, to show the current position of the user.
It follows from the use cases described above that, in addition to the image of the site plan, metadata are required which contain the coordinates, sizes, and shapes of map elements.
The search for software that can analyze and evaluate the image of a map or a site plan has yielded nothing.
We, therefore, decided to find a program instead, with which you can manually mark and name objects on a map and export the resulting data in an open data format. We noticed LibreCAD.
This free CAD software met all of our requirements and can export the project data as an SVG file.
Prototype Beacon Location Tracking
In order to implement our idea and at the same time undertake a field experiment, we decided to develop a prototype mobile navigation app for our Leipzig office.
It is a single-screen application for Android and iOS that has the following features:
Zoom: The user can enlarge and reduce the map.
Room description: When you tap on an office room or area, the corresponding description is displayed in a new screen.
Filter function: When certain filter categories are activated in the filter popover, the associated rooms and areas are marked on the map.
Positioning: When you tap the location button, the navigation app shows the office space or area in which the user is currently located.
In order to enable the location to be determined, we have installed one or two Bluetooth beacons in each office room, depending on its size.
The iBeacon protocol is used for communication between the beacon and smartphone, as it is compatible with both iOS and Android.
Working of Indoor Location Beacon
To assign a Bluetooth beacon to a specific room, we use the identification data of the iBeacon protocol, which includes the UUID, major and minor values of the device. The UUID indicates that it belongs to a certain super-group (for example a certain building).
The major value assigns the beacon to a subgroup, for example, a floor of the building, and the minor value identifies the beacon itself and thus, for example, a specific room.
We have developed a fast and user-friendly method for digitizing the map: You load the map image in LibreCAD, mark the outline of the individual office rooms and areas, assign an ID to each outline and export the result as an SVG file.
We manually wrote the names and descriptions of the rooms and the data for the filter functions into a JSON file and inserted them into the Android and iOS projects together with the image of the map and the associated SVG file.
When it starts, the app reads in all metadata and uses it to build an interactive office card.
Conclusion
Bluetooth beacon Indoor navigation system is a promising and versatile concept. It can be used to determine your own position, to identify exhibition stands, areas in a museum, floors, and rooms of a building and much more.
Further functions are also possible. For example, you could use your smartphone to mute the smartphone when entering a reading room or trigger location-specific actions in general.
Bluetooth beacons are very flexible. They are easy to install and configure, can be placed anywhere and do not require a central power supply.