Combining Indoor Navigation and Asset Tracking

Asset Tracking solutions have become essential not only for outdoor spaces, but also for indoor working environments, e.g. for locating goods in warehouses. Combining Indoor Navigation and Asset Tracking, however, allows for far more complex use cases. For instance, locating a security guard via mobile device and assigning them to an incident in their vicinity.

The resulting solutions have found their way into industries such as healthcare, transport and security a.o., where they contribute to an increased workflow efficiency, time and cost savings as well as customer satisfaction.

The technology behind it varies, depending on the provider, and ranges from RFID (Radio Frequency Identification), UWB (Ultra Wideband) and NFC (Near Field Communication) and even WiFi. However, all of these show significant drawbacks in different fields.

Whereas RFID based Asset Tracking requires dedicated reading devices, using WiFi exceeds regular power consumption levels, NFC only delivers acceptable results in low range settings and UWB is comparably expensive. The only approach that is simple to roll out and equally energy and cost efficient is one using Bluetooth Low Energy Beacons.

Therefore, indoo.rs uses BLE Beacons to enable accurate Indoor Navigation, which simultaneously serves as the setup for Indoor Asset Tracking. Now, what role does NetFLIPs play in all of this?

NetFLIPs™ – the solution

The word NetFLIPs consists of network combined with FLIP (“Flexible Indoor Position estimator” designed for fingerprint based positioning systems). NetFLIPs is our proposed Asset Tracking and Positioning system. How it works is described below.

Beacons are linked to physical assets and are therefore mobile. The receiving devices are static. They scan nearby Beacon signals and obtain their ID, RSSI and reception time, forwarding this data to its dedicated receiver concentrator.

Depending on the currentness-requirements and scalability of the system, this data is locally buffered for a defined period of time and transmitted to the concentrator afterwards, rather than transmitting each scan. This way the number of receivers for one concentrator can be increased and the power consumption for the involved devices reduced.

The receiver concentrator collects the data of its connected receiving devices and normalizes the individual receivers’ scan-times to the time base of the concentrator. It is connected to the NetFLIPs server. All concentrators have to be clock-synchronized by Network Time Protocol (NTP), for example.

 

The NetFLIPs server processes the incoming data of the receiver concentrators. Since the receiver concentrators are clock-synchronized, the NetFLIPs server is time-independent, to also allow replaying archived concentrator data at arbitrary speed. As a fingerprinting approach is used, the radio-map of the site is required, which can be obtained via indoo.rs cloud.

 

FLIP is employed to estimate the position of the asset-Beacons based on the radio map and the collected recordings. The resulting Beacon trajectories can be saved and accessed via a REST-interface for monitoring and further analysis.

The indoo.rs cloud is the source for the radio-map of the site. Before the NetFLIPs system can be used, the radio map for the Asset Tracking system has to be obtained. The procedure for that would be different from the standard procedure for fixed Beacons and mobile receivers. However, since the receiving devices are able to work in Beacon mode, the radio map for positioning can be obtained by the standard procedure – capture the signals by walking naturally through the building and use indoo.rs SLAM Engine™ to get the radio map.

 

This radio map can be used for user positioning and, additionally, Asset Tracking due to antenna reciprocity and FLIP, which can also handle inherent device dependency challenges.  An optional monitoring and analyzing unit requests the NetFLIPs server to process Location Based Services, visualize the current Beacon positions or trajectories or use them for logistics optimization purposes.

 

NetFLIPs use cases:

  • Routing users to assets
  • Monitoring and analysing assets’ trajectories

 

Benefits of NetFLIPs in comparison to other systems:

  • Simultaneous mobile positioning & asset tracking
  • Quick and easy system setup using indoo.rs tools
  • Low infrastructure hardware requirements
  • Cheap, off-the-shelf hardware available

 

If you are interested in NetFLIPs, please download the paper written by Reinhard Müllner and Thomas Burgess: