Location – Page 10 – BeaconZone Blog

Beacons to Detect Proximity

Beacons can be used to detect if things or people are in a zone by either putting beacons on the moving things or having the beacons static in a zone.

For the beacons on things/people approach, a gateway or other scanning device looks for beacons in the vicinity and triggers actions. For the static beacons case, an app on peoples’ phone can detect beacon(s) in a zone and trigger actions.

We have some new beacons in stock that now provide a third way of detecting proximity. They use IR and PIR to detect the proximity of any item coming within range. For IR that’s <50cm and for PIR < 5m. These beacons transmit the current state via Bluetooth that can be picked up by an app or gateway.

iBS02IR

iBS02PIR

It’s expected these beacons will be more suitable for IoT and Industrial scenarios.

How Does Using Beacons for Tracking Compare with the Use of RFID?

The main difference between beacons and RFID is the range. RFID only works up to 1m while beacons typically reach 50m to 100m, even more for specialist beacons. It’s also possible to get an indication of distance to the beacon whereas with RFID it’s just ‘seen’ or ‘not seen’.

RFID tags are less expensive than beacons. However, as the range of beacons is much larger, fewer readers are required thus compensating for the extra cost. It’s also possible to totally cover a much larger area.

New Report on The Proximity & Location Industry

Proximity.directory has a new report on the State Of The Proximity & Location Industry. It’s great to see proximity.directory reports moving beyond retail marketing into asset tracking.

The report gives a great overview of how asset tracking works, the benefits, provides some case studies and lots of charts.

“Hospitals can save hundreds of
thousands dollars a year with an
immediate ROI of 275%”

Download the report.

Research Paper on Using Bluetooth for Indoor Locating

There’s a paper by Mariusz Kaczmarek, Jacek Ruminski and Adam Bujnowski of Gdansk University of Technology on the Accuracy analysis of the RSSI BLE SensorTag signal for indoor localization purposes (pdf).

They studied the radio signal from multiple Texas Instruments SensorTag CC2650 devices in order to determine if it could be used to determine location.

They concluded:

“Given the large number of factors governing the received RSSI, calibration is unlikely to be able to compensate for all of
them, leading us to conclude that there is an inherent limit to the accuracy of a BLE positioning system especially when multiple devices are used.”

They suggest:

…that instead of using a single RSSI measurement to estimate distance, try using the average or median value of N measurements collected on the same spot (at least N>20) so that you can reduce the effect of small scale fading.

Beacons and Lone Workers

There are types of working where workers work alone without close or direct supervision. Employers have a legal duty of care to monitor such employees so that they can detect accidents, illness and, in some cases, an attack.

There are some rudimentary systems in place, particularly on sites such as airports, that use short range (1cm) RFID tags that workers have to periodically ‘check in’ to. With beacons, workers don’t have to check in and much of this is now automated. It also works at much larger ranges up to 300m.

Our BeaconRTLS system maps lone workers. Alerts can be created that show when people haven’t changed zone for a configurable amount of time. It’s also possible to trigger alerts when people enter or leave zones or when they press an ’emergency’ button on the beacon.

What’s more, the system can be used to map assets as well as people and when used with sensor beacons can detect and alert based on environmental factors such as temperature, humidity or whether doors are open or closed.

Bluetooth Beacons in Factories, IoT and Industry 4.0

McKinsey has a useful chart where they assess the potential impact of the IoT by segment:

It can be seen that ‘Factory’ has the greatest potential. This links with ‘Industry 4.0‘, the current trend for more automation and data exchange in manufacturing with the aim of significantly improving efficiency. But what does this mean in practice and what are challenges? Can these be solved with Bluetooth beacons?

We have learnt that while just about every industry client has different needs, all solutions involve context and location. Context is sensing, while location is where the sensing occurs.

Requirements we have experienced range from being able to pick up documents for particular machinery through to actual sensing such as detecting vibration is within (safety) bounds for ‘aggressive’ equipment. We have also seen the requirement for matching workers with workstations and jobs as well as the tracking of workers, tools, pallets, parts and fabrications. There’s also the need for real-time overviews for short term safety and efficiency management, the same longer term data also being used for process improvement and planning.

So why beacons?

Low power. Sensors need to have a long life because replacing them or their batteries requires human effort and they are sometimes placed in normally inaccessible and dangerous areas. Beacons are ideal for this because some have up to 5+ years battery life and others can be permanently powered.
Sensing. Various off the shelf sensor beacons are available. Custom variants are possible to sense industry specific metrics.
Connectivity. Several gateways are available to connect to WiFi. Alternatively, it’s possible to use smartphones or small single board computers as gateways. There’s a trend for ‘Fog’ or ‘Edge’ gateways that only send pertinent data on to the cloud and can provide direct alerts quicker than being dependent on the latency of the cloud.
Cloud management. Software such as our BeaconRTLS platform allows for the management and visualisation of sensors.
Security. Beacon devices are password protected and the gateway to cloud communication is protected using standard Internet protocols.
IoT needs to be made easy. This is BeaconZone’s role. As we mentioned, with the IoT every client has different needs. We bring together ready-made hardware and software components so that they can be dovetailed to create solutions.

Read about using Beacons in Industry and the 4th Industrial Revolution (4IR)

Read about BluetoothLocationEngine™

Cow Positioning with iBeacon Technology

There’s a video at YouTube on the installation of Raspberry Pi based beacon detectors in a cow shed to detect the position of cows.

Beacon detectors

Beacon on a cow

Beacons can, in fact, do a lot more than just determine location. For example, it’s possible to track extra things such as temperature, humidity and unexpected movement. In the cow shed case, hall effect beacon sensors can be put on gates to alert when gates are open/closed when they shouldn’t be. The location data can be used to provide geofencing to alert when things, people or animals enter or leave specific areas.

Making Sense of Indoor Location

There’s a recent research paper on Indexing for Moving Objects in Multi-Floor Indoor Spaces That Supports Complex Semantic Queries. It says humans spend 87% of their time in indoor spaces such as private residences and office buildings and it’s becoming more important to be able to derive meaning from indoor location.

The paper explains how outdoor moving object management technology, which is very mature, cannot be applied to indoor spaces. Instead you need software that not only understands floors but also multi-floors and inter-floor (elevators and stairs) cells. The paper describes an index that can store indoor moving objects in multi-floor indoor spaces that can support 3D spatial queries.

Beacon Locating Accuracy

There’s a useful article by Steffen von Bünau of Kontakt on Real Time Location Systems (RTLS). Steffen says:

“Accuracy is an expensive vanity metric unless it is necessary to get the job done.”

Most scenarios don’t usually need very accurate positioning and creating unnecessarily accurate systems is expensive. Steffen doesn’t say why they are expensive but one of the article’s comments provides an answer. Ultra wideband based RTLS is expensive compared to Bluetooth LE.

Also, accurate systems tend to need calibration that’s time consuming and costly in human resource. Calibration implies tuning to a particular physical and wireless environment. If the environment changes then so might the calibration.

The required accuracy of a RTLS should be derived from the business requirements.

Improving on Beacon Immediate, Near and Far

We recently highlighted an article on Beacon Trajectory Smoothing. Faheem Zafari, Ioannis Papapanagiotou, Michael Devetsikiotis and Thomas Hacker have a new paper on An iBeacon based Proximity and Indoor Localization System (pdf) that also uses filtering.

They use a Server-Side Running Average (SRA) and Server-Side Kalman Filter (SKF) to improve the proximity detection accuracy compared to Apple’s immediate, near and far indicators.

The researchers found:

The current (Apple) approach achieved a proximity detection accuracy of 65.83% and 67.5% in environment 1 and environment 2 respectively. SRA achieved 92.5% and 96.6% proximity detection accuracy which is 26.7% and 29.1% improvement over the current approach in environment 1 and 2 respectively

What’s interesting here is that the researchers have quantified the accuracy of Apple’s implementation in two scenarios. The accuracy isn’t that good and as the researchers have shown, can be improved upon significantly.