iBeacon, Eddystone, Bluetooth, IoT sensor beacons, apps, platforms
We have a new small, thin, wearable beacon the K21 in stock. It advertises iBeacon, Eddystone and sensor advertising including the battery level, temperature and acceleration (x, y, z).
This beacon can also be used to detect motion and the button press.
Researchers from the The Hong Kong Polytechnic University have a new paper on Performance Evaluation of iBeacon Deployment for Location-Based Services in Physical Learning Spaces (pdf) that tests environmental and deployment factors, indoors and outdoors, related to using ibeacons for locating. It provides recommendations for iBeacon deployment in terms of location, density, transmission interval, fingerprint space interval and collection time.
The paper provides a great introduction to positioning using beacon received signal strength (RSSI). It describes trilateration and fingerprinting methods for determining location.
Key insights are:
The paper mentions that beacon UUID, major and minor are used to uniquely identify beacons. While this is true in the context of detecting using apps, most locating systems use gateways. Gateways use the Bluetooth MAC address to uniquely identify beacons and the advertising type, iBeacon, Eddystone or other, is irrelevant. Using gateways as receivers is also a solution to the problem of variability in receiving capability across smartphones.
The study only considered one beacon type and two receiving smartphones. At Beaconzone, we recommend experimenting with the actual hardware in the actual environment as, being wireless radio, optimum settings and can vary considerably.
Read about Using Beacons, iBeacons for Real-time Locating Systems (RTLS)
A growing number of checkin/checkout systems are using iBeacons. Having an iBeacon at an entrance to a building allows employees to be automatically clocked in and out. It provides confirmation that a worker did actually arrive at a certain place that day.
PeopleHR is one such solution that has information and a blog post on how to set up tap in and out using beacons.
Checkin/out systems use the iBeacon type of beacon because it can be detected on iOS (and Android) even when the app isn’t in foreground.
The Hong Kong Multimedia Technology Research Center (MTREC) has an interesting project that implements a dementia anti-wandering system using iBeacons.
A paper (pdf) explains how it uses a novel multi-hop system to track targets using mobile sensors. The multi-hop approach extends the sensing area and reduces the deployment cost.
The system uses a particle filter which analyses the temporal and spatial information of the targets to achieve 4.37m and 9.46m tracking error in a campus and a shopping mall respectively.
Martin Woolley of the Bluetooth SIG was a recent speaker at Droidcon EMEA where he spoke about Advanced Bluetooth for Android Developers (slides).
Martin covered scanning, GATT, how to maximise data rates, speed vs reliability and using different PHY for enhanced range or data rates. The second part of the talk covers Bluetooth Mesh and proxy nodes.
One thing not mentioned in the slides, to be careful of, is that connection via a proxy node is relatively slow because it’s limited by the GATT connection. Proxy nodes are good for controlling (sending small amounts of data into) a Bluetooth Mesh but poor if you want to use the connected Android device as a gateway for all outgoing data.
Martin also has a blog where you can also learn about his past talks and he will be part of the new Bluetooth Developer Meetup.
There’s a new article on MyLondon on How this Putney hospital is using smart technology to track down life-saving equipment. It explains how Putney hospital is using sensors to track equipment, such as ECG machines, to make them easier to find. They are also monitoring the temperatures of fridges and the occupancy of rooms.
The time saving is incredible… there are thousands of more things the hospital would want to track in the future
Toby Roberts, Putney Hospital Associate Director of Information
At BeaconZone we have customers using beacons to track wheelchairs, porters carrying medicines and the location of vulnerable Alzheimer’s patients.
We have found the main problem with introducing new technology into hospitals is lack of funding. Anything outside purchasing for the frontline is de-prioritised. Health providers tend to have have blinkered priorities that work against efficiency and cost savings.
If you think about having three key nurses and a couple of health care assistants running around the hospital for half an hour to find a piece of equipment, even if you just add up their hourly rate, let alone the increase in service quality, it’s really quite an easy equation to justify
Toby Roberts, Putney Hospital Associate Director of Information
There’s a new (virtual) Bluetooth Developer Meetup group.
Developers will share their knowledge and tell their stories of working with everybody’s favourite low power wireless communication technology
The first event will be on 15th October 2020 at 17:30 UK time (UTC+1) and will include the following speakers:
Beacons send most of the time periodically advertising the same data. For setup, apps usually connect to them to set settings such as the advertising period, unique id and power level. The connection is performed using standard Bluetooth GATT.
Bluetooth LE devices connect to others via GATT. Devices such as fitness trackers and our social distancing beacons are regularly connected to, to download data. It’s also common to connect to sensor beacons to extract sensor data.
GATT is usually used via compiled code and it can be time consuming to test GATT devices and/or subsequently use the GATT interface in a flexible way. Should you need to do this, take a look at Bleak GATT client software capable of connecting to Bluetooth LE devices acting as GATT servers. It provides an asynchronous, cross-platform (Windows 10, Linux, Mac) Python API to connect and communicate with Bluetooth devices.
There’s a new video of the Nordic Semiconductor webinar on Everything you need to know about Bluetooth LE advertising. It covers the basics of Bluetooth LE including advertising and data formats. It explains how to use the nRF Connect SDK API and provides a demo. It also shows how to use nRF Sniffer to examine Bluetooth LE data packets.
The presentation and Q&A are also available.
The video mentions advertising extensions. These are only in Bluetooth 5. Most current devices only support Bluetooth 4.2 legacy advertising. Growth in numbers Bluetooth 5 devices has been limited due to the non-compatibility with the majority of smartphones. It’s for this reason that devices that are Bluetooth 5 usually communicate using, backward compatible, legacy advertising. Extended advertising is also an optional feature of Bluetooth 5.
On iOS 14, Apple has changed the permissions required for iBeacon region ranging and monitoring. There’s a new Precise Location permission that needs to be set to ON for the app to continue to work. Apps that granted location permissions prior to iOS 14 default to Precise Location ON after upgrading so as not to break old code.
Apps should now detect if Precise Location is enabled. Apple has unfortunately deprecated the class function authorizationStatus(). The best way of determining whether you can detect iBeacons is to examine the location accuracy.
There’s an explanation on Medium by Nick Patrick and there’s a post on StackOverflow with an example how to detect whether Precise Location is on by examining the location accuracy.
