BLE Beacon Scanner

STEM workshop reading Bluetooth beacons

Overview of aims

Bluetooth Low Engergy (BLE) beacons are becoming more well known with the likes of Apple's iBeacon and Google's Eddystone (Physical Web).

The aim is to take this technology and show that it is accessible to students and the maker community. By showing it is accessible, the hope is that people then take some of the ideas and use them for positive and creative endeavours.

The hope is that this library/project will evolve as lessons are learnt about how to make this technology accessible to the target audience.

The target audience is someone that has some basic understanding and experience of programming with Python, but may not have done anything with Bluetooth. They are unlikely to have experience with bytes, little-endian etc.

To assist with the accessibility goal, hardware will be targeted that is likely to be available (and understood) by schools, code club etc.

Some assumptions being made at this time about the hardware:

• The Raspberry Pi's (RPi) will do the scanning for beacons
• The RPi's will be mains powered and so need to be static
• The beacons will be battery powered and could move if required.
• The beacons will be based on standards that are documented publicly

To allow for ease of adoption:

• Require minimal steps to install and run first example
• The workshop code will allow for it to be extendable so students could explore their own projects ideas based on what they have learnt
• Use a language familiar to schools. (This seems to be Python).

Quickstart

Install Bluetooth software on Raspberry Pi

Best practice would be to have setup instructions that don't include the use of sudo, however a decision has been taken to prioritize convenience rather than security. In the full documentation other options should be discussed.

To install the library directly from GitHub:

sudo pip install git+https://github.com/ukBaz/ble_beacon

Scanning for beacons

This example will print the URL being broadcast by an Eddystone-URL beacon

from scanner import protocols, hci_socket

for pkt in hci_socket.run():
    ad = protocols.AdvertEventHandler(pkt)
    if ad.eddystone_url:
        print(f'\tEddystone-URL: {ad.eddystone_url.url} @ {ad.rssi}dB')

If you save the above as find_url_beacon.py then to run it would be:

sudo python find_url beacon.py

An example expected output would be:

$ sudo python3 examples/beacon_finder.py 
        Eddystone-URL: https://microbit.org/ @ -39dB
        Eddystone-URL: https://microbit.org/ @ -48dB

Creating a beacon

Using your phone

For testing, you can use an Android or iOS device to simulate a beacon.

Android:

• https://play.google.com/store/apps/details?id=net.alea.beaconsimulator
• https://play.google.com/store/apps/details?id=com.davidgyoungtech.beaconscanner

iOS:

• ??

Using a BBC micro:bit

One of the easier ways to create a beacon is using Makecode on the BBC micro:bit.

The code inside the forever loop is just to give visual feedback that there is something running on the device.

You will also need to swap the Radio blocks for the Bluetooth blocks which can be done by clicking on th cog in the top-right corner (not shown) and selecting Extensions -> Bluetooth