ESP32 iBeacon Indoor Positioning System (IPS)

This is a small demo application showing how to use ESP32 modules as anchors/stations to do indoor positioning of iBeacon tags (tagged people, dogs, cats and objects) with trilateration.

A minimum of three ESP32 modules are needed to run the application, since this is required to do the trilateration.

Getting Started

Installation

Mosquitto MQTT Broker (server)

MacOS using homebrew

$ brew install mosquitto

Ubuntu 16.04 using apt

$ sudo apt install mosquitto

Other Platforms

• For other platforms e.g. Windows, check out https://mosquitto.org/download/

NPM for running the web dashboard

MacOS using homebrew

$ brew install npm

Ubuntu 16.04 using apt

$ sudo apt install npm

Windows:

You may try out the guide here (untested): https://www.techomoro.com/how-to-install-and-setup-a-react-app-on-windows-10/

Note! You may need to install some extra libraries via NPM e.g. chalk. You will see an error if so, when you run the dashboard.

$ npm install chalk

ESP32 IDE and libraries

You can either use the Arduino IDE or PlatformIO for Visual Studio Code to upload the code to the ESP32.

If you are not familiar with PlatformIO and Visual Studio Code (vscode), then I can highly recommend you to check it out. vscode is a very nice IDE for programming whatever, and PlatformIO is a nice way to program Arduino's and ESP32 in general with good code completion.

Arduino BLE and MQTT libraries

You need the following two libraries, both can be installed from the Arduino IDE Library Manager or PlatformIO:

• PubSubClient
• ESP32 BLE Arduino

Note! See Troubleshooting section below in regards to PubSubClient and packet size (MQTT_MAX_PACKET_SIZE). There may be problems in sending too much data if a station finds too many beacons. Check the serial console for an ESP32 and make sure that it prints out PUB Result: 1. If it prints PUB Result: 0 there may be a problem transmitting the json data to the MQTT server. This can be fixed by changing MQTT_MAX_PACKET_SIZE in the PubSubClient library.

Setup and running

Mosquitto MQTT Broker (server)

Edit the file mosquitto-demo.conf. Set the path to acl files, like:

acl_file /home/w3/Downloads/iBeacon-indoor-positioning-demo/mosquitto_acl.config
password_file /home/w3/Downloads/iBeacon-indoor-positioning-demo/mosquitto_pw.config

Start mosquitto with the following command:

$ mosquitto -v -c ./mosquitto-demo.conf

MQTT users are "station" and "dashboard", and all passwords are "bledemo".

Note! :On MacOS mosquitto may not be a recognized command after installation. You will then need to add mosquitto to PATH, like so and restart your terminal:

$ sudo echo 'export PATH="/usr/local/sbin:$PATH"' >> ~/.bash_profile

ESP32 stations

Edit the file credentials.h and change wifi ssid and password, and also change mqttServer to the IP of the computer running the mosquitto server. Upload the Arduino sketch ESP32_station.ino to your ESP32.

Place the ESP32 modules around the area where you want to do positioning, preferably 10-15 meters appart and also in wifi range.

ESP32 modules will work as iBeacon monitoring stations, reporting all found bluetooth beacons to the MQTT topic, with their MAC address and RSSI.

Web dashboard

The dashboard is a simple React app, connecting to the mosquitto MQTT server and showing each beacon on screen.

To run the dashboard from a terminal go to the dashboard folder and run npm start

$ cd dashboard/
$ npm start

A browser window will automatically open the dashboard react app, else go to http://localhost:3000/

Stations and beacons will show up on the map when at least three ESP32 stations are connected.

Troubleshooting

PubSubClient MQTT_MAX_PACKET_SIZE

The PubSubClient library may have problems sending big packages to the MQTT server e.g. when ESP32 finds many beacons. In the Arduino sketch you can set #define MQTT_MAX_PACKET_SIZE to e.g. 2048, but I have experienced that it may not work anyway. Instead I downloaded the PubSubClient library and added it to my PlatformIO project. Here I could change the code of PubSubClient.h around line 26 to #define MQTT_MAX_PACKET_SIZE 2048.

I may add the PlatformIO project here later for easier setup.

TODO

• improve accuracy (average value, faster beacons, sync stations)
• add beacon MAC whitelist to sidebar
• add server settings to sidebar
• add properties to beacon icons
• connect to iTAG's
• ... what else?

Acknowledgement

The initial code is forked and derived from the example by @jarkko-hautakorpi https://github.com/jarkko-hautakorpi/iBeacon-indoor-positioning-demo.