Arduino project based on the LilyGO-T-SIM7000G board with some additional sensors added. The tracker sends location info from the device to a MQTT broker via LTE connection.

• LilyGO-T-SIM7000G
• Added reed sensor between pin GPIO0 and GND, reed sensor 10mm
• added SENSOLUTE MVS0409.02 vibration sensor between pins GPTIO32 and GND: Datasheet in doc-folder
• External charger connector SP11 connected to VIN and GND

A 3D-printable case can be found from Printables.com: LilyGO T-SIM7000G case

• Arduino IDE: version v2.3.0 or above
  • Version v2.3.0 or above from official Arduino website
• ESP32 bord configurations
  • Add ESP32 boards to Arduino IDE board manager by adding link to additional board configurations.
    • Add https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json to File --> Preferences --> additional boards manager URLs field in the Arduino IDE
  • Install ESP32 boards from the bord manager
    • Go to Tools -> Board -> Boards Manager and seach and install "esp32" by Espressif Systems
• External libraries, this project relies on two external libraries that can be installed from the Arduino IDE library manager: Sketch -> Include Library -> Manage Libraries, search and install the following
  • TinyGSM (v0.11.7)by Volodymyr Shymanskyy
  • PubSubClient(v2.8) by Nick O'Leary

• Edit configuration file
• Change boad setting from Arduino IDE by going Tools -> Board and select ESP32 Dev Module
• Compile the software!

Edit the config.h file

#define PROJECT_NAME "tracker" // Project name, is used in MQTT topic
#define BROKER_HOST "" // IP or address of the MQTT-broker
#define BROKER_PORT 1883 // MQTT-broker port, MQTT default port is 1883
#define BROKER_USER "" // MQTT-broker username
#define BROKER_PASSWD "" // MQTT-broker password

#define GSM_PIN "" // PIN-code of the SIM-card, if no PIN-code leave empty ""
#define APN "iot.1nce.net" // Carrier APN for internet, 1NCE: iot.1nce.net, Elisa/Telia/DNA: internet
#define GPRS_USER "" // Username for the cellular internet connection
#define GPRS_PASS "" // Password for the cellular internet connection

#define HTTP_OTA_URL "" // Address to the the OTA-update file

The tracker communicates using the MQTT protocol, which is a publish/subscribe -type protocol.

The tracker also uses HTTP for OTA-update downloading.

Tracker ID id an unique 7-numbered identifier for the tracker. It is made from the cellular modems IMEI-number.

When the tracker connects to the tracker it updates the connected topic to 1. If the tracker connects to the broker for the first time after boot, it sends the installed software version.

The tracker periodically sends a status message that contains the battery state of charge(SOC), cellular signal strength and charging status. These values are sent as a comma separated string.

Example message: 55,90,0

• Battery SOC 55%
• Cellular signal strength 90%
• Charger not connected

Location update contains the following fields: Latitude, Longitude, Speed, Altitude, Accuracy, Course, Visible satellites, Used satellites Latitude and longitude are degrees and in decimal format. The data is comma separated in the message.

Example message: 60.169900,24.938400,0.000000,14.500000,1.800000,194,23,4

• Latitude: 60.169900 deg
• Longitude: 24.938400 deg
• Speed: 0.000000 km/h
• Altitude: 14.500000 m
• Accuracy: 1.800000 m
• Course: 194 deg
• 23 visible satellites
• 4 satellites used

The device listens to the MQTT broker for settings which in this case is the system mode and periodic track interval. The periodic track interval is sent always but it will be applied only when the periodic track -mode is activated. The setting unit is seconds. The tracker has the following working modes:

• 0: Hibernate, wake up only with magnet
• 1: Sleep, Go online every 60 minutes, also wake up by magnet
• 2: Track, Send device position if device sensed movement
• 3: OTA, update device firmware via wifi(Entered by giving OTA wifi details)
• 4: Idle, stay connected to the MQTT Broker
• 5: Periodic track, send position on set time interval

The repository also includes an updater utility to help with updating multiple devices. The updater is located in the util-folder. In order to use the updater, the MQTT-broker details need to be set to the config.ini file.