Functional Description

General Overview and Information*

The miro TrackIt device is a powerful and flexible GNSS tracking device that integrates a multi-standard GPS scanner and passive Wi-Fi MAC address scanner with Bluetooth 5.2 connectivity and sensors such as accelerometer into one compact device. The IP65-rated housing with different mounting options prepares the device for operation in a harsh industrial environment.

Device Initialization and Joining

flowchart LR
    A(Firmware and <br/>Almanac Update) --> B(Join LoRaWAN<br/>Network)
    B -->  C(Track Assets)

This overview shows the general the procedure at start-up. In the first step indicated by a short tone, the device starts to advertise BLE for 30s (update window) to allow for firmware and almanac updates via App.

After this has passed, the device starts to join to the LoRaWAN network, playing a long tone on each join trial. If a network connection is established, the device will play a melody and start to track the asset.

If a join trial fails, the device will retry the join with a join back-off strategy. The device will start to retry at
different intervals. This approach is split into 5 possible cases. In each case, the device will retry to join, according to Retry Timeout. If a connection could not be established during the specific Case Timeout time, the device will change the mode to the next higher one, except the last mode 5.

flowchart LR
    A(Mode 1) --> B(Mode 2)
    B -->  C(Mode 3)
    C --> D(Mode 4)
    D --> E(Mode 5)
    E --> E

Case	Retry Timeout	Case Timeout*
Mode 1	1 minute	15 minutes
Mode 2	15 minute	45 mintues
Mode 3	Hour	24 hours
Mode 4	Day	7 days
Mode 5	Week	-

Important

If the device reaches the case Mode 5, it will stay in this case until a LoRawan connection is established. Hence, there are no further interval or timeout updates. The device will weekly try to join the network.

Asset Tracking

The device will track the location periodically after a steady time. If the device is set in motion, it will use a shorter movement time to track the asset periodically. If the motion stops, the device will use the steady time again. In between those periodically tracking intervals, the device will enter the sleep mode which is the lowest possible power mode.

stateDiagram-v2
    s1: Sleep Mode
    s2: Moving
    s3: Track fast
    s4: Track slow
    s1 --> s2: Movemnt
    s2 --> s3: Movement Timer 
    s2 --> s1: Static
    s3 --> s2
    s4 --> s1
    s1 --> s4: Steady Timer

Important

All mentioned device tracking time periods are adjustable. Consider the <>.

The device tracks the location with Wi-Fi and GNSS scans and sends the collected data through a gateway to a backend sever. The location is generated by GNSS data and if not available/valid then Wi-Fi data. The server displays the location data on the Semtech LoRa Cloud website.

Device Reset

To reset the device, a pattern detection algorithm is implemented. The pattern consists of a sequence of device positions. Reset the device using the following procedure:

To start the pattern matching algorithm

remove device from asset surface
hold it steady for 30 seconds
shake the device until it beeps

Now follow this sequence to trigger a device reset:

turn right
turn up-side down
turn left

Note

The device will beep after each matched position

The video clip explains the reset procedure of the device:

Device Configurations and Updates

Device Parameters

All device settings are fully configurable over the Semtech LoRa Cloud website. Read more information about the uplink and downlink payload structure here.

Note

The device must be joined to the LoRaWAN network in order to change the device settings.

Firmware Update

In order to do a firmware update, the device must be resetted. After a successful reset, the device will enter a 30s interval where a firmware update is possible. During this time period, a connection with the EFR Connect App has to be established in order to execute the update.

Compatible mobile devcies

Apple Devices	Android Devices
Version 2.5.0	Version 2.5.0

Warning

The EFR Connect App version must be compatible with the version from the table for successful firmware update.

Firmware images can be downloaded in the download section

Update Procedure

Download the correct firmware image and ppen the EFR Connect App. Select "Browser"

Select "Start Scanning"

Select "miro_tracker" and press "Connect"

Select the 3 stacked points in the upper right corner

Select "OTA DFU"

Click on "Select application .gbl file" ** Chose your downloaded miromico firmware file . Select "Reliability" or "Speed" . Press on "OTA" in order to execute the firmware update

If the update is successfully executed, press the "END" button to close the connection

Close the application

Almanac Update

still in progress, more information will follow