Fluke Process Instruments

Using the MQTT Data

There are five different topics available for selection: ‘Counts’, ‘Status’, ‘Targets’, ‘Live counts’, and ‘Device Info’. The ‘Targets’ topic is only available on Vector Analytic devices - not Vector Counts.

There must be an application that connects to the MQTT broker and subscribes to a data topic to receive the data provided. This is something that you will most likely have to create yourself, based on your own count data usage requirements, and the topics selected.

There are many free websites that can provide an MQTT broker which can be used for test purposes, if required.

We have some code examples on how to integrate with MQTT and also the REST API and the HTTP Post functionality, stored online at the GitHub repository. Go to: https://github.com/IrisysUK

Retain State

Some MQTT Brokers will cause additional data processing costs of MQTT messages when the Retain State is enabled.

In these cases it can be disabled if required, in the settings on device for that particular topic. See here.

MQTT Message Format

Counts Topic

Whenever a count register value changes, an event message is queued containing the register name, the change in value and the timestamp. This will be sent out along with any other pending messages on the next publication interval (configAWured in RIFT as the “period” value). An example of the message format of a ‘Counts’ topic is as follows:

[{      
      "register": "MainEntranceIn",
      "value": 1,
      "t": "2019-02-91T12:30:00+0000"
}, {      
      "register": "MainEntranceOut",
      "value": 1,
      "t": "2019-02-91T12:30:12+0000" 
}, {
      "register": "MainEntranceIn",
      "value": 1,
      "t": "2019-02-91T12:30:14+0000" 
}]

In the example above there have been count increments on two registers- two on the one named as “MainEntranceIn” and one on the register named as “MainEntranceOut”. The timestamps indicate the time of each event occurrence.

If no count events occur in the interval, an empty array will be sent out as below:

[]

Status Topic

Status event messages are published on connection and disconnection from the broker.

Connection Message

This is of the following format:

{“status”: “connected”}

Disconnection Message

This is sent up to the broker on connection as its “Last Will and Testament”. The broker will then push this out to subscribers in the event of the device’s disconnection. This is of the following format:

{“status”: “disconnected”}

Because it is the broker that pushes this out when a device disconnects, any ungraceful disconnects will also be notified (sudden power offs, network disruptions, etc.).

Targets Topic (Vector Analytic ONLY)

The Vector4D device supports sending the co-ordinate data for each tracked target in real-time over MQTT. This allows the end-user to build rich applications beyond people counting with Vector 4D features such as multi-unit target tracking and staff identification included, perhaps overlaying the information over a real-world representation of the installed environment, for example.

Data Format

The target data is delivered on a per-frame basis, regardless of whether any targets are currently being tracked. Data is delivered from the device to the broker at 15 frames per second.

The target data is delivered as little-endian binary data with no packing. The first byte is the target data format byte. This byte will always be present. If packet type is >=1, the next 8 bytes are timestamp (type 0 contained no timestamp). This is the number of milliseconds that have elapsed since 1 Jan 1970 (Unix Epoch time).

The packet ends here if no targets are present for this frame. If targets are present, the data continues with 15 bytes per target, packed as follows:

Live Counts Topic

Similar to the Counts Topic but sent whenever there is a register change.

This is a retained topic on server.

An example is shown below:

{ 
"counts":
      [{
           "count":0,"id":0,"name":"Boardroom in"
      },{
           "count":0,"id":1,"name":"Boardroom out"
      },{
           "count":0,"id":2,"name":"Toilet in"
      },{
           "count":0,"id":3,"name":"Toilet out"
      },{
           "count":995,"id":4,"name":"KitchenDoorIn"
      },{
           "count":992,"id":5,"name":"KitchenDoorOut"
      },{
           "count":21000,"id":6,"name":"PIR"
      },{
           "count":1,"id":7,"name":"Occupancy"
      },{
           "count":674,"id":8,"name":"Occupancy Reset"
      },{
           "count":0,"id":9,"name":"Occupancy Wait"
      }], 
"index": 471, 
"time": "2020-12-17T11:19:46+0000" 
}

Device Info Topic

The Device Info Topic is sent on connection and when settings change.

This is a retained topic on the server. Example below:

{
      "deviceId":"D001",
      "deviceName":"CounterTest",
      "dhcpEnable":false,
      "ipV4Address":"192.168.1.120",
      "ipV6Address":"fe80::221:acff:fe04:125d",
      "macAddress":"00:21:AC:04:12:5D",
      "productId":"IRC6637CAW",
      "siteId":"S001",
      "siteName":"OriginOffice",
      "userString":"-" 
}

{"target":{"heightCM":0,"id":1841},"type":"TARGET_BIRTH"}

{"target":{"heightCM":164,"id":1841},"type":"TARGET_DEATH"}

{"name":"Line 2","target":{"heightCM":161,"id":1844},"type":"LINE_COUNT"}

{"name":"Line 2","target":{"heightCM":161,"id":1844},"type":"LINE_FWD_XING"}

{"name":"Line 1","target":{"heightCM":161,"id":1844},"type":"LINE_REV_XING"}

{"name":"Testing Zone","target":{"heightCM":0,"id":1841},"type":"POLYGON_BIRTH"}

{"name":"Testing Zone","target":{"heightCM":0,"id":1841},"type":"POLYGON_ENTER"}

{"name":"Testing Zone","target":{"heightCM":164,"id":1841},"type":"POLYGON_EXIT"}

{"name":"Testing Zone","target":{"heightCM":0,"id":1843},"type":"POLYGON_DEATH"}