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TrafficXRoads: Guide
We publish the data using data sinks or widgets that are available in other parts of the
Programming elements
panel. We use the widgets when we want to see the data on the
dashboard or if we want to use them in expressions for controlling relays or an SDLC
interface.
We
use
the
UDP/REST
sinks when the FLOW device is connected to a device that can uses data communication.
For traffic control in almost all cases the UDP sinks are used. REST sinks are used for
communication with smart city and data platforms.
Detection outputs – communication with traffic controller
The individual detected traffic events can be sent into the traffic controller via different
type of interfaces – both data interfaces and physical interfaces (such as relay interface).
The TrafficXRoads unit support multiple data interfaces including REST API, WEBHOOKs
and UDP. For the data communication between the unit and the controller to work, the
controller needs to support the specific data communication interface. Next we will cover
interface that are used in traffic most widely – UPD and SDLC as well as the physical relay
interface. For all of these interfaces we will continue with our model example from the
previous chapter and do so by creating “basic object presence detectors”.
The data interfaces can be only used for controllers that have
implemented the specific interface. Whether or not the data interface is
supported should be verified with the traffic controller manufacturer.
Alternatively you can contact us at
The FLOW data interfaces are documented here:
. If you are a traffic controller
manufacturer or an integrator and you would like to integrate a some of
the data interfaces, don’t hesitate to get in touch at
We will gladly help you with the integration.
UDP data interface
The UDP data interface works based on the subscribe model, where the traffic controller
connects to the FLOW device as a client. Once the UDP sink is subscribed the controller
will start receiving data from all the defined UDP sinks and analytics.
FLOW supports two types of UDP sinks - ZONE sink and a CATEGORY COUNT sink. ZONE
sink sends data about object presence (a list of object IDs) that are on the output of the
specific operator. The data are always sent on a subscribe or when the value changes on
a specific sink. Data from the CATEGORY COUNT sink are sent only when the controller
requests this data.
