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Unit Description

  • Name: BACnet-Thing
  • Picture: BACnet-Thing.jpg
  • Logo:
  • Hardware: Off-the-shelf DXR2 BACnet controller, KNX room unit, lighting controller, blinds controller, I/O board
  • Software: BACnet firmware (DXR2) and ThingWeb-based BACnet IP to CoAP/HTTP gateway (Java)
  • WoT functions:
    • Role: Server only
    • Protocols: CoAP, HTTP, BACnet IP
    • Encodings: JSON, ASN.1
    • Discovery: Automatic TD Repo registration and keep-alives
    • Application logic: Exposing BACnet objects as (composed) Things
  • The BACnet-Thing provides Properties to read the room temperature, air quality, and occupancy. There are Properties to read/write the temperature setpoint, control the lights, a fan, and a valve. Actions are used to control the blinds and run a temperature control loop. Events allow to subscribe to value changes and alarms. The gateway based on ThingWeb is application-agnostic and can discover any BACnet object. A BACnet and a building automation ontology is used to convert the discovered objects to Thing Description. All BACnet operations are provided as WoT interactions using a BACnet protocol binding, which is also used internally to proxy from BACnet to CoAP and HTTP.