Skip to content

WZDx Specification v4.0
Compare
Choose a tag to compare
@j-d-b j-d-b released this 15 Dec 23:18
· 30 commits to main since this release
v4.0
7df0a7e
This commit was created on GitHub.com and signed with GitHub’s verified signature. The key has expired.
GPG key ID: 4AEE18F83AFDEB23
Expired
Learn about vigilant mode.

WZDx version 4.0 implements clean up and small additions in functionality to the WZDx feed and adds definitions for two new feeds, the SwzDeviceFeed and RoadRestrictionFeed. Until version 4.0, the WZDx specification defined only one feed, the WZDxFeed.

Features

  • Add the following values to the VehicleImpact enumerated type:
    • some-lanes-closed-merge-left
    • some-lanes-closed-merge-right
    • all-lanes-open-shift-left
    • all-lanes-open-shift-right
    • some-lanes-closed-split
    • flagging
    • temporary-traffic-signal
  • Allow restrictions with a value and unit to be provided at the road event level; specifically:
    • Rename the LaneRestrictionUnit enumerated type to UnitOfMeasurement.
    • Rename the RoadRestriction enumerated type to RestrictionType.
    • Rename the LaneRestriction object to Restriction and remove the lane_restriction_ prefix from its properties.
    • Rename the Restriction object units property to unit.
  • Add values parking and median to the LaneType enumerated type.
  • Define a new data feed, the RoadRestrictionFeed and RestrictionRoadEvent to enable providing a feed of restrictions on roadways, such as bridge clearances.
  • Define a new data feed, the SwzDeviceFeed, to enable equipment vendors and manufacturers to provide high-level information about deployed field devices in work zones. A SwzDeviceFeed contains a new feature type, the FieldDeviceFeature, which contains information about a specific type of field device. The following field devices are defined in WZDx v4.0:
    • ArrowBoard: An electronic, connected arrow board which can display an arrow pattern to direct traffic.
    • Camera: A camera device deployed in the field, capable of capturing still images.
    • DynamicMessageSign: An electronic traffic sign deployed on the roadway, used to provide information to travelers.
    • FlashingBeacon: A flashing beacon light of any form (e.g. trailer-mounted, vehicle), used to indicate something or capture driver attention.
    • HybridSign: A hybrid sign that contains static text (e.g. on an aluminum sign) along with a single electronic message display, used to provide information to travelers.
    • LocationMarker: Describes any GPS-enabled ITS device that is placed at a point on a roadway to dynamically know the location of something (often the beginning or end of a work zone).
    • TrafficSensor: A traffic sensor deployed on a roadway which captures traffic metrics (e.g. speed, volume, occupancy) over a collection interval.
  • Rename the workers_present property on the WorkZoneRoadEvent object to worker_presence; change the type from "boolean" to a new WorkerPresence object which enables providing more nuanced information about worker presence in work zones.

Refactoring

  • Separate the v3.1 RoadEvent object into RoadEventCoreDetails (details that are shared by all specific types of road events) and specific types of road events (WorkZoneRoadEvent, DetourRoadEvent, and RestrictionRoadEvent) which each contain the RoadEventCoreDetails via a core_details property; update the RoadEventFeature properties property to be one of the specific road events types.
  • Move the location_method property from the FeedDataSource object to the WorkZoneRoadEvent object.
  • Change the reduced_speed_limit property on the WorkZoneRoadEvent to reduced_speed_limit_kph; change its type from "integer" to "number" and clarify that the value should be in kilometers per hour.
  • Deprecate the lane_number property on the Lane object.
  • Deprecate the lrs_type and lrs_url properties on the FeedDataSource object.
  • Remove the deprecated value alternating-one-way from the LaneStatus enumerated type.
  • Remove the following deprecated properties from the road event (RoadEvent in previous versions; WorkZoneRoadEvent and RoadEventCoreDetails in 4.0):
    • road_event_id
    • road_number
    • road_name
    • total_num_lanes
  • Remove the following deprecated values from the LaneType enumerated type:
    • left-lane
    • right-lane
    • middle-lane
    • center-lane
    • right-shoulder
    • left-shoulder
    • right-second-exit-ramp
    • left-second-exit-ramp
    • right-entrance-exit-ramp
    • left-entrance-exit-ramp
    • hov-lane
    • alternating-flow-lane
    • reversible-lane
    • right-entrance-lane
    • left-entrance-lane
    • left-entrance-ramp
    • right-merging-lane
    • left-merging-lane
    • right-second-entrance-ramp
    • left-second-entrance-ramp
  • Require the road_names property on the RoadEventCoreDetails.
  • Require the id property on the RoadEventFeature.
  • Refine the LaneType enumerated type; specifically:
    • Rename lane to general.
    • Remove right-turning-lane and left-turning-lane.
    • Remove right-exit-lane and left-exit-lane.
    • Add exit-lane.
    • Remove right-exit-ramp and left-exit-ramp.
    • Add exit-ramp.
    • Remove right-entrance-ramp and left-exit-ramp.
    • Add entrance-ramp.
    • Add entrance-lane.
  • Deprecate the location_verify_method property on the FeedDataSource.
  • Update the SpatialVerification enumerated type value descriptions to clarify that verified work zone locations should use a GPS enabled device.
Assets 2