V* - Headers Describing Observation Records


Observation Record Fields

Indicates the fields recorded in each observation (vehicle) record

VV vfield1[,vfield2...]
vfield(x) [REQUIRED]

This parameter may be repeated

A Value for this parameter must be one of the following:
Value Units Meaning More Information
vehicleid Vehicle ID 64-bit (signed) integer value representing a sequence number
speed FU speed Observed speed Negative values means reverse direction.
naxles Number of axles
wbase FU length Wheelbase Distance between the first and last axle of a vehicle
length FU length Length Length of the observation
overhang FU length Overhang Length of the portion overhanging the back axle
delay seconds Delay Duration of time a vehicle was delayed or parked
chassisheight FU length Chassis height Height of a vehicle chassis above the surface
chassiscode Chassis code A vehicle chassis code can be any Long integer value
width FU length Width Width of the observation
height FU length Height Height of the observation. This is how tall the object is, not its height above sea level.
mass FU mass Mass Mass of the observation
masstare FU mass Tare Mass Tare mass of a vehicle. This can also be called the 'curb weight' or 'unladen weight'.
masslegal FU mass Legal Mass Legal mass of the vehicle
color 6-digit RGB Color The measured vehicle color. Eg FF0000 is 'red'
center FU length Distance from center Distance from the center of the lane
tsig Traffic Signal State of the traffic signal controlling the vehicle
vclass Type Class (primary) An observed type classification which may be defined in the 'TC' header field
vclass1 Type Class (alternate 1) An alternate (1) type classification
vclass2 Type Class (alternate 2) An alternate (2) type classification
vclassl Length Class A length classification. This property is derived by comparing against a length-based classification system which may be defined in the 'TL' header field
qc Quality Rating A numeric value assigned by the sensing equipment. This can explain how a vehicle was resolved (or 'coerced'), or whether the vehicle missed a sensor
tempair Degrees centigrade Air temperature
age Years Age Age of the observation: this may be a vehicle, its driver or a pedestrian
idtag ID Tag Identity tag of the observation such as its registration number
mac MAC Address MAC address of the observation. Default format is an unsigned Long value, not 6 hex values. See 'FU' header for details on how to change this format.
rssi Received Signal Strength Indicator (Since 1.261) Used for wireless or bluetooth devices. A value of 0 typically means full strength while a large negative value indicates low strength.
bttype Bluetooth Type (Since 1.261) Type of bluetooth device signal
  • 0 - Standard (V2 Bluetooth)
  • 1 - Low Energy Public (V4 Bluetooth)
  • 2 - Low Energy Random (V4 Bluetooth)
bayid Parking bay Identifier of a parking bay or berth
lat Degrees (-90 to 90) Latitude Latitude of the observation
lng Degrees (-180 to 180) Longitude Longitude of the observation
img Base 64 Image Image of the observation
imgfile URL Image File Reference to an image file of the observation


VV speed,vclass,wbase,naxles
Record speed, vehicle classification, wheelbase and number of axles.

Observation sub-component record fields

These fields describe subcomponents of an observation. For a vehicle record, these are axles.

VA axle_field1[,axle_field2...]
axle_field(x) [REQUIRED]

This parameter may be repeated

A Value for this parameter must be one of the following:
Value Units Meaning More Information
aspace FU length Axle spacing Spacing between the current axle and a leading axle. The first axle spacing is always zero.
amass FU mass Axle weight Weight on one axle
alrb From 0 to 100 Axle left/right balance How weight is distributed between the two sides of the axle. 0 means all weight is on the left side. 100 means all weight is on the right side. 50 means evenly distributed


VA aspace
Record inter-axle spacings