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SAE J2735-Draft-Rev29 [issued: 12-11-08]
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71 -
This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
</xs:sequence>
</xs:complexType>
In addition, this item may be used by data structures in other ITS standards.
Remarks: From the VII POC-A team.
6.40 Data Frame: DF_Snapshot
Use: A report on one or more status elements in the vehicle which may have changed along with a set of
position and heading elements representing the location of the report. Each report can contain status
information on a number of defined vehicle devices.
ASN.1 Representation:
Snapshot ::= SEQUENCE {
thePosition FullPositionVector,
-- data of the position and speed,
datSet SEQUENCE (SIZE(0..31)) OF VehicleStatus,
-- a seq of data frames
-- which encodes the data
... -- # LOCAL_CONTENT
}
XML Representation:
<xs:complexType name="Snapshot" >
<xs:sequence>
<xs:element name="thePosition" type="FullPositionVector" />
<!-- data of the position and speed, -->
<xs:element name="datSet" >
<xs:complexType>
<xs:sequence minOccurs="0" maxOccurs="31">
<xs:element name="datSet-item" type="VehicleStatus" />
<!-- a seq of data frames which encodes the data -->
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="localSnapshot" type="local:Snapshot" minOccurs="0"/>
</xs:sequence>
</xs:complexType>
Used By: This entry is used directly by one other data structure in this standard, a MSG called
MSG_ProbeVehicleData <ASN> <XML>. In addition, this item may be used by data structures in
other ITS standards.
6.41 Data Frame: DF_SnapshotTime
Use: To allow Network Users to change the snapshot collection policy based in elapsed time. Two times
and two speeds are included in the message T1, S1 and T2, S2 to be used by the OBE as follows:
If speed is
= S1 then time to next snapshot is T1
- default 20 mph (8.9 m/s) and 6 secs
If speed is
= S2 then time to next snapshot is T2
- default 60 mph (26.8 m/s) and 20 secs
If speed is > S1 and < S2 then time to snapshot is linearly interpolated between T1 and T2
If S1 is set to zero then the time to the next snapshot is always T1
ASN.1 Representation:
SnapshotTime ::= SEQUENCE {
t1 INTEGER(1..99),
-- m/sec - the instantaneous speed when the
-- calculation is performed
s1 INTEGER(0..50),
-- seconds
t2 INTEGER(1..99),