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SAE J2735-Draft-Rev26 [issued: 09-18-08]
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77 -
This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
thePosition FullPositionVector, -- data of the position and speed,
cntVSDTs INTEGER (0..31), -- a count of how many vehicle
-- status device type entires
-- will follow, 1 byte
deviceData SEQUENCE (SIZE(0..31)) OF
SnapshotItem, -- a seq of name-value pairs
-- which me may encode in the
-- style as other msgs, need to see
... -- # LOCAL_CONTENT
} -- Est size 2 bytes per payload item plus 10 for next position
XML Representation:
<xs:complexType name="Snapshot" >
<xs:annotation>
<xs:documentation>
Est size 2 bytes per payload item plus 10 for next position
</xs:documentation>
</xs:annotation>
<xs:sequence>
<xs:element name="thePosition" type="FullPositionVector" />
<!-- data of the position and speed, -->
<xs:element name="cntVSDTs" >
<xs:simpleType>
<xs:restriction base="xs:unsignedByte">
<xs:maxInclusive value="31"/>
</xs:restriction>
</xs:simpleType>
</xs:element>
<!-- a count of how many vehicle
status device type entires
will follow, 1 byte -->
<xs:element name="deviceData" >
<xs:complexType>
<xs:sequence minOccurs="0" maxOccurs="31">
<xs:element name="deviceData-item" type="SnapshotItem" />
<!-- a seq of name-value pairs which me may encode in the style as
other msgs, need to see -->
</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.
6.44 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 nex
t 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),
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