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SAE J2735-Draft-Rev28 [issued: 11-10-08]
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258 -
This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
In all seven of the following application scenarios, a working GPS unit
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and a connection to the vehicle
data bus, in addition to a DSRC radio unit, are necessary to send out the correct information to, and receive
the necessary information from, other vehicles.
Annex C-1 Intersection Collision Warning[RS7]
Application Description
This application warns drivers when a side-impact or straight crossing path collision at an intersection is
probable. DSRC communications can be used to allow a vehicle approaching an intersection to detect all
nearby vehicles, their position, velocity, acceleration, and turning status. The in-vehicle unit analyzes these
parameters for the other vehicles as contained in their MSG_BasicSafetyMessageFrame, Part I and
MSG_BasicSafetyMessageFrame, Part II messages and projects expected future vectors for these vehicles.
If this analysis determines that a collision is likely, an appropriate warning is issued to the driver.
Flow of Events
Flow of events
1.
Vehicle “A” sends MSG_BasicSafetyMessageFrame,
2.
Vehicle “B” receives message
3.
Vehicle “B” process the message from Vehicle A and determines that Vehicle A’s message
is relevant (crossing road segment via map and/or heading)
4.
Vehicle “B” alerts its driver to a straight crossing path hazard.
Hardware Devices:
DSRC radio
Positional and vehicle sensors
Human-Machine Interface
Occupant
Vehicle
System
Driver
Passenger
Service
Provider
Road
Department
Actors: (What entities play an
active role in use)
X
X
Support information:
CAMP-VSC Task 3 Report, 2003
Concept of Operations
For this application, it is assumed that all identified subject vehicles would be equipped with DSRC units. It
is also assumed that messages from each vehicle would be sent to conflicting vehicles on other intersection
legs, necessitating clear line of sight or relaying techniques.
Upon receipt of each broadcast of MSG_BasicSafetyMessageFrame, Part I message, the recipient needs to
implement an algorithm to determine if a crossing path conflict is present. Once a conflict is determined
the vehicle could use appropriate human machine interface (HMI) techniques aboard the vehicle to issue a
warning to the driver.
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Which is presumed to be able to provide position, velocity, and current time values for the vehicle.