Chiung-Yao FangHsiu-Lin HsuehSei-Wang Chen
National Taiwan Normal UniversityDepartment of Computer Science and Information Engineering
Dangerous Driving Event Analysis Systemby a Cascaded Fuzzy Reasoning Petri Net
Outline
IntroductionSystem flowchartCascaded fuzzy reasoning Petri netDangerous driving event analysis
systemExperimental resultsConclusions and future work
Introduction
Driver assistance systemPassive methodsActive methods
Active driver assistance systemDetection componentAnalysis component
Block Diagram of an Active DAS
Analysiscomponent
Detectioncomponent
Sensor 1
Sensor 2
Sensor n
Detection system 1
Detection system 2
Detection system n
Dangerous driving event analysis system
Warning output
…
…
Flowchart of the Analysis System
Start
Data acquisition
Driving event integration
Degree of danger computation
Degree of danger output
Behavior analysis of our vehicle
Interaction analysis between nearby vehicles
and our vehicle
CFRPN
Cascaded Fuzzy Reasoning Petri Net (CFRPN)
operation) production-(maxfunction inference :
vectorparameter :C
then ,1 If or.input vect :
output final theis then , If tor.output vec :
,C ,
stage,th in the FRPNth For the
f
XUjU
YMjY
UfY
ji
ji
ij
ij
i
ji
ji
ji
ji
ji
The Production Rules of FRPN
Rule 1:
where : confidence vector of rule associated with the only corresponding transition
Rule 2:
where : confidence vector
of the rule related to the
corresponding m transitions
)( jj CR
)()(...)()( 112211 mmmm PPPP
)( jj CR
)()(...)()( 112211 mmmm PPPP T
21 ],...,,[ mj cccC
][cC j
cmm },...,,min{ 211
},...,,max{ 22111 mmm ccc
)( 22 P
)( 11 mmP
)( 11 P
)( mmP
c
)( 11 P
)( 22 P
)( mmP
2c
mc
1c
)( 11 mmP
Fuzzy Reasoning Algorithm
over. is reasoning theotherwise,
3; Step return to ,1 then ,or If 4) Step
from Compute (3)
from Compute (2)
1 if ,1
1 if
Compute (1)
3) Step
.0Let 2) Step
. and , , , , :inputs initial FRPN Read 1) Step
11
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1
1
1
,
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, rpIxx
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Some Terminology
Lateral distanceForward distance
Our vehicle
Right-front
vehicle
Forward distance
Lateral distance
Using FRPNs for Reasoning
An example Get the membership
values of Lateral distance Position Speed
Input to the fuzzy reasoning Petri net Speed change reasoning Lane change reasoning Integration
Our vehicle
Preceding vehicle
Following vehicle
Left-rear
vehicle
Right vehicle
Left-front
vehicle
Right-front
vehicle
Left vehicle
Right-rear
vehicle
Membership Functions
Lateral distance
Position
Speed
Lateral distance (m)
Position (m)
Speed (km/hr)
Example of Lane Change Reasoning
Vo : our vehicle
Vlf : left-front vehicle
(1) : Vo moves without lane change.
(2) : Vo changes to the left lane.
(3) : Vo changes to the right lane.
(4) : Vlf moves without changing lane.
(5) : Vlf changes to the left lane.
(6) : Vlf changes to the right lane.
(7) : Vlf and Vo are moving in the same lane.
(8) : Vlf and Vo are moving in different lanes.
)( 11 p
)( 22 p)( 33 p
)( 44 p
)( 55 p)( 66 p
)( 77 p
)( 88 p
Example of Lane Change Reasoning
Two production rules:
: occurrence possibility that “Vlf and Vo are moving in the sa
me lane.”
: occurrence possibility that “Vlf and Vo are moving in differe
nt lanes.”
7
)())()(())()(( 7744226611 ppppp
)())()((
))()(())()(())()((
))()(())()(())()((
886633
553344336622
552255114411
ppp
pppppp
pppppp
8
Corresponding FRPN
: left-front vehicle and
our vehicle are moving in
the same lane
: left-front vehicle
and our vehicle are moving
in different lanes
)( 77 p
)( 88 p
Example of Speed Change Reasoning
Vo : our vehicle
Vlf : left-front vehicle
(1) : forward distance between Vlf and Vo is close
(2) : speed of Vo is slower than that of Vlf
(3) : speeds of Vlf and Vo are equal
(4) : speed of Vo is faster than that of Vlf
(5) : forward distance between Vlf and Vo increases
(6) : forward distance between Vlf and Vo remains the
same
(7) : forward distance between Vlf and Vo decreases
)'(' 77 p
)'(' 66 p
)'(' 55 p
)'(' 44 p
)'(' 33 p
)'(' 22 p
)'(' 11 p
Example of Speed Change Reasoning
Three production rules:
To decide the occurrence possibilities of the following driving ev
ents:
Forward distance between Vlf and Vo increases
Forward distance between Vlf and Vo decreases
Forward distance between Vlf and Vo remains unchanged
)'(')'(')'(' 552211 ppp
)'(')'(')'(' 663311 ppp
)'(')'(')'(' 774411 ppp
Corresponding FRPN
: forward distance between
Vlf and Vo increases
: forward distance between
Vlf and Vo remains the same
: forward distance between
Vlf and Vo decreases
)'(' 55 p
)'(' 66 p
)'(' 77 p
Integration
Integration rule:
: degree of danger of the interaction be
tween Vlf and Vo
)"("))'(')(())'(')((
))'(')(())'(')((
))'(')(())'(')((
77886688
55887777
66775577
ppppp
pppp
pppp
"
Freeway Driving Event SimulationObjective – provide experimental
data
Two major stages:Simulation of freeway environments Simulation of vehicle behaviors
Simulation of Freeway Environments
Given: Total length of the freeway Number of toll stations, tunnels, freeway entries
and exits
Produce: Total lengths of tunnels Locations of toll stations, tunnel entries and
exits, freeway entries and exits Locations of road signs
Simulation of Vehicle BehaviorsGiven :
Vehicle positions and moving directions (of our vehicle and nearby vehicles)
Produce : Vehicle speed Lateral distance Directional signal Braking signal
Our vehicle
Preceding vehicle
Following vehicle
Left-rear
vehicle
Right vehicle
Left-front
vehicle
Right-front
vehicle
Left vehicle
Right-rear
vehicle
Experimental Results
Conditions:Our vehicle moves without lane change.The left-front vehicle changes its lane to the
right.The speed of our vehicle is faster than that of
the left-front one.
Experimental Results
0.724
0.953
0.971
0.002
0.000
0.131
0.731
0.731
0.022
0.131
0.015
0.802
0.227
0.047
0.002
0.000
Left-front vehicle and our vehicle are moving in the same lane
Distance between left-front vehicle and our vehicle decreases
Our vehicle moves without changing lane
Our vehicle is faster than the left- front
one
Left-front vehicle
changes lane to the right
Dangerous
Degrees of Danger of Interactions Between Left-fr
ont Vehicle Vlf and Our Vehicle Vo
No. Speed of Vo– speed of Vlf (Km
/hr)
Forward distance between Vo and V
lf (meter)/(second)
Horizontal shift of Vo (meters)
Horizontal shift of Vlf (meters)
Degree of danger
1 -15 50/2.25 0 2 0.073
2 -15 50/2.25 -2 0 0.073
3 0 50/2.25 0 2 0.181
4 0 50/2.25 -2 0 0.181
5 15 50/2.25 -2 0 0.266
6 15 30/1.35 0 0 0.439
7 15 30/1.35 0 2 0.724
8 15 10/0.45 0 2 0.922
9 15 10/0.45 0 0 0.572
Degrees of Danger of Interactions Between Prece
ding Vehicle Va and Our Vehicle Vo No Speed of Vo–
speed of Va
(Km/hr)
Distance
between Vo and Va
(meter)/(second)
Horizontal
shift of Vo
(meters)
Horizontalshift of Va
(meters)
Degree ofdanger
1 -15 50/2.25 0 2 0.037
2 -15 50/2.25 -2 0 0.037
3 0 50/2.25 0 2 0.181
4 0 50/2.25 -2 0 0.181
5 15 50/2.25 -2 0 0.261
6 15 30/1.35 0 0 0.724
7 15 30/1.35 0 2 0.709
8 15 10/0.45 0 2 0.903
9 15 10/0.45 0 0 0.943
Conclusions and Future Work Dangerous driving event analysis system
Reasoning by a cascaded FRPN module Detection subsystem integration Warning drivers Future work: integrate into the driver assistance
system
Freeway driving event simulation system Provide experimental data Support other driver assistance subsystems Future work: include more road conditions