session 21 andreas tapani

Trafiksimulering för utvärdering av fordonsbaserade ITS-tillämpningarAndreas Tapani

Förarstöd och andra ITS

Vilka blir effekterna?

Trafiksimulering ger svar!

Trafiksimulering för utvärdering av fordonsbaserade ITS

Traditionell trafiksimulering. Studier av framkomlighet vid olika:

Trafikstyning Vägutformning (nät, enskilda länkar/korsningar)

Trafiksimulering för utvärdering av fordonsbaserade ITS: ITS funktionalitet Skillnader i förar/fordonsbeteende Ytterligare tillämpningsområden (säkerhet, miljö)

Trafiksimulering för utvärdering av fordonsbaserade ITS

Trafiksimulering för utvärdering av fordonsbaserade ITS

Trafiksimulering av fordonsbaserade ITS:

Mera detaljerade och flexibla förar/fordonsmodeller!?

Analysis of rumble strips and driver fatigue

Infrastructure-based milled rumble strips

Vehicle-based ”virtual” rumble strips

Sleep deprived drivers accepted 4 % shorter distances to the closest oncoming

Average reaction time:Alert drivers 1.47 sSleep deprived drivers 1.63 s

Individual driver behaviour

Observations from a driving simulator study:

Alert and sleep deprived driving

Driving speed in free driving conditions Car-following reaction times Distance to oncoming vehicles at the

start of overtaking

Modelling rumble strips and driver fatigue

Rumble strips on two-lane highways: The simulation model must allow modelling of two-lane

highways The RuTSim model

Modelling of rumble strips and driver fatigue in RuTSim by modification of:

Desired speeds Reaction times Overtaking probabilities

Performance indicators

Average journey speed

Time-to-collision based safety indicators(with respect to oncoming vehicles during overtaking situations)

TTC

t

+ = TETi

TITi

TTC*

RuTSim simulations

Driver behaviour data and road alignment from the driving simulator study

Simulations of traffic with No rumble strip Milled Rumble strip In-vehicle rumble strip Varying percentages of sleep deprived drivers

0 5 10 2590

91

92

93

94

95(a) No rumble strip

Alert

Sleep deprived

0 5 10 2590

91

92

93

94

95(b) Milled rumble strip

Ave

rage

jour

ney

spee

d [k

m/h

]

0 5 10 2590

91

92

93

94

95(c) In-vehicle virtual rumble strip

Percentage of sleep deprived drivers [%]

0 5 10 253

3.5

4

4.5

5(a) No rumble strip

Alert

Sleep deprived

0 5 10 253

3.5

4

4.5

5(b) Milled rumble strip

Ave

rage

TET

[s]

0 5 10 253

3.5

4

4.5

5(c) In-vehicle virtual rumble strip

Percentage of sleep deprived drivers [%]

0 5 10 25

6

7

8

(a) No rumble strip

Alert

Sleep deprived

0 5 10 25

6

7

8

(b) Milled rumble strip

Ave

rage

TIT

[s2 ]

0 5 10 25

6

7

8

(c) In-vehicle virtual rumble strip

Percentage of sleep deprived drivers [%]

Results

050

100150200250300350400450500550600650700750

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

t [s]

x [m

]

overtaker

preceding

opposing

opposing

Effekter av en ”omkörningsassistent”

Overtaking Assistant on the N305

Almere - Zeewolde, 15 km long, 8 m wide

1. Current situation2. Overtaking Assistant threshold3. Overtaking Assistant penetration level

The Overtaking Assistant in RuTSim: Changed driver willingness to overtake Calculate time to oncoming vehicle, commence overtaking if

longer than the assistant threshold

510 25 50 1005

10

15

20

25

30

35

40

Assistant penetration level [%]

OF

[#

/ (km

h

1000

veh

]

A-Z

510 25 50 1005

10

15

20

25

30

35

40

Assistant penetration level [%]

Z-A

Assisted

Non-assisted

8 9.5 11 12.5 14

10

20

30

40

A-Z

Assistant threshold [s]

OF

[#

/ (km

h

1000

veh

]

8 9.5 11 12.5 140

10

20

30

40

Assistant threshold [s]

Z-A

Assisted

Non-assisted

Resultat (exempel)

Simulering av trafik i olika regioner

Skillnader mellan geografiska (kulturella) områden Olika regler Olika beteende

Risk för ogiltiga modellantaganden

Vehicle Trajectory Impacts of Adaptive Cruise Control

Adaptive Cruise Control (ACC): fixed speed cruise control extended with a distance controller

ACC is primarily marketed as a system for increased driver comfort

ACC has a potential to influence:● Capacity?● Safety?● Traffic’s environmental impact?

Studies of ACC

Driver behaviour in ACC-equipped vehicles

● Reduced attention

● Over-reliance on the system

● Changes in speeds and desired following distances

Effects of ACC on the traffic system

● Traffic simulation based analyses Capacity and speeds

This study

Impacts of ACC on vehicle acceleration and deceleration rates Simulation of mixed traffic including

ACC-equipped and standard vehicles Consequences of observed driver behavioural changes

Car-following modelling of ACC-equipped and standard vehicles:

ACC-vehicles: (IDM, Treiber et al. 2000)

Standard vehicles: (HDM, Treiber et al. 2006)

• IDM + human reaction delays, anticipation and perception errors

• Full speed range ACC – system limitations and driver acceptance is not considered

An indicator of vehicle trajectory smoothness

Acceleration noise (ACN)

ACN for ACC-equipped and standard vehicles

Equal desired following distancesand speeds for ACC-equipped and standard vehicles

Sammanfattning

● Trafiksimulering ger möjlighet att analysera trafiksystemeffekter av förarstöd och andra ITS

● ITS-tillämpningens funktionalitet och inverkan på förarbeteendet påverkar simuleringsresultaten

● Fortsatt forskning Förarbeteende och trafiksimulering Sambandet mellan simuleringsbaserade indikatorer och

effekter i verklig trafik “Co-operative systems”