lecture slides (driver assistance and vehicle control)

Driver Assistance and

Vehicle Control

TNK052 Intelligent TransportationSystems

Andreas Tapani

2

Driver Assistance today and

in the 1930’s

The driver had to do everything!

ABS, ESP, automatic transmission,

rain sensors, panic brake assistant, …

The driver indicates direction and speed,

the car takes care of the rest!

3

The road safety development in Sweden

Source:

SCB

Fatalities per 100 000 cars

4

Driver error

86%

Technical failure

3%

Unknown

11%

Single vehicle

21%

Turning/crossing

30%

Vehicle-

pedestrian

18%

Rear-end

13%H

ead-on

10%

Other

8%

Accident statistics

�~1.2 million people killed in road traffic accidents each year

�~40 000 in the EU

�~450 in Sweden

�Nearly all accidents are

due to human error!

5

Road safety improvement strategies

�Passive counterm

easures:

Reduce consequences of

errors/accidents

�Active counterm

easures:

Reduce the number of

driver errors

6

In-vehicle ITS or “Advanced

Driver Assistance Systems”

(ADAS)

7

Estimations of the accident reduction potential

of ITS related to vehicle safety

�80 %

reduction in total accidents (Japan)

�ISA: 25-30 %

reduction (Netherlands)

�ACC: 60 %

reduction in rear-end accidents (Netherlands)

How are this type of estimations done?

8

Other potential effects on the traffic system

�Increased capacity

�Reduced travel times

�Reduced environmental impact

9

Examples of available

ITS in series-produced

passenger cars

10

Driver monitoring

�A simple form

: passengerdetectionfor seatbelts

�Detectingdriver impairmentor distraction

�Camera technology

�(Biosignalmeasurements)

11

Night vision

�To allowdriversto gaintime to assessthe situation and choose

and appropriateresponse

�Near or Far InfraRed(NIR or FIR) technology

12

Workloadmanagement

�Filteringand prioritizingthe inform

ation presentedto the driver

�Estimationof the driver workloadusingvehiclesensors

(speed brakeforce, windshieldwiperuse)

�Whenchallengingsituations are detected�

Postponeor

cancelnon-urgentwarningsor mobile phonecalls.

13

Brakeforcedisplay

�Display brakeforce

throughthe brakelights

14

Adaptive headlights

�Headlightsthat followthe road curvature

�Switchbetweenhigh and lowbeam

�Corneringheadlights

�Safetyeffects? (Improvedsight�

Higherspeeds �

reducedsafety?)

15

Lane departure

warning

�Recognize lanes and detect an

imminent lane departure

�Cameras

�Lane markings are required

�Lane keeping assistant:

�Provide appropriate steering

input

�Responsibility and legislation

issues

16

Adaptive Cruise Control (ACC)

�Mantainspeed and distance

to the vehicleinfront

�Engine decelerationor

Activedecelerationwith

limitedbrakeforce

�Earlysystems: lim

itedspeed

range

New systems: Full speed

rangeincludingstop and go

�Ongoingdevelopment:

Linkagebetweenthe ACC

and navigation

17

Electronic stabilitycontrol

�Brakingof individualwheels

(suspension and traction

control)

�One of the mostsafety-

enhancingsystems on the

market

�Sensors: Steeringwheel

angle, gyro, yawratelateral

and longitudinal accelation

�(Countersteeringassistance)

�Roll stabilitycontrol

�Takeinto

accountthe load

distribution

18

Blind spotdetectionsystems

�Detectingobjectsin the ”blind spot”sideand back

�Cameras or radar

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Pre-collision, collisionavoidanceand

obstacledetectionsystems

�Avoidcrashesand reducethe severityof imminentcrashes

�Lowervehiclespeed

�Driver warningand brakesupport

20

Emergencysteeringand breakingassist

�Optimizingthe vehicledecelerationor steeingin emergency

situations

�Maxmizingpressure

in the brakecircuits

�Reducesteeringgearratio

�Shortenstoppingdistance

�More

directsteering

�Autonomousbrakingsystems are alsoavailable

�a potential to avoidaccidents

21

Passengerinjurymitigationand

post-crashsystems

�Activewhiplashinjuryreduction

�Monitor the rear of the carusingradar

�Repositionheadrest before

a rear-end

crash

�Advancedairbags

�Adaptthe deploymentpower according

to �Collisionseverity

�Massof the driver

�Partialwindowopening, doorunlocking

and engineand fuelcutoff

�Automaticemergencycall–notifythe

rescueservice automatically

22

Co-operative systems

Vehicle-to-vehicle and

vehicle-to-infrastructure communication

23

Driver assistance systems technology

Source: PREVENT IP

24

ADAS control loop

Surveillance of

the vehicle

environment

Traffic situation

interpretation

Activate intervention system

Prediction of

future situation

Critical?No

Yes

25

System classification

Comfort

Safety

Inform

ativ

eLow

response

High

response

Response

time

>

Driver

reaction

time

Response

time

<

Driver

reaction

time

Intervention

Guidance

Navigation

ABS

ESP

CA

LDW

ACC

PA NAVIGATION

VISION ENH.

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Driver assistance systems and accident phases

Rescue

Occupant protection

Collision mitigation

Collision avoidance

Norm

al driving

Emergency

systems

Passive safety systems

High response systems

Inform

ation/

low response

Post Crash

Crash

Pre-crash

Intervention

Driving

Critical

situation

Point of no

return

End of

crash

Crash

27

28

In-vehicle ITS

road map

29

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PassengercarITS -focusareas in the

developmentprocess

31

Issues in the development process

�Technological requirement

�Driver acceptance and behaviouralresponse

�Driver, car manufacturer and system developer liability

32

Technological requirements

�Specifications

�Reliability

�Cost

…

33

Driver acceptance and behaviouralresponse

�Do drivers want the system?

�Will the driver use the system as intended?

�Behaviouraladaptation

�Is driver attention diverted from traffic due to the system?

34

Liability issues

�Who is responsible for an accident?

�Inform

ation systems

�Overridableintervention systems

�Non-overridableintervention systems

35

Evaluationof the effectsof in-vehicleITS

36

Methods for testing the impact of in-vehicle ITS

�Driving simulator studies

�Field trials

�Traffic modelling

�Economic analysis

37

What have we talked about today?

�Changes in the nature of driving

�Accident statistics

�An overview of in-vehicle ITS

�A peek to the future

�Issues that needs to be considered in the system

development process