Forum on Advanced Vehicle Safety Technology

Jan. 25 & 26, 2007

Human Factor Issues of Driving Assistance Systems

David BenedictGeneral Manager

Vehicle Performance & DevelopmentToyota Technical Center, U.S.A

Human Factor Issues of Driving Human Factor Issues of Driving Assistance SystemAssistance System

• Background• Assessment of Pre-Collision Driver Factors• Current Pre-collision System Capabilities• Development of a Driver Monitor System• Development Challenges• Future Research Needs

0020XX20XX

Nu

mbe

r of

cas

ual

ties

Nu

mbe

r of

cas

ual

ties

Zero-fatalities

Zero-fatalities

VehicleVehicle

Trafficenvironment

Trafficenvironment

BackgroundBackground

PeoplePeople

Fata

litie

s

Years

Seatbelt

AirbagMultiple airbags

Potential Fatality Reduction by Safety DevicesPotential Fatality Reduction by Safety Devices

Active Safety has a significant potential to reduce fatalities

Fata

litie

s

Passive Passive SafetySafety

Active Active SafetySafety

Driver visibility assistanceDriver visibility assistance--Blind corner monitorBlind corner monitor

--Adaptive Front light systemAdaptive Front light system

Driver assistanceDriver assistance--Lane departure warningLane departure warning--Lane Keeping assistLane Keeping assist

Advancement of Active Safety SystemsAdvancement of Active Safety Systems

2000

Safe drivingSafe driving

Accident Accident avoidanceavoidance

Accidentoccurs

Crash Crash predictionprediction --ABSABS

--TRCTRC--Brake assistBrake assist

--VSCVSC

Integrated controlIntegrated control

--VDVDＩＩMM

--NavigationNavigation--coordinated shift coordinated shift controlcontrol

AutonomousAutonomoussafety supportsafety support--Forward collisionForward collision

avoidance assistavoidance assistsystemsystem

Improvement of passive safetyImprovement of passive safetyby prognosticationby prognostication--PrePre--collision safety systemcollision safety system

Active safety

Dynamic Limit controlDynamic Limit control

ONOFF

Lane keeping assist

Pre-collisionsafety

Forward vehicle

Forward collision avoidance assist system

Obstacles

V V ––V & V & V V –– I Coop.I Coop.

SafetySafety

VSC & VDIM

VSC

VDIM

ITARDA Japan 2001

Total fatal/serious injury accidents (61,531 cases)Insufficient attentionto the road ahead

28%

71%Inadequate safety precautions

43%

Mis-judgement20%

Mis-operation 9%

(Frontal crash ；1,031 vehicles)No operation

39% Braking44%

Steering6%

Braking + Steering11%

Accident Cause Analysis in JapanAccident Cause Analysis in Japan

Relevant U.S Accident DataRelevant U.S Accident Data

No Avoidance

47%Braking47%

Braking & Strg6%

Perceptual Errors

17%Decision

Errors11%

Vehicle Speed

21%

Alcohol Impairment

20%

Driver Inattention

24%

Incapac.7%

“Relative Frequency of Unsafe Driving Acts…”Veridian/ NHTSA

n= 732 (NASS)

“100 Car Study”VTTI/ NHTSA

n= 15

HMI Principle of PreHMI Principle of Pre--Collision SafetyCollision Safety

1. The warning system should only be activated when a collision is imminent.

2. Warnings should be provided at the appropriate time so that the driver can perform an evasive maneuver

Pre-collision Brake Assist

Pre-collision Seat Belts

Suspension ControlThe pre-collision sensor detects forward obstacles and determines in advance whether a crash is imminent.

Pre-collision Sensor

Pre-Collision System – Reducing collision damage

•Near Infrared Camera

•Near Infrared LED

•Image Processor

Driver face direction sensor

Time to collision

Collision▼

01234

FrontNon-Front

Advance warning

Monitoring the driver

Warning Timing of Advanced PCS

0

10

20

30

-80 -60 -40 -20 0 20 40 60 80Ho rizontal Ang le (deg)

0

10

20

30

-80 -60 -40 -20 0 20 40 60 80Horizontal Angle (deg)

Freq

uenc

y (%

) Outside Rear View(P assenger's Side)

Inside Rear ViewOutside Rear View (Driver's Side)

0

10

20

30

-80 -60 -40 -20 0 20 40 60 80Horizontal Angle (deg)

Freq

uenc

y (%

)

In-VehicleDisplay

Side View(Passenger's Side)

Side View(Driver's Side)

Non-front status

Front status

Example of Human Factor Research

Some Challenges of Developing a Driver Face Monitor

• Robust driving scenarios• Differentiation of mirror checks and

secondary task or outside glances.• Repeatable, accurate visual images

– Facial differences– Varying lighting conditions– Corrective or sunglasses

Future HMI Research Needs Related to AVST

• Improved human models to more accurately define driver mental/physical condition (inattention, drowsiness, drunk,)

• Data regarding human behavior & information needs with cooperative safety systems (V-V, V-I, etc.)

• Pre-collision driver behavior data and interaction with AVST

• Recommendations for optimal stimulus for restoration of drivers’ attention ( voice, vibration, smell, etc).

• Enhanced & accessible research databases

END