Download Blink behaviour based drowsiness detection

Table of contents
1
Introduction ..................................................................................................................1
1.1
Background.............................................................................................................1
1.2
Problem definition...................................................................................................1
1.3
Outline of the thesis ................................................................................................1
2
Drowsiness and driving ................................................................................................3
2.1
Accidents caused by drowsy drivers ........................................................................3
2.2
Methods used for drowsiness detection ...................................................................3
2.2.1
Physiological measures....................................................................................3
2.2.2
Driving performance measures ........................................................................4
2.2.3
Self-report .......................................................................................................4
2.2.4
Expert ratings ..................................................................................................5
3
Electrooculogram (EOG)..............................................................................................7
3.1
Origin of the EOG signal.........................................................................................7
3.2
Measurement of EOG..............................................................................................7
3.3
Blink detection........................................................................................................8
4
Electroencephalogram (EEG) ....................................................................................11
4.1
Origin of the EEG signal .......................................................................................11
4.2
Classification of EEG............................................................................................11
4.3
Measurement of EEG............................................................................................12
4.4
EEG measurement problems .................................................................................13
5
Changes in EOG and EEG during drowsiness ..........................................................15
5.1
EOG as an indicator of drowsiness ........................................................................15
5.1.1
PERCLOS .....................................................................................................16
5.2
EEG as an indicator of drowsiness ........................................................................16
5.3
Objective Sleepiness Scoring (OSS)......................................................................17
6
Drowsiness stages based on blink behaviour .............................................................19
6.1
Model for drowsiness stages..................................................................................19
6.2
Drowsiness detection program ..............................................................................20
7
Background Summary................................................................................................23
8
Material.......................................................................................................................25
8.1
Drowsiness program..............................................................................................25
8.2
Collection of data..................................................................................................26
9
Method and procedure ...............................................................................................29
9.1
Method .................................................................................................................29
9.1.1
Common concepts .........................................................................................29
9.1.2
Hypothesis ....................................................................................................30
9.1.3
Data processing and blink detection...............................................................30
9.1.4
Modifications of the program ........................................................................31
9.2
Procedure..............................................................................................................31
10
Results from development of method.....................................................................35
10.1 Blink detection......................................................................................................35
10.1.1 Errors found in program ................................................................................35
10.1.2 Modification of the blink detection program..................................................35
10.2 Blink frequency replaced by blink intervals...........................................................36
10.3 Linear model for boundaries..................................................................................36
10.4 Drowsiness program with KSS as reference ..........................................................38
10.4.1 Choice of linearity constants and boundaries .................................................38