tom

0

CVEN 4405 Human Factors in Civil and Transport Engineering

Term 3 2020 Week 1 - Lectures 1a and 1b

PRESS RECORD BUTTON

+

SHARE SCREEN

+

PRESS AUDIO BUTTON

1

Lecture Recordings

PLEASE NOTE.

All lectures today are being recorded.

Participation in this meeting indicates your consent to be included in the meeting recording.

2

Welcome to CVEN 4405 Human Factors in Civil and Transport

Engineering

CVEN4405: Human Factors in Civil and Transport Engineering

Introduction to the Course: Definition, History and Scope of

Human Factors

Week 1, Lecture 1a

4

Course Coordinator and Lecturer

Prof. Michael Regan, PhD Professor of Human Factors

Research Centre for Integrated Transport Innovation (rCITI) School of Civil and Environmental Engineering

UNSW Sydney

E: [email protected] Staff Webpage

5

The CVEN 4405 Teaching Team

Coordinator and Lecturer Prof. Michael Regan Professor of Human Factors Research Centre for Integrated Transport, UNSW Sydney E: [email protected]

Teaching Fellow Dr Prasannah Prabhakharan Research Fellow Research Centre for Integrated Transport, UNSW Sydney E: [email protected]

Demonstrator Mitch Cunningham E:[email protected]. au

6

Lecture 1a - Overview

• Housekeeping

• Your coordinator - me

• Course details

• Human factors – definition

• Human Factors - benefits

• Human Factors – short history

• Human Factors – scope

• Questions?

• Readings

Housekeeping

8

MS Teams, Moodle & Zoom

There will be three online platforms that we will be using throughout this course:

• Microsoft Teams – for Lectures

• Moodle – for course Information & material, announcements, resources etc

• Zoom – for Tutorials

9

Microsoft Teams

Most of you will be familiar with the Microsoft Teams platform. But, just in case…

Icon Meaning

Video on/off

Microphone on/off

‘Chat’ box (under Show Conversation)

Raise hand

10

E-Housekeeping – Microsoft Teams

To ask question, write your question in the ‘chat’ box • Mention the slide number in your question • I’ll l aim to address the questions either:

– during the lecture, if time – after the lecture

During the lectures I’ll ask some discussion questions. • To respond, raise you hand - • I’ll select someone with their hand raised • If I select you, please turn your microphone on and speak.

11

E-Housekeeping – Lectures

• Use the same MS Teams link for all three Wednesday lectures

• Lectures WILL be recorded: • Lectures 1a and 1b (11-00am – 1-00pm) will be

recorded together • Lecture 2 (2-00pm to 3-00pm) will be recorded

separately A the beginning of each lecture, please:

– turn off your camera – mute your microphone

12

We’ll have a 5 minute break between the two morning lectures (1a and 1b)

Breaks

13

E-Housekeeping – Tutorials

• Tutorials WILL NOT be recorded.

About Me

15

My Bike

Anyone know where we are?

16

My instruments

17

My qualifications…

BSc (Hons) – Psychology

PhD – Psychology/Human

Factors

18

My Research – Transport Safety

• Road user behavior, performance and safety

• Vehicle technology design and evaluation

• Road and traffic engineering design and evaluation

19

My Publications

• Around 350 documents

• 250+ published; 180 peer-reviewed

• Citations: around 6,000+ • (Google Scholar)

• ..and 4 books

20

More about me…

https://www.engineering.unsw.edu.au/civil- engineering/staff/michael-regan

21

What about you?

How many of you want to be a road and traffic engineers?

22

Any housekeeping questions?

Course Details

24

Course Details

Faculty of Engineering School of Civil and Environmental Engineering Course Code: CVEN4405 Units of Credit: 6 Career: Undergraduate Level: 4 Offering: T3 2020

25

Course Aim

Faculty of Engineering School of Civil and Environmental Engineering

“To introduce students to fundamental Human Factors theory, principles methods and data and their application to road and

traffic engineering design, in order to optimise human well-being and overall performance of the road and traffic management

system.”

26

Learning Outcomes

CLO1: Explain the fundamental principles of HF that can be used by civil and transport engineers to facilitate user- centred design

CLO2: Apply HF principles, methods and data to the design of road and traffic management systems

CLO3: Plan for the integration of HF into the design lifecycle of the road and traffic management system

27

Lectures Timetable

Day Time Room/Building Wednesdays 11-00am – 1-00pm Online (AEST)

2-00pm – 3-00pm Online (AEST) No lectures in Week 6

28

Tutorials - Timetable

Tutor: Mitchell Cunningham Email: [email protected]

NB You only need to attend one of the tutorials on Thursdays

Day Time Room/Building Thursdays 2-00pm – 4-00pm Online (AEST)

4-00pm – 6-00pm Online (AEST)

No tutorials in Week 6

29

Lecture and Tutorial Content

The content of the lectures and tutorials is described in the Course Outline

Your demonstrator, Mitch Cunningham, will take you through the Course Outline in more detail during your Wk1 tutorial.

Weeks 1 to 3 lectures focus on fundamental Human Factors knowledge for human-centred design across many Civil Engineering disciplines

Remaining lectures focus specifically on Human Factors in Road and Traffic Engineering.

Tutorials focus on consolidating and practically applying the knowledge from lectures.

Human Factors

31

Who has ever heard of the term “Human Factors”

What do you think it means?

Human Factors

32

Video: What is Human Factors? (3:27)

Source: https://www.youtube.com/watch?v=m4f81ZS19v8

33

Human Factors: Definition

Human Factors is the scientific discipline concerned with: • understanding the interactions among humans and other

elements of a system, and

• the profession that applies theory, principles, data, and methods to design in order to optimise human well-being and system performance.

• The terms ergonomics and human factors are often used interchangeably

Source: IEA; AS7470; Sanders and McCormick 1987

34

Human-Centred Design

Human Factors puts the human as the centre of attention in system development.

“Systems cannot be considered to be truly integrated without the appropriate matching of users (not forgetting maintainers), the technology or equipment they will use, and the environment within which the equipment will be operated”

This is human-centred design.

Source: Sandom & Roger (2004), p. 4

35

Conventional Thinking vs Systems Thinking

Conventional Thinking Systems Thinking

Systems and equipment are designed for technical reasons, i.e., "they have to be that way”

Systems and equipment should be designed for their users

The person is responsible for any errors made in use of equipment

Characteristics of the work and work system predispose to making errors

Invokes the concept of the accident- prone person

Invokes the concept of the accident- prone situation

Strategies to reduce error: • better personnel selection • increase/improve training • increase motivation

Strategies to reduce error: • analyse task & system demands • design equipment to suit user

capabilities & limitations

36

Human Factors: Benefits

• Discussion: What do you think might be some of the benefits of highly usable systems?

– For example, a highly usable transport system?

37

Human Factors: Benefits (2)

Highly usable systems are: • “easier to understand and use, thus reducing training and

support costs; • improve user satisfaction and reduce discomfort and stress; • improve user productivity and operational efficiency of

organisations • improve product quality and provide a competitive

advantage.”

Source: Sandom & Roger (2004), p. 5

38

4 Key Principles For The Human-centred Approach To Design

There are 4 key principles for the human-centred approach to design that underpin the foundations of Human Factors:

1. “encourage the active involvement of users in design, and clearly understand the user and task requirements;

2. establish the appropriate allocation of functions between users and technology;

3. iterate design solutions; 4. adopt a multi-disciplinary approach to system design.”

Source: Sandom & Roger (2004), p. 4

39

Human Factors: Short History

Human Factors was really born out of WW2

During WW2, the major role of behavioural scientists was on: • The design of tests for selecting the right people for

specialist jobs e.g. for selecting pilots

• The design of improved training procedures for specialist jobs

Source: Sanders & McCormick (1987)

40

Human Factors: Short History (2)

But was soon realised that, even with the best selection and training, operation of some complex equipment exceeded capabilities of people that had to use it.

• e.g. over a 2-year period, 2,000 U.S Air Force planes were in accidents because the flap and landing gear levers were identical in appearance and located side by side: - look and placement of them caused confusion, especially among trainee pilots.

Source: Sanders & McCormick (1987)

41

Human Factors: Short History (3)

“It was time to start fitting the equipment to the person rather than fitting the person to the equipment.”

That was the beginning of Human Factors, or Ergonomics

Source: Sanders & McCormick (1987)

42

Human Factors: Scope

The scope of Human Factors is very broad, but can be divided into 3 main domains (based on IEA):

Source: Adapted from IEA

Physical Factors

Cognitive Factors

Organisational Factors

43

Human Factors: Cognitive

The cognitive side of Human Factors is concerned with psychological capabilities and limitations of human performance:

• Human information processing – i.e. the mental processes involved in performing an activity (e.g., sensation, perception, attention, memory, decision making and responding)

• Factors that influence information processing that can degrade human performance (e.g. age, experience, workload, fatigue, drugs, alcohol) and lead to human error.

Source: Watson, (2002)

44

Human Factors: Physical

The physical side of Human Factors focuses on the physical capabilities and limitations of human performance and can be broken down into 3 sub-areas:

1. Anthropometry (Anthropos fr. Greek = human) • the science of measurement of human body shapes and sizes

2. Physiology • the science of normal bodily functions

3. Biomechanics • the science of mechanical properties of the structure and

movement of the human body.

Source: Watson, (2002)

45

Human Factors: Physical (2)

The physical side of Human Factors is also concerned with environmental factors that influence human performance, such as:

• Sound • Lighting • Noise • Motion (vibration, acceleration, weightlessness)

and how knowledge of these factors can be applied to the design and operation of tasks, equipment and systems.

46

Human Factors: Organisational

Most humans work with other people and technologies within a socio-technical system of some kind (e.g. transport)

Organisational Human Factors is concerned with optimizing the design and operation of the sociotechnical environment in which people work.

This area of Human Factors is concerned with organisational structures, communication, working hours (e.g. shift work), organizational culture and teamwork.

Source: Watson, (2002)

47

Questions ?

Over to ….

48

Readings:

Read Chapter 1 of the following text (a short introduction to Human Factors) in your own time. There is no time limit.

• Sandom, C. & Roger, S. (2004). Human Factors for Engineers. Stevenage, UK: The Institution of Engineering and Technology (IET)

You can access the book via the Leganto link on the Moodle page for CVEN 4405

Prof. Michael Regan, PhD Research Centre for Integrated Transport Innovation

(rCITI) Room 112, Civil Engineering Building (H20)

E: [email protected]

50

5 minutes

Lecture Break

CVEN4405: Human Factors in Civil and Transport Engineering

Human Performance Limitations 1: Human Information Processing,

Nervous System, Vision and Hearing

Week 1, Lecture 1b

52

Welcome Back!

53

Lecture Recording

PLEASE NOTE.

This lecture is being recorded.

Participation in this meeting indicates your consent to be included in the meeting recording.

54

Your Course Coordinator and Lecturer

Prof. Michael Regan, PhD Professor of Human Factors

Research Centre for Integrated Transport Innovation (rCITI) School of Civil and Environmental Engineering

UNSW Sydney

E: [email protected] Staff Webpage

55

The CVEN 4405 Teaching Team

Coordinator and Lecturer Prof. Michael Regan Professor of Human Factors Research Centre for Integrated Transport, UNSW Sydney E: [email protected]

Teaching Fellow Dr Prasannah Prabhakharan Research Fellow Research Centre for Integrated Transport, UNSW Sydney E: [email protected]

Demonstrator Mitch Cunningham E:[email protected]. au

56

Last Lecture - Recap

• Me • Course details • Human factors – definition • Human Factors - benefits • Human Factors – short history • Human Factors – scope • Thursday Tutorial • Questions? • Readings

57

Lecture 1b - Overview

• Human Information Processing • Nervous system and sensation • Visual System • Auditory system • Questions? • Thursday Tutorial • Readings

58

Learning Outcomes

CLO1: Explain the fundamental principles of HF that can be used by civil and transport engineers to facilitate user- centred design

CLO2: Apply HF principles, methods and data to the design of road and traffic management systems

CLO3: Plan for the integration of HF into the design lifecycle of the road and traffic management system

59

Human Information Processing (1)

• In the last lecture we talked about the 3 main areas of Human Factors – Cognitive, Physical and Organisational.

• In this course, we will focus mainly on the Cognitive and Physical sides of Human Factors, as these are most relevant to Civil and Transport Engineering.

• In the first lecture, we learnt that the Cognitive side of Human Factors is concerned mainly with understanding the psychological capabilities and limitations of humans, and how an understanding of these can be used for user-centred design.

60

Human Information Processing (2)

• Human Information Processing is a term that describes the various mental processes that are assumed to occur in the human brain when we perform an activity – from the time we sense information (e.g. see a traffic signal change from red to green), to the time we respond to the information (e.g. press the accelerator pedal to move forward).

• The end product of these mental processes is what we call “performance. “

61

Wickens’ Model of Human Information Processing - Introduction

• Understanding these mental processes helps us to identify the capabilities and limitations of human performance we need to consider when we design things for human use – in our case, the road and traffic management system.

• One model of Human Information Processing that is often used for design in the field of Human Factors is a model by Christopher Wickens (1992)…..(see following slide)

62

Wickens’ Model of Human Information Processing - Figure

Source: Adapted from Wickens (1992), p. 17

63

Wickens’ Model of Human – The Model (2)

• Wickens’ model allows you to break up human information processing into discrete stages; but it is an oversimplification of how the complex brain actually works.

• It is a useful model to keep in your mind as a design heuristic as we go through this course.

64

The Nervous System – at a Glance

When a driver responds to a red traffic light that turns green and hits the accelerator pedal, a number of processes occur:

• The sensory receptors (sense organs) receive stimuli, in the form of energy, from the environment (e.g. light energy from the green traffic light)

• The nerves convert this energy into electrical impulses which are carried from the sense organs to higher areas of the brain responsible for perception and decision making

• The information is then sent from the brain to the muscles, which control the action of the bones, joints and tendons

• Nervous impulses travel at a speed varying between 0.6 and 20m/sec, depending on thickness of the tissue (myelin sheath) around the nerve fibre and some other factors

Source: Oborne (1987, pp. 15-16)

65

Sensory Receptors (1)

Stimuli enter the Sensory Processing box in Wicken’s model through sensory receptors.

There are 3 types of sensory receptors: 1. Exteroceptors – they receive information about the world

outside the body, and include the eyes, ears, nose, taste buds and touch receptors in the skin.

2. Interoceptors – receive information about the world inside the body, such as the state of hunger or fullness of the bladder.

3. Proprioceptors – provide information about the position of the body, or parts of it, in space. These include kinaesthetic receptors in the muscles and tendons, and the vestibular receptors in the ears which informs the person about their orientation in space

Source: Oborne (1987, pp. 16-17).

66

Sensory Receptors (2)

• Discussion: think of the last time you walked up the stairs. Which receptors allowed you to walk up them without looking?

• Discussion: think of the last time you were in a plane, with your eyes closed, and could sense that the plane was turning right or left. Which receptors allowed you to sense that?

Source: Oborne (1987, pp. 16-17).

The Visual System

68

The Visual System

The visual system is the system most overloaded when people drive and when they work.

It consists of the two eyes connected to the visual cortex area of the brain by an optic nerve, which allows for binocular vision.

The eye is like a camera: » Light enters the eye through the pupil » The iris controls the diameter of the pupil, regulating the

amount of light that enters the eye » Light is then focused by the lens onto the retina – which

contains receptor cells called rods and cones

Source: Oborne (1987, pp. 18-19).

69

The Eye - Diagram

Source: Google Images

70

The Photoreceptors - Cones and Rods

Source: Adapted from Oborne (1987, pp. 19)

Rods Cones Mostly in periphery of retina Mostly in centre of retina

Function in low light, used mostly for night vision

Function in bright light, and used for normal vision (daytime)

Differentiate between shades of black/white

Differentiate between colours

Sensitive to greenish part of spectrum Sensitive to yellowish part of spectrum

Sensitive only to very weak stimuli Mainly involved in visual acuity and movement perception

NB We can see better at night if we look off centre, like astronomers

NB For maximum perception, visual information should be presented centrally to the eye, rather than peripherally, where cones are located.

71

Dark and Light Adaptation

Rods and cones allow eye to function efficiently over wide range of illumination levels

Rods take over in low light; and vice versa. Adaptation occurs when they swap over

If illumination change is slow, no problem. If it is fast, the swap over is not fast enough and temporary blindness can occur (e.g. pitch darkness to bright sunlight)

• In this case, must close eyes or reach for sunglasses

Cones can adapt to bright light quickly – a minute or two. Rods take much longer – up to 30 mins or more.

Source: Oborne (1987, pp. 16-17)

72

Dark and Light Adaptation – Design Implications

Dark/coloured goggles have to be worn by some workers (e.g. miners, radar operators) who work in dark environments for a while before starting work

• Discussion: Can you think of a piece of road infrastructure where dark adaption might be an issue? Why? How can we manage the problem?

Source: Oborne (1987, p 20)

73

Visual Movement Perception

We perceive movement in 2 ways:

1. By moving our eyes to receive information about an object’s speed and direction

2. By the object’s image moving across the retina; movement is perceived by the cones, at a minimum velocity of about 1-2 minutes of arc/sec.

At faster speeds, object is automatically tracked by the eyes

Source: Oborne (1987, p 20).

74

Visual Spatial Perception

We use binocular and monocular vision to judge spatial relationships between objects

Binocular vision – the two images received by the brain are compared, and the disparity between them is used to calculate their relative positions

Monocular vision – we use monocular cues also, based on past visual experiences, including the relative sizes of objects, and shadow (if one object casts a shadow).

Source: Oborne (1987, p 21)

75

Visual Acuity - Defined

Visual acuity is the process by which we can see fine detail, and many aspects of work and driving require this ability.

• Discussion: What objects in the road environment require us to see fine detail?

There are 3 types of visual acuity: 1. Line acuity - ability to see fine lines of known thickness 2. Space acuity - ability to see that two spots or lines are separated

by a space 3. Vernier acuity - ability to detect discontinuity in a line when one

part of it is slightly displaced

Source: Oborne (1987, p 22)

76

Visual Acuity – Factors Determining Degree of Visual Acuity (1)

1. Size of the pupil: • it needs to be open • size of pupil is linearly related to visual acuity down to 1 mm • High illumination levels and some drugs (e.g. alcohol) may constrict

pupil, compromising ability to see fine detail

2. Luminance of object • that is, the light intensity reflected from object: • objects too fine to be seen in low illumination may be clearly visible at

higher levels of illumination • If illumination too high, pupil constricts, reducing acuity

Source: Oborne (1987, p 22)

77

Visual Acuity – Factors Determining Degree of Visual Acuity (2) 3. Exposure time

• reduced exposure time reduces visual acuity. • need at least 200 ms of exposure time at normal daily

levels of illumination

Source: Oborne (1987, p 22)

78

Age and Visual Performance (1)

Our visual functions start deteriorating when we are quite young – at age X; can you guess X?

1. Less light reaches the retina: The amount of light reaching retina of a 60 year old person is 1/3 the

amount reaching retina of a 20 year old person - because of yellowing of lens:

• Therefore, older people need more illumination to perform visually as well as younger people

• We need to design visual tasks carefully to take this into account, especially in an aging population

Source: Oborne (1987, p 23)

79

Age and Visual Performance (2)

2. Accommodation ability deteriorates: • Accommodation is the ability to focus the eyes on objects at different

distances • Accommodation is performed by the ciliary muscles in the eye -

contracting and changing shape of the lens • The function of these muscles deteriorates with age • The “near point” at which eyes can sharply focus moves further away

from the eye (causing long-sightedness; and the need for reading glasses).

• The speed of accommodation also decreases with age – e.g. ability to focus between computer screen and a book if typing text from book into computer.

• Spectacles can help

Source: Oborne (1987, p 23)

80

Visual Flicker

Sometimes human operators need to respond to visual stimuli that flicker - e.g. flashing lights - to catch their attention

There is a certain flash frequency, however, at which separate flashes appear to merge, and seem to turn into steady- state illumination

This is called the critical fusion frequency (cff). It ranges from 2-3 flashes/sec at very low illumination levels to

60 flashes/sec with very high levels of illumination

• Discussion: What do you think the implication of this for design?

Source: Oborne (1987, p 23)

81

Colour Vision (1)

Colour is important in road and traffic design, and other working environments

Is used to help drivers, for example, distinguish between traffic signals (green, amber, red) and to code traffic signs (e.g. red Give Way signs).

We perceive different colours (or hues) as a result of the eyes receiving different wavelengths of light – between 440 and 700 nanometres

Source: Oborne (1987, p 25)

82

Colour Vision (2)

Shorter wavelengths – around 450nm – are blue; and longer wavelengths – around 650nm – are red.

The quality of the colour is a function of the luminance of the wavelengths in the light and the saturation (amount of white light perceived).

Source: Oborne (1987, p 25)

83

Colour Vision - Colour Adaptation

Sometimes, colour sensations seem different from what they are due to colour adaptation and colour constancy.

Colour adaptation – occurs when some colour sensations are altered by continuous exposure to others

• e.g. looking at a bright yellow stimulus for a few minutes, and them a red one, will cause the yellow one to turn XXXX

• LET’S TRY IT! (next 3 slides)

Source: Oborne (1987, p 25)

84

Colour Adaptation - Demo

85

Colour Adaptation - Demo

86

Colour Adaptation - Demo

87

Colour Vision - Colour Constancy

Colour constancy - is a psychological mechanism which makes us see the same colour even under changing conditions of illumination.

e.g. a yellow banana appears yellow whether it seen in semi- darkness or in bright sunlight outdoors.

e.g. This locomotive.. There isn’t one red pixel in the entire image.

Source: Oborne (1987, p 25); Copyright Akiyoshi Kitaoka 2020 (January 13)

88

Colour Vision - Colour Deficiencies (1)

Very few people are “colour blind” i.e. blind to colour (about 0.003%) – they see black, white and shades of grey

But some people are colour “deficient” – around 6.0% of males and 0.5 % of females

This is a problem if colour is used to code information.

• Discussion: Can you think of examples where colour coding could cause problems for these people? How can we use design to help them overcome this problem?

Source: Oborne (1987, p 25)

89

Colour Vision - Colour Deficiencies (2)

Colour-deficiencies can be functionally classified in 3 ways:

Normal Vision Protanopia & Deuteranopia: Red/Green Blindness

Tritanopia: Yellow/Blue Blindness Monochromacy: Total Colour Blindness

90

Have you tested yourself? Let’s try (through Ishihara test) • One of the most well-known color blindness test

Colour Vision - Colour Deficiencies (2)

91

Colour Vision - Colour Deficiencies (2)

92

Colour Vision - Colour Deficiencies (2)

93

Colour Vision - Colour Deficiencies (2)

The Auditory System

95

The Auditory System (1)

The ear has three sections: 1. the outer ear 2. middle ear and 3. inner ear

• Sound pressure waves enter the outer ear and travel through a narrow tube, called the ear canal, which leads to the eardrum.

• The sound waves cause the eardrum to vibrate.

• Sound vibrations then move through the ossicles (3 small bones) to the cochlea.

• Sound vibrations then cause fluid in the cochlea to move.

• This fluid movement causes the hair cells in the cochlea to bend.

• The bending of hair cells creates neural signals which are then received by the auditory nerve

Source: https://www.medel.com/us/how-hearing-works/

96

The Auditory System (2)

Hair cells that are bent at one end of the cochlea send low pitch sound information; hair cells at the other end send high pitch sound information.

Loudness depends on how much the hairs are bent.

Finally, the auditory nerve sends neural signals to the brain where they are interpreted as sounds.

Source: https://www.medel.com/us/how-hearing-works/

97

The Ear - Diagram

Source: Google Images; similar to in Oborne, (1987, p. 27)

98

Sound Localisation

Having two ears helps us localise sound – to determine where it’s coming from

Being able to localise sound – e.g. the sound of danger – is an important survival mechanism

Sound localisation is made possible by: • Time differences in when sound reaches each ear • Intensity differences in the sounds that reach each ear (because of

shadowing of the head) • Head movement – which further increases location accuracy

• Discussion: In what situations is sound localisation important in the road environment?

Source: Oborne (1987, p. 28)

99

Tone and Loudness Discrimination (1)

Humans are limited in their ability to discriminate between, and hence act on, different sounds.

There are two types of sound discrimination processes:

1. Relative judgements – e.g. when comparing two sounds in terms of their loudness

2. Absolute judgements – e.g. in which the person has to judge the exact pitch of a sound

• People are better at making relative judgements than absolute judgements.

• But the ability of people to make relative judgements is limited –they can discriminate between only about 4 to 5 sounds of different loudness and about 4 to 5 sounds of different tones.

Source: Oborne (1987, p. 29)

100

Tone and Loudness Discrimination (2)

We can discriminate better between sounds, though, if the different dimensions of sounds are combined:

e.g. if we ask people to discriminate between sounds, each having different frequencies, intensities, durations, etc

In this case, can discriminate between around 150 separate tones without error.

Source: Oborne (1987, p. 30)

101

Questions?

Over to ….

102

References

• Oborne (1987). Ergonomics at Work (2nd Edition). Liverpool, UK: John Wiley and Sons (Chapter 2)

• Wickens, C.D. (1992). Engineering Psychology and Human Performance (2nd Edition). USA: Harper Collins (Chapter 1)

Prof. Michael Regan, PhD Research Centre for Integrated Transport Innovation

(rCITI) Room 112, Civil Engineering Building (H20)

E: [email protected]

104

CVEN 4405 Human Factors in Civil and Transport Engineering

Term 3 2020 Week 1 - Lecture 2

PRESS RECORD BUTTON

+

SHARE SCREEN

+

PRESS AUDIO BUTTON

105

Lecture Recordings

PLEASE NOTE.

This lecture is being recorded.

Participation in this meeting indicates your consent to be included in the meeting recording.

CVEN4405: Human Factors in Civil and Transport Engineering

Human Performance Limitations 2:

Perception and Attention

Week 1, Lecture 2

107

Lecture Recording

PLEASE NOTE.

This lecture is being recorded.

Participation in the meeting indicates your consent to be included in the meeting recording.

108

Welcome Back!

109

Course Coordinator and Lecturer

Prof. Michael Regan, PhD Professor of Human Factors

Research Centre for Integrated Transport Innovation (rCITI) School of Civil and Environmental Engineering

University of NSW Sydney

T: +61 (0)2 9385 9504 E: [email protected]

Staff Webpage

110

Last Lecture - Recap

• Human Information Processing • Nervous system and sensation • Visual System • Auditory system • Questions? • Readings

111

Lecture 1c - Overview

• Perception • Perceptual Countermeasures • Attention • Types of Attention • Design guidelines for attention • Questions? • Reading • Thursday Tutorial

112

Learning Outcomes

CLO1: Explain the fundamental principles of HF that can be used by civil and transport engineers to facilitate user- centred design

CLO2: Apply HF principles, methods and data to the design of road and traffic management systems

CLO3: Plan for the integration of HF into the design lifecycle of the road and traffic management system

Perception

114

Perception

In this lecture, we’ll move to the next stage of processing in Wickens’ model of human information processing:

Perception

115

Wickens’ Model of Human Information Processing - Perception

Source: Adapted from Wickens (1992), p. 17

116

Perception (2)

• Discussion: what do you think “Perception” means? • What does it mean when we say we perceive something?

117

Perception (3)

Once information has been sensed, higher centres in the brain interpret and attach meaning to it.

This is the process of perception, and is the next stage of processing in Wickens’ model.

The same sensory information can give rise to different perceptions in different people

118

Perception - Visual Illusions

Source: Google Images - My Wife and My Mother-In-Law

119

Perception - Visual Illusions

Source: Google Images – Vase or Two Faces

120

Perception (4)

The same sensory information can give rise to different perceptions in different people.

So, if you want all people (e.g. drivers) to extract the same meaning from traffic management devices such as signs, the displayed information should be unambiguous.

Ideally, you should conduct an evaluation to determine whether the information being displayed is clearly comprehended by a small sample of the population they are intended for (e.g. drivers).

121

Perception (5)

Our perceptions are heavily influenced by past experience, learned associations, expectations and training e.g.

• Shapes of road signs (e.g. stop signs) • Colour of traffic signals (green = go)

Here are some more….

Source: Sanders & McCormick (1987), p. 84

122

Perception (6)

Source: Google Images

123

Perception (7)

To ensure correct perception, the design of displays should meet 2 objectives:

1. The display must be able to be clearly seen/heard 2. The design should help the viewer (e.g. driver) correctly perceive

the meaning of the display

For displays designed for specific traffic environments, adequate training of drivers to interpret the meaning of the displays is necessary.

• Can you think of some examples?

Source: Sanders & McCormick (1987), p. 85

124

Perception (8)

The design should make the most of design features that help people to correctly perceive the meaning of the display.

• Discussion: Do you think this has been achieved in the following examples?

Source: Sanders & McCormick (1987), p. 85

125

Perception (7)

Source: Google Images

126

E.g. Form 1 Lane

Have you seen these words painted on the road?

• Discussion: What’s the best order in which to present them to perceive their meaning correctly? Why?

OR

Source: Google Images

FORM ONE

LANE

LANE ONE

FORM

127

Perception - Visual Illusions

Our perceptions can also be distorted.

Which line is longer – the top one or the bottom one? • Müller-Lyer Illusion

Source: Google Images

128

Perception - Visual Illusions

Which orange circle is larger – the left one or the right one? • Ebbinghaus Illusion

Source: Google Images

129

Perception - Visual Illusions

Which line is longer – the top one or the bottom one? • Ponzo Illusion

Source: Google Images

130

Perception – Perceptual Countermeasures

Our perceptions can be distorted deliberately by designers to influence our behaviours.

• See next 2 slides

131

Distorted Perceptions – 2D Perceptual Countermeasures

This is an example of what traffic engineers call “2D perceptual countermeasures”

Source: Google Images

132

Distorted Perceptions – 3D Perceptual Countermeasures

This is an example of what traffic engineers call “3D perceptual countermeasures”.

• Discussion: What are they trying to achieve?

133

Distorted Perceptions – 3D Perceptual Countermeasures

Discussion: What do you think the traffic engineers were trying to achieve with this 3D perceptual countermeasure?

Attention

135

Wickens’ Model of Human Information Processing - Attention

Source: Adapted from Wickens (1992), p. 17

136

Attention (1)

The next stage of information processing in Wickens’ model is “Attention”.

It is shown in the circle at the top of Wickens’ model.

Source: Adapted from Wickens (1992), p. 17

137

Attention (2)

“We often talk about “paying attention”. Children never seem to do it, and we occasionally do it to the wrong thing and miss something important.

These sorts of everyday experiences suggest that attention can somehow be directed to objects activities, and that things we are not paying attention to are often not perceived (or at least recalled).”

Source: Sanders & McCormick (1987), p. 64

138

Types of Attention

Attention is the name given to the mental process which governs which material enters awareness and which does not.

Attention is necessary in order to transfer information from sensory storage through to Working Memory, and to hold it in working memory.

There are 3 main types of attention: 1. Selective Attention 2. Focused Attention 3. Divided Attention

Source: Sanders & McCormick (1987), p. 64

139

Selective Attention

Selective attention occurs when “…a person has to monitor several sources of information to determine whether a particular event has occurred”

e.g. a pilot scanning instruments looking for an abnormal reading (e.g. low fuel)

e.g. a driver scanning the freeway environment looking for the next exit

Try this selective attention test…….

Source: Sanders & McCormick (1987), p. 64

140

Selective Attention…. looking out for events

141

Focussed Attention

• Focused attention occurs when a person must attend to one source of information in the face of many potential sources of distraction.

• Discussion: Can you think of some examples of focussed attention?

Source: Wickens & McCarley (2008)

142

Focussed Attention (Examples)

e.g. when you try to read a book when someone is on the telephone

e.g. when you try to listen to a person in a noisy restaurant

e.g. when you try to read information on a road sign that is full of unnecessary clutter

143

Divided Attention (1)

• Divided attention occurs when a person must attend to more than one task at a time.

• This is usually accomplished by timesharing – alternating attention between the tasks.

• Humans have a limited capacity to process information – so when two or more tasks have to be performed at the same time, this capacity can be exceeded

• If this occurs, the performance of at least one of the tasks will deteriorate.

144

Divided Attention (2)

It is possible, however, two perform some tasks as well together as separately – in parallel – in some situations.

• How about this!! Look what a drummer can do? – Can anyone else do it?

Now try this – move right leg in circular motions clockwise and write number 6 with right hand in the air.

• Now try, moving right leg in circular motions anti-clockwise

145

YouTube video – Varieties of Attention

• https://www.youtube.com/watch?v=s4JBqLoY3tY

A link to this video has been posted on Moodle as a supplementary video for you to watch in your own

time.

Look under the following heading: “Lecture and Tutorial Content”

Source: https://www.youtube.com/watch?v=s4JBqLoY3tY

146

Selective Attention – Design Guidelines (1)

1. Where multiple channels of information have to be scanned to determine whether a particular event has occurred, use as few channels as possible, even if it means increasing the signal rate per channel

• E.g. if a person in a control room has to detect 25 abnormal readings per minute, present them on one display rather than, say, 5 displays, each presenting only 5 abnormal readings per minute.

Source: Sanders & McCormick (1987), p. 65

147

Selective Attention – Design Guidelines (1)

2. Provide information to the person as to the relative importance of the various information channels, so attention can be directed more effectively.

– E.g. explaining to a young driver the most important hazards to look out for while driving

Source: Sanders & McCormick (1987), p. 65

148

Selective Attention – Design Guidelines (2)

3. Reduce the overall level of stress on the person, so that more channels will be sampled - because, as the number of channels of information (e.g. number of signals) that have to be monitored increases, human performance declines.

• E.g. reduce the amount of sign clutter in the road environment, so that more traffic-relevant information is sampled.

Source: Sanders & McCormick (1987), p. 65

149

Selective Attention – Design Guidelines (3)

4. Provide the person with some preview information as to where signals will occur in the future – to help direct their attention to the right direction.

• E.g. a warning sign telling drivers that there is a railway level crossing up ahead.

Source: Sanders & McCormick (1987), p. 65

150

Selective Attention – Design Guidelines (4)

5. Train the person in how to effectively scan information channels so they develop optimal scanning patterns

• E.g. pilots; control room operators; young drivers

Human Factors is not just about user-centred design. • It is also about selecting people with aptitudes and

skills that match what is required to perform a task (e.g. to fly a plane) and

• training them in how to fly the plane. The main focus of Human Factors, is on human-centred

design. Source: Sanders & McCormick (1987), p. 65

151

Selective Attention – Design Guidelines (5)

6. If multiple visual channels have to be scanned, put them close together to reduce scanning requirements

• E.g. signal lanterns on traffic lights (green, amber and red) are positioned close together

7. If multiple auditory channels are to be scanned, be sure they don’t mask one another

• E.g. if there are multiple collision warnings that could go off in a car at the same time, make sure that no two of them sound exactly the same.

Source: Sanders & McCormick (1987), p. 65

152

Focussed Attention – Design Guidelines (1)

Focused attention, as discussed, occurs when a person must attend to one source of information in the face of many potential sources of distraction.

The following are some general design guidelines for encouraging focussed attention:

1. Make the competing information channels as distinct as possible from the channel to which the person must attend.

• E.g. in a cluttered traffic road environment, make sure that the clutter is as distinct as possible from the sign you drivers to focus on (e.g. smaller, different colour etc)

Source: Wickens & McCarley, (2008); Sanders & McCormick (1987), p. 66

153

Focussed Attention – Design Guidelines (2)

2. Separate, in physical space, the competing channels of information channels from the channel of interest; by at least 1 degree of visual angle

• E.g. Do you think they did?

Source: Sanders & McCormick (1987), p. 66

154

Focussed Attention – Design Guidelines (3)

3. Reduce the number of competing channels of information • How many competing channels of information can you spot

here?

Source: Sanders & McCormick (1987), p. 61

155

Focussed Attention – Design Guidelines (4)

4. Make the channel of interest larger, brighter, louder or more centrally located than the competing channels

• E.g.

156

Divided Attention – Design Guidelines (1)

Remember - Divided attention occurs when “…two or more separate tasks must be performed simultaneously, and attention must be paid to both”

There are some guidelines that can be used to improve human performance when people are in divided attention situations.

Source: Sanders & McCormick (1987), p. 64

157

Design Guidelines for Divided Attention (1)

1. Where possible, minimise the number of potential sources of information that people need to pay attention to.

2. If dividing attention between two or more sources of information that are likely to stress a person’s limited attentional capacity, provide the person with information about the relative priorities of the tasks, so that an optimum strategy of dividing attention can be created.

• E.g. young drivers focusing ahead instead of in periphery

Source: Sanders & McCormick (1987), p. 67

158

Design Guidelines for Divided Attention (2)

3. Keep the difficulty of the tasks as low as possible. 4. Design the tasks to be as dissimilar as possible in terms of

their demands on processing stages, input and output modalities, and processing codes

5. When manual tasks have to be timeshared with sensory or memory tasks, the greater the learning of the manual tasks, the less interference it will create with sensory and memory tasks.

• e.g. the more the young driver learns how to manually control the vehicle, the more automated it will become, leaving more attention available to detect and respond to hazards.

Source: Sanders & McCormick (1987), p. 67

159

Questions ?

Over to ….

Prof. Michael Regan, PhD Research Centre for Integrated Transport Innovation

(rCITI) Room 112, Civil Engineering Building (H20)

E: [email protected]