HUMAN FACTORS HCI AND HUMAN-CENTERED DESIGN - 1

1-INTRODUCTION OF HUMAN FACTORS HCI AND HUMAN-CENTERED DESIGN

1.0 Introduce

P.L.Patrick Rau Ph.D

Professor,Director

Institute of Human Factors & Ergonomics

Department of Industrial Engineering

Tsinghua University

1.1 Early History of Human Factors / Ergonomics

• Human Factors = Engineering + Science + Social & humanity sciences
• 1713 Ramzzini “diseases of workers”
• Because after Industrial Revolution technologies change people’s lives. 

• 1857 about 160 years ago “ergonomics” = “Human Factors” :The term “Ergonomics” was firstly introduced.
• ergon -> work/activeties
• nomos -> order/law/control
• ergon+nomos = law of work / order of activities
• Frank and Lilian Gilbreth and their children ( She has 12 kids! ) 

• The book describe how to apply the interest in motion and time study to the organisation and activities
• motion + time study -> organisation + activities
• The teacher learn “Human Factors” at Purdue University 

• Professor Gilbreth is teacher’s teacher
• Lillian Gilbreth had been lecturing at Purdue University since 1925
• Before World War 2 , The main focus on human of factors is to fit people into the work by selecting and training. 

• After world war 2, Fit the work to the people.

• since 1960s (job’s era computer industry) different industries began to recognise the importance of human factors on design the products for consumers including information and communication technology.
• IT Industry learned a lot from human factors.
• In 1980s, bad things happened.
• One is the incident in Three Mile Island unclear power plant in the US
• The other is explosion and fire at the Chernobyl nuclear power plant in former Soviet Union 

• Both relating human, error is human
• Human Factors help us 
• Aviation safety
• Medical devices
• Design of products and facilities for the elderly : design environment, the procedure ,the system, the products for elderly people
• Back to 1930 The concept we called “engineering psychology”,first introduced in China. 

• Starting in about 1960s, some local researches and Studies have started.
• In 1989, the first ergonomics, academic society — China Ergonomics Society has established.

1.2 Physical Ergonomics

• Physical Ergonomics is a very important domain in Ergonomics
• Domains of specialisation : Physical Ergonomics

• human
• anthropometric
• physiological
• biomechanics characteristics

• anthropometric ex:
• The data in the Unite State, issued in 1989, about 25 years ago 
• Percentiles 50th(中位数) -> 1.755m (man) 1.628m (lady)  : means 50% people taller than this. 

• Why we need eye heigh ? 

• Different dimensions (size data) can help us 
• Chinese data issued 1989 by Chinese Standard Bureau. 
• percentiles 50th : 1.678m (man),1.578m (lady) so on and so forth ( 等等 )
• The group of 18-25 is taller.

• Relevant topics : work postures 

• The posture when study or using digital devices.
• materials handing
• repetitive movements
• work related repetitive injuries
• work place layout
• safety and health 
• Worry posture lead to some pain. ex:
• carpal tunnel syndrome  腕管综合症
• programmers elbow
• tennis elbow 

1.3 Ergonomics in Ancient China

• Song Dynasty (960-1279) 宋朝 “weak”

• The majority of the Song army was infantry because the Song, as an agricultural society, could recruit many infantry( soldiers fighting on foot 步兵) soldiers quickly and easily.
• The Song’s enemies were mainly nomadic people with strong cavalry. (ex:  Mongolians, Genghis Khan)

• To fight against cavalry, the Song had to design weapons, armour(metal covering 铠甲) and a strategy(a plan to achieve long term goal) for their infantry troops(骑兵).

Three Ergonomic standards of the Song dynasty :

• The height standard for the organisation and remuneration of soldieries
• The anthropometric (body size) standard for soldier recruitment and selection
• The weight standard for Song infantry armour 

• 960 Human model Fail because if it is intricate (complex)
• 960 — 1199 Sticks of Equal Length, they also used infantry armour to measure the body size of soldiers.

• The standard for Song infantry armour was originally published in 1044 in the year 1044 by the third Emperor of Song Dynasty — Ren zong 

• Ren zong order some scholars to edit a military cyclopaedia called “Wu Jing Zong Yao ” 

• This military encyclopaedia covers famous campaigns, military organisation, strategy, weaponry, etc.

• There are five parts of the Song infantry armour

• Helmet
• Neck covering
• Shoulder covering
• Chest covering
• Belly and thigh Covering 

• Year 1133, the 12th Emperor of Song Dynasty in Chinese history  

• National Standard 

• In 1134, an order was issued by the 12th emperor (Gao Zong) that regulated the upper limit for the weight of Song infantry armour and the weight of each part of the armour
• The armour was composed of one thousand eight hundred and twenty-five pieces of steel. Every piece of steel is weighted according to the standard.
• The total weight was from about twenty-seven to about thirty kilograms. The upper limit was about thirty kilograms.

• The upper limit was about 30 kilograms. 

1.4 Cognitive Ergonomics

• Cognitive Ergonomics is concerned with mental process
• Perception
• Memory
• Reasoning
• Motor response
• Relevant topics

• mental workload
• decision-making
• skilled performance
• human-computer interaction
• human reliability
• work stress and training

• Human Computer Interaction ->HCI

• HCI involves the design, implementation and evaluation of interactive system in the context of users’ task and work
• Human -> individual user, a group of users, or user in an organisation 
• Computer -> any technology ranging from PC, large-scale system, or an embedded system 
• Interaction -> any communication between a user and computer, directly or indirectly 

• Graphical User Interface (GUI)

• Windows + Icon + Menu + Pointing device
• Before GUI, we use a deck of card to interact with computer 

• Xerox PARC : Alto, 1973 

• Windows
• Pointing Device - Mouse
• keyboard
• Icons

1.5 Human Information Processing

• HCI(Human Computer Interaction)

• No general and unified theory for HCI
• A marriage of art and science into a successful whole

• Human Information Processing Model 

• HIPM describe how people perceive information, process information and making all the responses

• User see what we expect to see

• have difficulty focusing on more than one activity at a time
• easier to perceive a structured information
• easier to recognise than to recall

• Design Implications

• It is important to keep consistency throughout the UI to reduce the unexpected objects for users.
• To exploit prior knowledge, use metaphor to allow user to apply their prior knowledge and experience.

1.6 Organisational Ergonomics an Human-Centered Design

• Organisational Ergonomics is concerned with the optimisation of social technical systems, including their organisational structures, policies, and processes.
• Relevant topics : 

• Communication
• Crew resource management
• Work design
• Design of working times
• Team working
• Participatory design
• Cooperative work 
• Virtual organizations
• Quality management

• Human-Centered Design (HCD/UCD)

• Involves users through the design and development process
• Understanding user
• Understanding tasks
• Understanding the environment
• Main principles of human-cantered design (IOS 9241:11,1997)
• Active involvement of users 积极参与到用户中去
• An appropriate allocation ( distribute ) of function between user and system 给用户和系统适当的功能
• The iteration of design solution 反复的设计解决方案
• Multidisciplinary design teams. 多学科背景的团队

• Essential UCD activities

• Understanding and specify the context of use
• Specify the user and organisational requirements
• Produce design solutions (prototype)
• Evaluate designs with user

• Why HCD?

• Poor designs everyday
• Products are supposed to be marketed as user-friendly
• ICT products have to be designed with an understanding that people with specific tasks in mind will want to use them in a way that is seamless with respect to their everyday work.
• User need to know how to think in terms of the users’ tasks and how to translate that knowledge into a system
• It is not intuitive or easy to design consistent, robust systems that will cope with all manner of user carelessness
• User interface cannot be plugged in at the last mindsets
• Not just pretty, but should support that tasks that people actually want to do, and forgive the careless mistakes - consider how HCI fits into the design process 

• HCD = psychology + Ergonomics + Sociology + Computer sciences + Business + …