Please enable JavaScript.
Coggle requires JavaScript to display documents.
1.2 UNDERSTAND HUMAN INTERACTION (1.2.1-1.2.6), A ‘typical’ computer…
1.2 UNDERSTAND HUMAN INTERACTION
(1.2.1-1.2.6)
A ‘typical’ computer system :
1.2.1 Computer Technology Influences
The Nature Of Interaction And Style Of
The Interface:
Processing speed
Designers tend to assume fast processors, and make interfaces more and more complicated.
Moore’s law
Memory capacity
short term and long term
-Random access memory (RAM)
-Some non-volatile RAM used to store basic set-up information
long term
-magnetic disks
-optical disks
speed, capacity, compression
PDAs
Flash-Memory
formats, access
ASCII - 7-bit binary code for to each letter and character
UTF-8 - 8-bit encoding of 16 bit character set
RTF (rich text format) - text plus formatting and layout information
SGML (standardized generalised markup language) - documents regarded as structured objects
XML (extended markup language) - simpler version of SGML for web applications
Media
-Images
-Audio/Video
Virtual reality systems and 3D visualization
positioning in 3D space
moving and grasping
cockpit and virtual controls
steering wheels, knobs
the 3D mouse
six-degrees of movement: pitch, yaw
data glove
fibre optics used to detect finger position
VR helmets
detect head motion and possibly eye gaze
whole body tracking
-accelerometers strapped to limbs
seeing 3D (helmets and caves)
Input / output devices for interactive users
keyboards (QWERTY etc.)
-Text input device -allows rapid entryof text -can connected with cable and be wireless
chord keyboards, phone pads
use numeric keys with multiple presses
handwriting, speech
Text can be input into the computer, using a pen and a digesting tablet
-natural interaction
Technical problems:
capturing all useful information - stroke path, pressure, etc. in a natural manner
segmenting joined up writing into individual letters
interpreting individual letters
coping with different styles of handwriting
Speech Recognition
Improving rapidly
Most successful when:
single user – initial training and learns peculiarities
limited vocabulary systems
Problem - external noise interfering, large vocabularies
Physical devices
Sound
used for error indications.
confirmation of actions e.g. keyclick.
Touch, feel, smell
touch and feeling important
texture, smell, taste
Environment and bio-sensing
sensors all around us
car courtesy light – small switch on door
ultrasound detectors – security, washbasins
1.2.2 Model Of Interaction
Some concepts:
-Users want to achieve goals in some domain.
The execution evaluation cycle:
establishing the goal - task language; imprecise
forming the intention - specific
specifying the action sequence
executing the action
perceiving the system state
interpreting the system state
evaluating the system state with respect to the goals and intentions
1.2.3 The interaction framework in HCI
User - Input: (articulating a goal)
Input –System
System - Output (execution & evaluation)
Output - User (interpretation by user)
1.2.4 The role of ergonomics in interface design
Ergonomics
Human Factors
arrangement of controls
physical environment
health issues
use of colour
the arrangement of controls
-Control layout is important
-Controls can be and laid out in various ways
functional
sequential
frequency
The physical environment & health issues
Colour
Colour Vision
1.2.5 The various interface style
a. Command line interface
b. Menus
c. Natural language
d. WIMP interface: Windows, icon, menus and pointers.
e. Question/answer and query dialog
f. Form-fills and spreadsheet
g. Point-and-click interfaces
h. 3D interfaces
i. Web navigation
1.2.6 Use the interaction framework to analyze the interaction involved in using the various interface styles.
Interactivity is the defining feature of an interactive system, e.g. the interface semantics and closeness to real-time interaction (speech recognition, visualization, menu dynamics).
In older systems, order of interaction is pre-emptive. Newer systems still have some of these features, e.g. modal forms.
Of course all interaction occurs in some wider social and organizational context.
A ‘typical’ computer system :
screen, or monitor, on which there are windows
keyboard
mouse/trackpad
variations
desktop
laptop
PDA