1. Human Factors &
Ergonomics
2nd Meeting

2. Tujuan
1. Memahami proses penginderaan pada
manusia
2. Memahami prinsip perceptual
organization
3. Memahami tahapan informational
processing
4. Memahami penerapan informational
processing dengan keselamatan jalan

3. Human Factors &
Ergonomics
Sensation & Perception

4. H
F
E
interactions
among humans and other
elements of a system
- human abilities
- human limitations
- behavioral patterns,
etc
the design of person–machine systems
a system which involves an interaction between
people and other system components, such as
hardware, software, tasks, environments, and work
structures

5. Human factor model

6. Interaction involves a
continuous exchange of
information
Sensation &
perception
- How people sense & perceive
- The characteristics and limitations
of the human sensory and
perceptual systems

7. Sensori modalitities
 Vision
 Audition
 Olfaction
 Gustation
 Somasthesis
 Vestibular
system
+

8.  All sensory systems extract information
about four characteristics of stimulation:
 the sensory modality and submodalities (e.g.,
touch as opposed to pain)
 the stimulus intensity
 the duration of the stimulation
 its location

9. Receptors
Sensory transduction: the conversion of physical stimulus
energy into electrochemical energy in the nervous system
Neurons
Dendrites, axons, synapses
Brain
Stimulus

10. Primary sensory receiving areas of the cerebral cortex
(Proctor & Proctor, 2012)

11. Vision

12. Audition

13. Vestibular System and Sense
of Balance
 The vestibular system provides us with our
sense of balance. It contributes to the
perception of bodily motion and helps in
maintaining an upright posture and and the
position of the eyes when head movements
occur
 The sense organs for the vestibular system
are contained within a part of the inner ear
called the vestibule, which is a hollow region
of bone near the oval window.

14. Somatic Sensory System
 The somatic sensory system is composed
of four distinct modalities:
 Touch is the sensation elicited by mechanical
stimulation of the skin
 Proprioception is the sensation elicited by
mechanical displacements of the muscles and
joints
 Pain is elicited by stimuli of sufficient intensity
to damage tissue
 Thermal sensations are elicited by cool and
warm stimuli

15. Gustation
 The sensory receptors: taste buds
 They line the walls of bumps on the
tongue that are called papillae, as well as
being located in the throat, the roof of the
mouth, and inside the cheeks

16. Olfaction
 Receptor cells located in the olfactory
epithelium, a region of the nasal cavity
 An olfactory rod extends from each
receptor and goes to the surface of the
epithelium
 Near the end of the olfactory rod is a
knob from which olfactory cilia project

17. Perceptual Organization
 Gestalt psychologists: “The whole is more
than the sum of the parts.”
 The overriding principle of perceptual
organization is that of pragnanz: the
organizational processes will produce the
simplest possible organization allowed by
the conditions

18. Ruben’s vase

19. Gestalt organizational principles

20. Configural dimensions. The bracket context helps in discriminating
the line whose slope is different from the rest
Tilted-T group appears
more distinct from
upright T’s than do
backward-L characters

21. Human Factors &
Ergonomics
Selection & Control of Action

22. Speed–accuracy trade-
off. Depending on
instructions, payoffs, and
other factors, when a
person must choose a
response to a stimulus,
he or she can
vary the combination of
response speed and
accuracy between the
extremes of very fast
with low accuracy or
very slow with high
accuracy

23. Hick–Hyman law:
Reaction time increases
as a function of the
amount of information
transmitted

24. Central bottleneck model. Response selection for task 2 cannot
begin until that for task 1 is completed. S1 and S2 are the stimuli
for tasks 1 and 2, respectively, and R1 and R2 are the responses.

25. Fitts’s law: Movement
time increases as a
function of the index
of difficulty
[log2(2D/W)]

26. Human Factors &
Ergonomics
Informational Processing

27. Two representations of information processing: (a) traditional open-
loop representation from cognitive psychology; (b) closed-loop system,
following the tradition of engineering feedback models

28. Approaches to Informational
Processing
1. Stage approach: information was
conceived as passing through a finite
number of discrete stages
2. Ecological approach: emphasis on the
integrated flow of information through
the human, emphasizes the human’s
integrated interaction with the
environment
3. Cognitive engineering (cognitive
ergonomics): a hybrid of the two

29. Model of human information processing

30. Atention
 Human information processing as a
filtering process human attention
 Attention:
 Selective attention: chooses what to process in
the environment
 Focused attention: the efforts to sustain
processing of those elements while avoiding
distraction from others
 Divided attention: the ability to process more
than one attribute or element of the
environment at a given time

31. Selective Attention
 Influenced by:
 Salience
 Effort
 Expectancy
 Value

32. Focused Attention
 The goal is to maintain processing of the
desired source and avoid the distracting
influence of potentially competing sources

33.  Naraghi, 2003 (www.ctre.iastate.edu)

34. Sumber
 Naraghi, Hosein. 2003. Human factors in road traffic.
http. http://www.ctre.iastate.edu/educweb/ce552/docs/O
gden/D_Human%20factorschap3%20ogden.ppt.
 Proctor, R.W dan Proctor, J.D. 2012. Sensation and
Perception. Handbook of Human Factors and Ergonomics
4th ed., Gavriel Salvendy (Ed). New Jersey: John Wiley &
Sons, Inc.
 Proctor, R.W dan Vu, K.L. 2012. Selection and Control of
Action. Handbook of Human Factors and Ergonomics 4th
ed., Gavriel Salvendy (Ed). New Jersey: John Wiley & Sons,
Inc.
 Wickens, C.D dan Carswell, C.M. 2012. Informational
Processing. Handbook of Human Factors and Ergonomics
4th ed., Gavriel Salvendy (Ed). New Jersey: John Wiley &
Sons, Inc.