The cockpit relies heavily on the presentation of visual information. Adoption of auditory signals may reduce the workload experienced by pilots in the visual domain.
Localisation of auditory warnings
Similar sounding warnings emanating from similar areas may cause confusion
Adoption of white noise bursts within ambulance sirens
Visual modality is obviously extremely important in aviation. But can we always trust our eyes?
Visual modality is obviously extremely important in aviation. But can we always trust our eyes?
The visual scene is captured by the eye as a poor quality, two-dimensional representation
What is perceived is determined by:
‘Bottom-up’ processes. The percept of a stimulus is determined by features of the stimulus as processed by the visual cortex
‘Top-down’ processes. The interpretation (consciously or not) of a stimulus can be determined by our experience and knowledge
Important distinction!
Featureless surfaces, or those with textures of unknown sizes, can produce inaccurate judgements of size.
Featureless surfaces, or those with textures of unknown sizes, can produce inaccurate judgements of size.
Sea.
Beehives for caravans.
Can produce an inaccurate mental model of the situation which overrides the correct perception of the instruments.
Top-down influences.
Exacerbated by fatigue and workload.
Pilots may have to visually judge the glide slope without any cues other than those from the surface of the world.
Pilots may have to visually judge the glide slope without any cues other than those from the surface of the world.
The ‘aspect’ (retinal shape) of the runway is not very useful.
However, the visual touchdown point is a constant and unchanging cue, relative to the horizon.
If the horizon cannot be seen, its location must be implied,
The runway’s sides meet at the horizon.
The terrain’s texture gradients.
The relative position of the aircraft’s canopy.
Identification of a colliding aircraft is confounded by;
Identification of a colliding aircraft is confounded by;
Constant relative bearing.
Unique characteristic.
Periphery of retina detects sensitive to movement.
Non-linear increase in retinal size.
Retinal image doubles with each halving of closure distance.
Uneven visual acuity across the retina.
Maximal acuity at the fovea.
Detection only if pilot is looking directly at it.
Implications for visual scanning to acquire proximal image on the fovea.
Bottom-up (information from our senses) and top-down (expectations and experiences) processes affect the way we perceive the world.
Bottom-up (information from our senses) and top-down (expectations and experiences) processes affect the way we perceive the world.
The resultant perception is often not a true reflection of the external world.
This can be advantageous when it is in our interest for differences between features in the external world to be exaggerated but potentially catastrophic when perceptual illusions lead us to take inappropriate behaviour.
The HSI Framework – seven domains
The HSI Framework – seven domains
Manpower
Personnel
Training
Human Factors Engineering (aka Ergonomics)
Workplace design
Anthropometry
Critical Dimensions
System Safety
Health Hazards
Social & Organisational
HSI often called Human Factors Integration (HFI) – HFI is really the process by which HSI is applied to equipment procurement
Human Factors Engineering
Human Factors Engineering
(aka Ergonomics)
focused on the integration of human characteristics into system definition, design, development, and evaluation to optimise human machine performance under operational conditions.
Cockpits
Cockpits
Workstations
Control rooms
Offices
Transport systems
Factories
Inputs required from
Inputs required from
EHFA
Task analysis
Link analysis
Allocation of function
Consider
Operational and environmental context
Human dimensions
Biomechanics and physiology
Task issues
Task issues
Procedures
Critical elements
Responsibilities of organisation and individuals
Communications
Verbal
Non-verbal
Visual issues, such as sight lines
Flows of materials and personnel
Access and clearance
Normal
Emergency
Maintenance
Protection
Protective clothing & equipment
Barriers & guards
Physical human dimensions
Physical human dimensions
Population specific
Linear dimensions, for example:
Stature
Functional reach
Sitting height
Girth dimensions, for example:
Waist
Head circumference
Each dimension is expressed in terms of percentile
Requirements often state …must accommodate the 5th percentile and the 95th percentile human…
Requirements often state …must accommodate the 5th percentile and the 95th percentile human…
Choose dimensions relevant to the workstation, posture, and task
Sitting, standing, reach, fit, walking, crouching
5th percentile (smaller) dimensions considered for:
Seat adjustment, reach, vision, control movement, foot rests
95th percentile (larger) dimensions considered for:
Seat adjustment, ingress, fit, access, clearance
Clothing increases most dimensions through the addition of bulk
Clothing increases most dimensions through the addition of bulk
e.g. stature, sitting height, chest depth, shoulder breadth
But
Decreases the reach dimensions due to restriction of movement
e.g. functional reach, vertical functional reach
CADMID cycle
CADMID cycle
System Readiness Levels
(DEF STAN 00-250. May 2008; http://www.aof.mod.uk ; www.hfidtc.com )
MoD JSP to be introduced later this year
HSI covers all aspects of applied human factors
HSI covers all aspects of applied human factors
Human Factors Engineering is just one element that needs to be integrated
HSI comprises tools and processes that fit with systems engineering
HSI is widely applicable
Early inclusion is so much better than late intervention
Definitions
Models
Theory
Metrics
Applications
Limitations
“ . . . Knowledge of current and near-term disposition of both friendly and enemy forces within a volume of airspace.” McMillan (1994)
“ . . . Knowledge of current and near-term disposition of both friendly and enemy forces within a volume of airspace.” McMillan (1994)
“. . . One’s ability to remain aware of everything that is happening at the same time and to integrate that sense of awareness into what one is doing at that moment.” Haines & Flateau (1992)
“. . . A pilot’s continuous perception of self and aircraft in relation to the dynamic environment of flight, threats, and mission, and the ability to forecast, then execute tasks based on that perception.” Hamilton (1987)
Situation Awareness is . . .
Situation Awareness is . . .
When all is said and done we know that Situation Awareness refers to an operator’s knowledge and Understanding of the dynamic environment in which he/she is operating
When all is said and done we know that Situation Awareness refers to an operator’s knowledge and Understanding of the dynamic environment in which he/she is operating
It is knowledge of the ‘Big Picture’
SA provides the basis for subsequent decision making and performance in the operation of complex, dynamic systems
A series of complex cognitive processes, including: Perception, Working Memory, Pattern Matching, Attention and Long Term Memory
A series of complex cognitive processes, including: Perception, Working Memory, Pattern Matching, Attention and Long Term Memory
NOT ‘task’ or ‘individual’ specific
Also referred to as Situation Assessment (SAS)
Will be influenced by a multitude of ‘SA Factors’
These factors WILL BE ‘task’ AND ‘individual’ specific
These factors WILL BE ‘task’ AND ‘individual’ specific
Each factor will have different weightings or importance attached to it for differing military domains
The number of such factors is vast
The output of the SA PROCESS will be a number of ‘Situation Models’ (or dynamic mental models)
The output of the SA PROCESS will be a number of ‘Situation Models’ (or dynamic mental models)
These situation models are essentially knowledge and understanding
The quality of a person’s SA is defined by the match between these situation models and reality
The person will have a situation model for each of the relevant ‘SA Information Domains’ associated with a specific task or job
The person will have a situation model for each of the relevant ‘SA Information Domains’ associated with a specific task or job
Each SA information domain will comprise a number of ‘SA Elements’
Example: Endsley (2001) illustrates this for the task/job of piloting a civil aviation aircraft
The development and maintenance of SA occurs within an individual’s head
The development and maintenance of SA occurs within an individual’s head
The SA process (or SAS) is a generic continuous process/cycle that is impacted upon by many factors
These factors will vary in their importance and influence depending upon the specific task and the individual undertaking that task
SA can be applied to teams as well as to individuals
SA can be applied to teams as well as to individuals
Caution needed here, as SA cannot be shared (it resides inside the individual’s head), but information can be shared
We could be talking about:
1) The overlap in SA for the team
2) The SA of the team as moderated by the primary decision maker
3) The collective SA of the entire team
Crew SA
Crew SA
SA Global Assessment technique (SAGAT)
Snapshots
SA Flight Training Evaluator (SAFTE)
China Lake SA Scale (CLSA)
SA Rating Technique (SART)
SA Supervisory Rating Form (SASRF)
Physiological Measures: Eye Activity
Most SA measures have been designed using a particular SA definition, and with a specific application in mind
Most SA measures have been designed using a particular SA definition, and with a specific application in mind
Keep this in mind when selecting an SA measure
In practice, 2 of the SA measures outlined previously are used far more than the others:
SART (subjective)
SAGAT (objective)
This is probably due to the extensive validity data that accompanies these measures (we ‘know’ they are measuring SA)
There are three main military applications for SA research:
There are three main military applications for SA research:
1) System/interface design, development, assessment and evaluation
