1 INTRODUCTION TO HUMAN FACTORS Dr Nathan Perry [email protected]101183 Behavioural Science What is Human Factors? Understand human interactions with a system Factors that influence human performance What is Human Factors? Human Characteristics Task Characteristics Environment Attention capacity Workload Illumination Working memory capacity Level of training Noise Expertise Display design Vibration Communication skills Organisational Culture Climate Personality Technological reliability Altitude
Working Memory: Short-term memory store which enables the manipulation of information
Long-Term Memory: prolonged storage of information for later retrieval
Cognitive Factors
Memory: Human Factors Implications
Working Memory: Processing requirements exceed working memory capacity performance decline
Long-term memory: Inability to retrieve information
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Cognitive Factors
Working Memory
Rail Control Example
Cognitive FactorsDecision-MakingDefinition: Choice between alternative options or courses of action
Theorised to involve:(a) Information acquisition(b) Information interpretation(c) Planning and selecting choices
Cognitive Factors
Decision-Making
Use a range of different decision strategies
Simple Complex
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Cognitive Factors
Decision-Making
Situation Simple or Complex
Requires Accuracy Complex
Little Time Available Simple
Vast amount of information
Simple
Little Task Experience Complex
Cognitive FactorsDecision-Making: Expertise Interviews with expert Fire Ground Commanders
Don’t compare and contrast decision options Recognise the situation
Use cues present in the environment to recall similar situations from memory
Use strategy taken in previous situation
Klein (1989)
Cognitive Factors
Decision-Making: Human Factors Implications
Tendency to limit info. analysis Effortful & time-consuming
Reduced potential for accuracy
Implement systems to reduce effort associated with info. analysis
Perry et al. (2012)
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Cognitive Factors
Decision-Making: Human Factors Implications
Display critical information
Advises on a course of action
Determines and executes course of action
Traffic Collision Avoidance System (TCAS)
Climb! Climb! Descend! Descend!
Cognitive Factors
Attention Information processes require attention
Limited attention capacity Cannot attend to everything
Without attention information unlikely to be processed
Cognitive Factors
Attention: Human Factors ImplicationsAttention required for info processing
Ensure that operators attend to crucial information
Design systems to ensure attention is given to crucial information
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Design
Lever underneath seat in van
Q: What will happen if
the lever is pulled?
A: Seat detaches from floor
Design
A: Mop sink
Design
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Design
System Design Airbus A320 accident in Strasbourg 1992
Pilot engaged behaviour that was inappropriate for current mode
Appropriate for different mode
Preparing to land – autopilot Needed change flight angle to 3.3 degrees
Flight management system set in the vertical speed mode Pilot dialled 3.3 into flight control unit In this mode this meant a speed of 3300 feet per minute! Instead of 800 feet per minute
Overreliance on Automation
Role of human operator with automated system is often to monitor
Humans have a tendency to put a lot of trust in automated systems
Out-of-the-loop performance problem Automation Induced Complacency Automation Bias Skill Loss
