In need of a model for complexity assessment of highly automated human machine systems Fredrik...
-
Upload
angelica-viner -
Category
Documents
-
view
213 -
download
1
Transcript of In need of a model for complexity assessment of highly automated human machine systems Fredrik...
In need of a model for complexity assessment of highly automated human machine systemsFredrik Barchéus, Pernilla Ulfvengren, Johan Rignér
Content
• Goal of research• Purpose of paper• Future ATM, context• Theory; Human Factors, automation and complexity• Models of complexity• Conclusion and discussion
Goal of our research
• Apply and integrate knowledge of human factors into development and continuous improvement of critical systems in order to improve overall system performance.
Purpose of this paper
• Initial work, problem definition and ideas for further research
• Link multiple areas of research- Design and system development- Human Factors and User Centered System Design- Automation and complex systems- Models of complexity
• Identify potential criteria for human factors specific to operating in highly automated and complex systems.
• Explore future research needed to develop a model for complexity assessment in these systems
Future ATM system – Multiple goals
• Commercial pressure• Demand for increased capacity• Descrease costs• Decrease environmental impact• Increase efficiency • Increase safety
• Deployment of new technologies• Shift of paradigm: airspace based to trajectory based• High level automation• Integrated systems
Effects and consequences of future system on human operators and system performance
• New operational rules, new tasks, new roles• Increased automation
- ”Ironies of automation”- Less operator understanding/predictability of operational
processes• Change of responsibilities among human roles:
- air traffic controllers, pilots, ground handlers etc.• Various levels of automation in new and old parts in
operating system.• Actors with different technologies in joint systems
Multiple goals, trade-offs in design
• Good design – managing trade-offs- To evaluate your design choices- There is no perfect solution- You need to know the trade-offs.
• The perfect car:
DC3 aircraft – made aviation available to public Not best on any single parameterBest trade-offs between speed, comfort, price, size etc.
Design and system development process
• Design requirements:- Precise, limited design requirements specification- Both enabler and blocker of designing for operability with
full functionality.• Timing: identifying needs for improvement
- Easier and cheaper to change early in design phase.- An alternative is to add restrictive user instructions
• In IT-systems design: - Insufficient or faulty initial requirements. - Customer may not define or even know what design
requirements that will fulfill operational requirements
Human Factors and User-Centered System Design
• Needs driven, context and operational focus• Front-end analysis with user in early focus• Operator analysis difficult, too unspecified design
requirements.• Still not always applied from the start of system
development. HF remains an add-on in design of human-machine systems.
Operational requirements
User requirements
Design requirements
Tech. requirements
”As few as possible”
User involvement and testing
Beyond normal operations, complexity
Automation and complexity• Automation
- Enable cost-effective systems- Enable safer systems- Affect work environment, content, tasks and procedures
• Imperfect automation leads to complacency and mistrust from operators
• Full automation in part hindered by insufficient data• The human remains in the system as a backup• ”Not all that could be automated should be
automated”• Levels Of Automation, LOA
Levels of automation
• 10 the computer does everything• .• .• .• .
• 5 the computer acquires information, suggest one solution and waits for the human to execute
• .• .• .
• 1 the human does everything
Levels of automation
Information acquisition
Information analysis
Decision selection
Action implementation
10....
5...
1
10....
5...
1
10....
5...
1
10....
5...
1
The Swiss cheese model of accident causation
Active errorsLatent conditions
Managerial decisions Training Operator error
Swiss cheese model
Tightly coupled automated systems
Decision to automate
Complexity of technological systems
Coupling
Interactions
Universities
Nuclear plant
Aircraft
ATM
Assembly-line production
Most manufacturing
Dams
Loose
Tight
Linear Complex
CDMAutomation
SWIMASAS
?
Quantifying interactions
• ASAS Free Flight
2
1
nnmV
V=6 V=3Controller separation Pilot separation
V=12Pilot separation(System)
Complexity assessment of changed responsibilities
Task migration
Emergent cognitive functions
Default case
Pilot Controller
Controller Pilot
Layered model for System of Systems
δγβα
Resources
δγβα
Operations
δγβα
Economics
δγβα
Policy
aircraft, crew, engineers…
Development, ATM, airline…
Regulations, SOP’s…
Individual
Team
Organisation
Example: Multitude of equipment and procedures
• Aircraft descent from a pilot’s perspective- Airspeed mode- Vertical speed mode- FMS mode• Manufacturer and airline economic profile differs
• Trajectory differs between different modes
Aircraft
Example: Change of communication routes
Pilot Cabin
Catering
Aircraft
Pilot Cabin
Catering
Before After
Example: Change of responsibility and procedures
• ASAS applications- ASAS Self separation- ASAS Separation- ASAS Spacing
Self separation
Separation
Spacing
Default
Controller
Pilot
Validity of models and methods
• Simplifications• Cover only sub-systems under certain conditions• Use of domain knowledge• Simulation models need valid basic assumptions• Purpose of automation model(s)?
- Training, procedure design- Limited wider modeling applicability
Future system - Again
• Multitude of equipment and procedures- More interactions – higher complexity
• Change of communication routes- Changed interactions – complexity?
• Change of responsibilites and procedures- Changed interactions – complexity?
• Highly automated- Tightly coupled – error propagation
• Significant system integration- More/less complexity?
Conclusion and discussion
• Complexity and automation highly intertwined in the context of SESAR and the future European ATM system- Paradigmatic change – viability of old methods and
models- Old systems remain in new context – new interactions
need new reassessments- Mixed system functionality and equipage – full system
assessment- Lack of “full context” – careful use of domain expert
knowledge
• Collaboration between ComplexWorld and HALA!
Thank you!
Questions?
KTH Royal Institute of TechnologyStockholm, Sweden