Basics of Mission : Function: Task Analyses

1. Basics of Mission: Function: TaskAnalyses The Importance of System/Organizational Alignment

2. Mission Task Analysis: 3 Levels • Mission -- identify system/organizational goal requirements that map to human performance requirements • Function -- allocate functions and identify machine-related requirements that translate into human performance requirements • Task -- identify specific behaviors, estimate workload, evaluate potential errors.

3. Mission Task Analysis • Mission Analysis • Mission Element Matrix • Design Reference Scenarios and time critical segments • Function Analysis • Functional breakout • Operator role definitions and function allocation • Provisional division of responsibility among crew members • Task Analysis • Human performance requirements • Information requirements • Characteristic errors

4. Mission Task Analysis in Design

5. Function Analysis Beginning with background in Operator Role Theory

6. Mission Task Analysis in Design

7. Operator Role Theory • Background • Originally developed to characterize human operator roles in air defense systems • Later expanded to include all types of systems • Basic assumptions • Performance of any function can be characterized by how humans vs machines perform the information processing in the decision making loop of that function • Characterized along a continuum ranging from entirely human to entirely machine

8. Continuum of Operator Roles

9. Decision Making Loop • Sensors extract data from the task environment • Processors transform and manipulate the data • Decision maker selects a response • Effectors act on the task environment, or on the sensors and processors

10. Depiction of Decision Making Loop Task Environment Sensor Effectors Processor Decision Maker Human-Machine System

11. Four Generic Operator Roles • Direct Performer -- human performs all info processing • Manual Controller -- decision making reserved for human • Supervisory Controller – machine (often software) can make decisions, but human can override machine • Executive Controller – machine performs all processing, human only starts/stops execution

12. Application of Operator Role Theory • Used to characterize (describe) relationship between humans and machines in the functions of human-machine systems • Provides a framework to guide function allocation decisions • Selection of levels of automation • Division of responsibilities between crewmembers • Supports development of specifications for software requirements

13. Function Analysis • Develop functional breakout • Analyze performance requirements for each function • Allocate functions

14. Functional Breakout • A function is a capability provided by the activity of system components • The functional breakout is the list of all functions required to operate system and perform assigned missions • Usually arranged hierarchically • Can be as many levels as are useful, but usually 2-4 levels are sufficient

15. Task Analysis

16. Mission Task Analysis in Design

17. Task Analysis • A task is a goal-directed activity or series of actions performed by a human operator • Task analysis involves • Identifying and describing operator tasks • Identifying performance requirements, information requirements and KSA requirements • Describing typical sequences of tasks • Identifying potential errors • Assessing operator workload (time and task demands)

18. Task Identification • Task taxonomy – the framework for describing and classifying tasks • Functional breakout usually provides a useful task taxonomy • Other standard taxonomies are also available • Tasks are identified from three primary sources • Mission requirements • Operator role in function • Equipment design details (e.g., setup tasks)

19. Task Requirements • Performance requirements • Can be explicit requirements for response time, accuracy, or magnitude • Generally the performance requirement is to perform as well as possible given operational constraints • Information requirements • Input requirements – information that needs to be provided to the operator so that the task can be performed • Output requirements – information that needs to be received from the operator so that the task can be performed

20. KSA Requirements • Knowledge – possession and command of an organized body of information necessary to perform the task • Skills – capability to perform required constituent activities to standards of time, accuracy, magnitude, etc. • Abilities – enduring physical or cognitive attributes required to become capable of performing the task (More on this in the Job Analysis section)

21. Operational Sequences • Typical operational sequences may be identified in the mission analysis or from equipment design details • Design should accommodate information requirements within operational sequences with minimal requirements for changing pages on multifunction displays

22. MTA Feeds to Other HSI Analyses Job Analysis Task List KSAs Mission Task Analysis Manning and Workload Analysis Scenarios Required tasks Error Analysis Potential Errors