Analysis Techniques For Man-Machine Systems Design

NATO UNCLASSIFIEDAC/243(Panel 8)TR/7 - 78 -Volume 24.4 INFORMATION/ACTION OR ACTION/INFORMATION TABULATIONSWhat the technique doesMasSfunThese are comparatively simple techniques for conducting a task analysis which emphasizes the informarion requiredby the operator to perform his or her task. Both analyses are hierarchical: they are based on those functions whichhave been allocated to the operator(s). Each function is analysed in turn to identify the operator's tasks. The 5.4.information/action analysis starts by analysing the information related to each function in sequence and defining theoperator's tasks, and the actions associated with each item of information (see Drury et. al., 1987; Meister, 1985;Woodson, 1981). The actionfinformation analysis is conducted by analysing an operator's tasks and actions insequence, as a series of discrete steps, to identify the information required for each action.Inputs to the techniquesThe analyst/user requires information on the actions tobe taken by the operator, or, conversely, the informationwhich the operator will be given by a specific systemstate.Outputs of the techniquesThe techniques produce tabulations of the informationprovided to the operator, the action taken upon receipt ofthe information, and optionally, the feedback to theoperator.5.4When to useThe techniques are of use in concept development, and particularly, in preliminary design. They may be preceded byone of several types of function analysis: Function Flow Diagrams (2.1), Sequence And Timing (SAT) analysis(2.2), Information Flow and Processing Analysis (2.4). They may be incorporated into Requirements AllocationSheets (3.5). Information/Action, or Action/Information analyses produce information which can be used either formore detailed task analyses (4.5), for display concept development or analysis of Critical Design Requirements (6.2),for Error Analysis (5.7), or for Link Analysis (6.3).MiFL1lRelatedtechniquesThe techniques are two of several tabular task-analysis techniques all of which analyse the operator's tasks as a seriesof actions in response to information inputs.Resources requiredThe analyst requires the information identified under "inputs." No technical resources are necessary, but a computersystem is recommended to keep track of the many details that are created, and to facilitate modification.tNATO UNCLASSIFIED- 78 -