Analysis Procedures Goal Statement - Purpose of the Analysis Examples: Process Improvement, Product Improvement, Increase Safety, Decrease Personnel Requirements, etc Mission Analysis Assumptions and Constraints Mission Segments/Phases Evaluation Criteria Function Determination / Allocation Function Reallocation Task Description / Analysis SubTask Description Sub-SubTask Description

Importance of Function & Task Analyses Evaluate Human Factors Implications Design Requirements and Constraints Workload Implications Notes: 1. Decompose to level where functions to be performed by system can be identified. 2. Be careful that proposed design solution does not appear to be a function description. Meister pp 9-10, Tables 2.1 & 2.2

Mission Analysis (System Requirements Analysis) What is the system supposed to accomplish? The analyst/designer needs to know - Specific Goals Required Outputs Required Inputs System Capacities and Performance Requirements Operating Environmental Factors Constraints on System Operation

Mission Analysis Tools Mission Profile Graphic Description (Example - Flight Profile) Mission Scenario Verbal Description - Summarizes typical assumptions, environments, operations. Mission Segment Time period of coherent activities with definite beginning and ending points. Indicates interaction among system elements. Aids in segmenting mission. Purpose: Helps develop smaller, more manageable units for analysis.

Determination of Functions Identify and Describe Functions - by Determining Function Inputs and Outputs Establishing Functional Performance Criteria Preparing Functional Flow Diagrams Function Examples: To Detect To Repair To Analyze Functions - Can be Instantaneous (Start Engine) Prolonged ( Monitor Radar Screen) Complex (Analyze Equipment Malfunction) Note: Function translates inputs into outputs. Functions are hierarchical (that is, are layered). Difficult to differentiate between functions and tasks --- functions fade into tasks.

Function Performance Criteria Yardstick used to measure/predict whether or not the system/function meets the performance requirements. Criteria can range from gross to finely detailed. Functional Performance Criteria must be stated in terms of those test results that must be satisfied in order for the system/function to meet the performance requirements. Provides the basis for preparing the Functional Flow Diagram.

Functional Flow Diagram Determine the functions that have already been allocated. Describe the various different ways that each unallocated function might be accomplished. Establish the weighting criteria for comparing the alternatives. Compare each of the alternative against one another. Select the most cost-effective design. Meister pp 26-28, Tables 2.4, 2.5, 2.6

Task Description / Identification Examine each selected design alternative. List in sequence all the actions that must be performed to accomplish the functional element. Categorize actions in terms of whether they are operator or maintainer activities; and by the hardware/software subsystems to which they belong. Describe each action in terms of a behavioral verb (see next slide). Break tasks down into subordinate tasks by specifying inputs and outputs for each task/subtask. Meister p 36, Table 2.7

Behavioral Verbs Example - to turn on, to monitor, to disassemble Action Example - to turn on, to monitor, to disassemble Equipment Acted Upon Example - switch, motor, display Consequence of Action Example - voltage display stabilized Stimulus that Initiates the Action Example - pilot’s command Feedback Information Resulting form Task Performance Example - aircraft heading 320 degrees Criterion of task accomplishment Example - vehicle stopped/parked with 3 feet of marker

Task Analysis Design Questions Manning Questions Training Questions Test and Evaluation Questions Meister pp 31-32 See Lector Notes page 1 of 7

Design Questions What tasks need to be performed? How critical is each task? In what sequence must the tasks be performed? What control activations are required? etc, etc, etc Meister pp 33-35 See Lector Notes page 4 & 5 of 7

Manning Questions How many people are required to perform the task? What skill levels are required? Meister pp 35-37 See Lector Notes page 6 of 7

Training Questions On what behavioral dimensions are the tasks performed? How difficult or complex is each task? What information is required to perform the task? etc, etc, etc Meister pp 37-38 See Lector Notes page 7 of 7

Test and Evaluation Questions What are the performance criteria for the task or job? Meister p 38 See Lector Notes page 7 of 7