MIL-STD-46855 Human Engineering Requirements For Military Systems, Equipment, And FacilitiesThis standard establishes and defines the requirements for applying human engineering to the design, development, and acquisition of military systems, equipment, and facilities. These requirements include the work to be accomplished in conducting a human engineering effort integrated with the total system engineering and development effort. These requirements are the basis for including human engineering in proposals; system, equipment, software and associated user interfaces, and facility analysis, design and test; and documentation and reporting.

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MIL-STD-46855A

5.2.3 Models and mockups.

5.2.3.1 Generate computer models. As required, three-dimensional computer models, rapid prototyping, and computer-aided design/computer-aided manufacturing (CAD/CAM) techniques shall support the development of the design of systems, subsystems, equipment, components, or facilities for which human performance will be a determinant of operational performance and maintenance effectiveness. Additionally, when appropriate, the use of rapid prototyping of user interface designs, the use of task network and workload models to evaluate procedures, and other forms of modeling and simulation shall be considered. Computer models shall be able to provide relevant anthropometric information (such as a suitable range of body sizes, clothing, and

postures for evaluating proposed designs and design changes in terms of compatibility with whole-body fit and access; finger, hand, arm, foot, leg, and other access and reach; visual field; and strength). Computer models shall not be used for compliance testing of human performance and human engineering design. When used for predictive purposes, such models shall produce accurate and empirically repeatable, valid outputs. Computer models, simulations, rapid prototyping outputs, and CAD/CAM designs shall be available during technical meetings and design reviews.

5.2.3.2 Fabricate three-dimensional mockups. Prior to the fabrication of system prototypes, full-scale three-dimensional mockups of equipment involving critical human performance shall be constructed. The mockups shall be constructed sufficiently early to ensure that results of human engineering evaluations can influence design. The mockups shall be no more elaborate or expensive than is essential to represent those aspects of the human-system interface to be evaluated. These mockups shall provide a basis for resolving operational and maintenance access, workspace, and related human engineering problems, and for incorporating solutions into system design. In those design areas that involve critical human performance and for which human performance measurements are necessary, development of functional mockups shall be accomplished. The mockups shall be available for inspection as determined by the procuring activity. Disposition of mockups, after they have served the purposes of the contract, shall be as directed by the procuring activity.

5.2.3.3 Use scale models. Scale models may be used to supplement three-dimensional computer models, rapid prototyping, CAD/CAM, or mockup techniques, but shall not be substituted for mockups unless such substitution provides equivalent, valid, repeatable, and accurate information in a cost-effective and timely manner.

5.2.3.4 Use dynamic mockups. Dynamic mockups (full-scale physical models which simulate functions), shall be used when static, three-dimensional mockups are inadequate for assessing human performance in the design of complex systems. These mockups shall be used to:

a. Evaluate operator and maintainer procedures and user-system interfaces, and identify any potentially unsafe procedures or unacceptable workload demands;

b. Evaluate interaction between individual operators and/or maintainers;

c. Evaluate the non-mechanical aspects of a design, such as communications, information requirements, and display formats;