Research Guidelines for Digital Computer-Controlled Systems for Checkout and Fault Isolation

The past decade has seen a tremendous increase in the complexity and capability of aerospace and weapons systems. However maintenance philosophy and checkout procedures have not kept pace. The maintenance procedures have been evolving slowly through three major phases: a. Manual Maintenance Procedures b. Serially Programmed Automatic Test Equipment c. Computer-Controlled Automatic Test Equipment In the latter case a small but highly capable general-purpose digital computer is used as the controller for the Automatic Test Equipment. Once a general standardized programmed set of stimuli and measuring instruments is incorporated in a computer-controlled automatic test system, one need only modify the program in the Automatic Test Equipment system memory rather than develop a new set of test equipment for each new system under test. Much of the basic feasibility work has already been completed for such computer controlled Automatic Test Equipment. This is summarized along with discussion of remaining problem areas. Of especial importance is the dependence of program details on the level of tests to be performed; e.g. overall system checkout or isolation of fault to subsystem, assembly, chassis, module, or component. It is shown that while the program details differ, the same test philosophy can be applied.