Inertial Navigation System Simulator Program: Top-Level Design (1987)

A real-time Ada application, an Inertial Navigation System (INS) simulator, is being developed by the Real-Time Embedded Systems Testbed Project as a vehicle to analyze issues regarding the use of Ada in the real-time embedded domain and to provide a context for future experimentation. The technical philosophy behind developing a real-time Ada artifact is to: (1) select a representative (e.g., strict timing demands, multiple concurrent activities, low-level I/O, error handling, interrupts, and periodic activities) real-time application; (2) use Ada tasks as the unit of concurrency for the real-time design; and (3) apply any relevant practical results being produced by the real-time scheduling research community. In particular, the INS simulator must satisfy a set of timing requirements that are similar to an INS with respect to data updating, message transmission, and message reception. This document discusses the top-level design of this application from three points of view: data flow perspective, concurrency and control perspective, and the Ada module perspective.