The OAO Simulation System

A simulation of the Orbiting Astronomical Observatory (OAO) is described. The simulator was a hybrid comprised of a prototype spacecraft and a digital computer and was capable of simulating virtually all the functions of an orbiting OAO spacecraft as well as a large number of possible malfunctions. Optical stimuli and a solar array simulator on the prototype spacecraft were elements of the simulation and were controlled by the computer. The simulation was used in verifying the design and performance of the OAO ground-system hardware and software and to train spacecraft controllers.