A High-Speed Analog-Digital Computer for Simulation

This paper describes the principles of operation and logical design of an analog-digital computer capable of simulating complex physical systems in real time. Information in the machine is represented by an analog voltage pulse and a digital number. Arithmetic operations are performed in time-shared analog computing components and conventional digital logical elements. A novel floating-point arithmetic feature is provided to extend the dynamic range of the machine variables. Instructions and constants are stored on a magnetic drum before computation begins. The instructions determine the sequence of computer operations, and both the instructions and constants are arranged so that random access to the drum is not needed. The programming techniques developed for the computer are described. The inherent simplicity of these techniques should permit engineers directly concerned with simulation to program their own problems for computer solution.