Tridac, a large analogue computing machine

Tridac is the name given to a large analogue computing machine installed at the Royal Aircraft Establishment. The machine, which has been built to assist in solving guided-weapon problems, has electronic, mechanical and hydraulic components, and operates on a 1:1 time scale so that real components can be included in the computation. Tridac is intended to assist system understanding and development by constructing system models with which mathematical computations can be carried out. Each computing section, the parameters of which can be easily changed, represents a particular part of the real system. The mathematical operations of summation, integration, multiplication and resolution are carried out using either drift-corrected d.c. amplifiers or electrically controlled servo motors, with hydraulic or electric power. Connections to the servo motors and interconnections between the various cabinets, which contain in all some 2000 electronic units, are arranged to facilitate the simulation of the flight of a guided missile. Principles of operation, computing methods and components, installation, and method of operation of the computer are discussed with reference to the problems to be solved.