Automatic alignment of a Michelson interferometer

A description is presented of the control system for the automatic control of a very large dual-wave Michelson interferometer to be used in the VIRGO experiment, a gravitational wave search in the 10-3000-Hz band. The system is mainly based on a VME bus architecture, for the local controls, on which numeric control systems based on digital filters are implemented. The control systems are described along with the way they are linked together to form the global control system, in a hierarchical configuration.<
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