A microprocessor based variable structure control system for synchronous high speed film cameras

A microprocessor-based fully digital DC phase lock servo system has been designed for the JX-300 series synchronous high-speed film cameras. A discrete variable structure integral controller was proposed and used in the system, both in speed loop and phase-locking loop. The controller is practically a quasi-sliding mode discrete variable structure controller cascaded with an integral controller, so it possesses the optimum blend of properties of these two controller types.