A system of modular electrohydraulic servovalves is centrally controlled may be used to control the operation of critical hydraulic actuators. A programmable controller operates a group of modular servovalves which each deliver a portion of the total actuator fluid requirements. The flow rate, valve...http://www.google.co.uk/patents/US5322003?utm_source=gb-gplus-sharePatent US5322003 - Modular hydraulic control system
