SUSPENSION CONTROL: a joint Virgo/LSC workshop Giovanni Losurdo – INFN Firenze

ADVANCED LIGO 12 dof active control MIMO/SISO sensor blending “cradle effect” pre-isolation tilt subtraction … hierarchical control couplings local damping electrostatic actuators steep roll-off … Coll. meeting – Cascina, Feb 7th, 2007 G.Losurdo – INFN Firenze/Urbino 2/11

A WORKSHOP ON SEI/SUS CONTROL Suspension control issues have been crucial for Virgo so far They will be crucial for ADV LIGO as well The field usually receives little attention by the community Virgo/LIGO/GEO: different systems but many common problems Let us try to gather the experts and start to exchange knowledge (and hopefully people) 1-day workshop within one the next LSC-Virgo meetings (October meeting @ Hannover?) Coll. meeting – Cascina, Feb 7th, 2007 G.Losurdo – INFN Firenze/Urbino 3/11

LIST OF POSSIBLE TOPICS Control strategy Sensing noise and Error-Signal build-up (signal blending, sensor correction) Ground tilt on controlled suspension systems (pure mechanics, tiltmeters) Multi-Suspension system as whole (global control strategy for the suspension) Smart filters (environmentally adaptive strategies, digital adaptability) Coping with mechanical couplings (cross-talks specs and patches) Hierarchical controls/locking force reallocation strategy Feedforward Hardware improvement Electronics and actuators noise Fused silica fibers susp: problems and solutions Suspension point interferometer Coll. meeting – Cascina, Feb 7th, 2007 G.Losurdo – INFN Firenze/Urbino 4/11