We made a model for the dither angular stabilization system c1ass.mdl. The attached file shows the diagram.
The idea is to dither a combination of 6 optics (ETMs, ITMs, PZTs) at different frequencies and demodulate three PDs (TRX, TRY, REFL11I). Then form the DOFs from demodulted signals, filter, and send each DOF to a combination of optics.
This is enough to get started with arm cavities alignment (we may need to add the BS for the Y arm). More optics and PD can be added as they become available and/or needed.
The DAC for the fast PZT are not connected and have to be commissioned.