Tuning

opt_rf_readout_phase OptimiseRFReadoutPhaseDC

This optimises the demodulation phase of ReadoutRF elements relative to some DegreeOfFreedom or driven Parameter in the model. The phases are optimised by calculating the DC response of the readouts. This Action changes the state of the model by varying the readout demodulation phases. If no arguments are given it will try to automatically optimise any lock element in the model that is using an RF readout with respect to the lock feedback parameter.

Syntax:

opt_rf_readout_phase(*args, d_dof=1e-10, name='optimise_demod_phases_dc')

Required:

args: Pairs of DegreeOfFreedom or Parameter and ReadoutRF elements, or pairs of their names. If none are provided OptimiseRFReadoutPhaseDC will automatically search for Lock elements which have ReadoutRF error signal and optimise them.

Optional:

d_dof: A small offset applied to the DOFs to compute the gradients of the error signals

sensing_matrix_dc SensingMatrixDC

Computes the sensing matrix elements for various degrees of freedom and readouts that should be present in the model. The solution object for this action then contains all the information on the sensing matrix. This can be plotted in polar coordinates, displayed in a table, or directly accessed.

The sensing gain is computed by calculating the gradient of each readout signal, which means it is a DC measurement. This will not include any suspension or radiation pressure effects. This action does not modify the states model.

Syntax:

sensing_matrix_dc(dofs, readouts, d_dof=1e-09, name='sensing_matrix_dc')

Required:

dofs: String names of degrees of freedom

readouts: String names of readouts

Optional:

d_dof: Small step used to compute derivative

set_lock_gains SetLockGains

An action that computes the optimal lock gains using the sensing matrix found with SensingMatrixDC. This action computes the error signal gradient for each lock with respect to its drive and sets the gain as -gain_scale/sensing.

Syntax:

set_lock_gains(
    *locks,
    d_dof_gain=1e-10,
    gain_scale=1,
    name='set gains',
    optimize_phase=none,
    verbose=false
)

Required:

name: Name of the action.

verbose: If True this will print the name of the enabled locks and their gains.

Optional:

\*locks: A list of locks for which to set the gain. If none provided, all enabled locks in model are used. Disabled locks that are explicitly listed will have their gains set.

d_dof_gain: Step size to use when calculating the gain for each error signal/DOF pair.

gain_scale: Extra gain scaling factor applied to the gain calculation: -gain_scale/sensing In multiple lock models where the locks are cross coupled using a gain_scale < 1 can improve the stability of the locking algorithm to stop excessively large steps.

optimize_phase: Deprecated feature: Use OptimiseRFReadoutPhaseDC instead

See Also:: opt_rf_readout_phase, sensing_matrix_dc

get_error_signals GetErrorSignals

An action that quickly calculates the current error signals for all or a subset of locks in a model.

Syntax:

get_error_signals(*locks, name='get error signals')

Required:

name: Name of the action.

Optional:

\*locks: A list of lock names to compute the error signals for. If not provided, all locks in model are used.