Specify the tolerance in the location of the crossover frequency, in decades. For
example, to allow gain crossovers within half a decade on either side of the target
crossover frequency, enter 0.5. Increase the crossover tolerance to increase the ability
of the tuning algorithm to enforce the target loop shape for all loops in a MIMO
control system.- Enforce goal in frequency range
Limit the enforcement of the tuning goal to a particular frequency band. Specify the
frequency band as a row vector of the form [min,max], expressed in frequency units
of your model. For example, to create a tuning goal that applies only between 1 and
100 rad/s, enter [1,100]. By default, the tuning goal applies at all frequencies for
continuous time, and up to the Nyquist frequency for discrete time.- Stabilize closed loop system
By default, the tuning goal imposes a stability requirement on the closed-loop transfer
function from the specified inputs to outputs, in addition to the gain constraint. If
stability is not required or cannot be achieved, select No to remove the stability
requirement. For example, if the gain constraint applies to an unstable open-loop
transfer function, select No.- Equalize loop interactions
For multi-loop or MIMO loop gain constraints, the feedback channels are automatically
rescaled to equalize the off-diagonal (loop interaction) terms in the open-loop transfer
function. Select Off to disable such scaling and shape the unscaled open-loop
response.- Apply goal to
Use this option when tuning multiple models at once, such as an array of models
obtained by linearizing a Simulink model at different operating points or block-
parameter values. By default, active tuning goals are enforced for all models. To
enforce a tuning requirement for a subset of models in an array, select Only Models.
Then, enter the array indices of the models for which the goal is enforced. For
example, suppose you want to apply the tuning goal to the second, third, and fourth
models in a model array. To restrict enforcement of the requirement, enter 2:4 in the
Only Models text box.For more information about tuning for multiple models, see “Robust Tuning
Approaches” (Robust Control Toolbox).10 Control System Tuning