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).Algorithms
When you tune a control system, the software converts each tuning goal into a normalized
scalar value f(x). Here, x is the vector of free (tunable) parameters in the control system.
The software then adjusts the parameter values to minimize f(x) or to drive f(x) below 1 if
the tuning goal is a hard constraint.For Overshoot Goal, f(x) reflects the relative satisfaction or violation of the goal. The
percent deviation from f(x) = 1 roughly corresponds to the percent deviation from the
specified overshoot target. For example, f(x) = 1.2 means the actual overshoot exceeds
the target by roughly 20%, and f(x) = 0.8 means the actual overshoot is about 20% less
than the target.Overshoot Goal uses T∞ as a proxy for the overshoot, based on second-order model
characteristics. Here, T is the closed-loop transfer function that the requirement
constrains. The overshoot is tuned in the range from 5% (T∞ = 1) to 100% (T∞).
Overshoot Goal is ineffective at forcing the overshoot below 5%.This tuning goal also imposes an implicit stability constraint on the closed-loop transfer
function between the specified inputs to outputs, evaluated with loops opened at the
specified loop-opening locations. The dynamics affected by this implicit constraint are the
stabilized dynamics for this tuning goal. The Minimum decay rate and Maximum
natural frequency tuning options control the lower and upper bounds on these implicitly
constrained dynamics. If the optimization fails to meet the default bounds, or if the
default bounds conflict with other requirements, on the Tuning tab, use Tuning Options
to change the defaults.10 Control System Tuning