In
optimal control theory, a control is a variable chosen by the controller or
agent to manipulate
state variables, similar to an actual
control valve
A control valve is a valve used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller. This enables the direct control of flow rate and the consequential control of process quantities such as pres ...
. Unlike the state variable, it does not have a predetermined
equation of motion. The goal of optimal control theory is to find some
sequence
In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is cal ...
of controls (within an admissible set) to achieve an optimal path for the state variables (with respect to a
loss function).
A control given as a function of time only is referred to as an ''
open-loop control''. In contrast, a control that gives optimal solution during some remainder period as a function of the state variable at the beginning of the period is called a ''
closed-loop control
A closed-loop controller or feedback controller is a control loop which incorporates feedback, in contrast to an ''open-loop controller'' or ''non-feedback controller''.
A closed-loop controller uses feedback to control states or outputs of a dy ...
''.
See also
*
Control loop
A control loop is the fundamental building block of control systems in general and industrial control systems in particular. It consists of the process sensor, the controller function, and the final control element (FCE) which controls the proce ...
References
Control loop theory
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