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Signal Types


The plant inputs are the independent variables affecting the plant. As shown in MPC Modeling, there are three types:

Measured disturbances

The controller can't adjust them, but uses them for feedforward compensation.

Manipulated variables

The controller adjusts these in order to achieve its goals.

Unmeasured disturbances

These are independent inputs of which the controller has no direct knowledge, and for which it must compensate.


The plant outputs are the dependent variables (outcomes) you wish to control or monitor. As shown in MPC Modeling, there are two types:

Measured outputs

The controller uses these to estimate unmeasured quantities and as feedback on the success of its adjustments.

Unmeasured outputs

The controller estimates these based on available measurements and the plant model. The controller can also hold unmeasured outputs at setpoints or within constraint boundaries.

You must specify the input and output types when designing the controller. See Input and Output Types for more details.

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