Apparatus and method for controlling product grade changes in a paper machine or other machine

An apparatus comprising:

• at least one processor operable to:
• identify a target for at least one controlled variable and a target for at least one manipulated variable, the at least one manipulated variable and the at least one controlled variable associated with production of a product;
• identify a trajectory for the at least one manipulated variable and a corresponding trajectory for the at least one controlled variable using the targets;
• and
• implement a grade change using the trajectories so as to transition from production of the product having a first grade to production of the product having a second grade;
• and
• at least one memory operable to store the targets and the trajectories.

A computer program embodied on a computer readable medium, the computer program comprising computer readable program code for:

• identifying a target for at least one controlled variable and a target for at least one manipulated variable, the at least one manipulated variable and the at least one controlled variable associated with production of a product;
• identifying a trajectory for the at least one manipulated variable and a corresponding trajectory for the at least one controlled variable, the trajectories identified using the targets;
• and
• implementing a grade change using the trajectories so as to transition from production of the product having a first grade to production of the product having a second grade.

A system, comprising:

• a paper machine operable to produce a paper sheet having multiple grades;
• and
• a controller operable to initiate a transition from a first grade to a second grade by:
• identifying a target for at least one controlled variable and a target for at least one manipulated variable;
• identifying a trajectory for the at least one manipulated variable and a corresponding trajectory for the at least one controlled variable using the targets;
• and
• implement a grade change using the trajectories so as to transition from production of the paper sheet having the first grade to production of the product having the second grade.