Gain-scheduled feedback document handling control system

A system for performing sheet registration, the system comprising:

• one or more sensors;
• a plurality of drive rolls;
• a plurality of motors, wherein each motor is associated with at least one drive roll;
• and
• a processor,
• wherein the processor comprises:
• a state determination module for identifying a state vector for a sheet, wherein the state vector comprises a plurality of state variables, wherein the state determination module identifies the plurality of state variables a plurality of times for the sheet,
• an observer module for determining error-space state feedback values based on a difference between each state variable and a corresponding reference state variable based on a desired sheet trajectory,
• a drive roll velocity determination module for determining desired velocity values for each drive roll based on the error-space state feedback values and one or more gain values, wherein the one or more gain values are based on pseudo-linearized error space state equations, and
• a motor controller for determining a motor control signal for each motor, wherein each motor control signal imparts a desired angular velocity value for at least one drive roll,
• wherein the processor is configured to perform the operations of the state determination module, the observer module, the drive roll velocity determination module, and the motor controller a plurality of times for a sheet, whereby the sheet is registered to the desired sheet trajectory.