Patent Document ID: 8360422
Application ID: 13051624
Patent Flag: 1

Claim One:
1. A method of aligning a sheet in a printing device, comprising: receiving a sheet by a device having a plurality of drive rolls, wherein each drive roll has an acceleration; identifying a desired trajectory for the sheet; selecting a reference frame having a reference state vector, wherein the reference state vector comprises coordinates of a point on the sheet, an angle of the sheet, and angular velocities and angular accelerations of at least two of the plurality of drive rolls; determining a current position of the sheet, wherein the determining a current position comprises: determining a state vector for a cart, the cart comprising a virtual body having dimensions relating to at least two of the plurality of drive rolls, and determining a desired cart trajectory based on the state vector and the reference frame; adjusting the acceleration of at least one drive roll based on the current position, the desired trajectory, the state vector and the desired cart trajectory; and repeating the determining and adjusting a plurality of times so that the sheet moves along the desired trajectory for the sheet.