State of the art high speed color printers require sheets being accurately positioned as they arrive to the image transfer station (ITS). This goal has been achieved by constructing and building a steerable nips mechanism, which is located upstream from the ITS. This mechanism consists of two rollers which not only rotate to advance the paper along the track, but also steer the paper in the yaw direction. This paper presents the design, experimental setup, system model, and the control law necessary to precisely correct for the lateral and angular positions of the sheet as well as to deliver it on time to the ITS. The system model is nonlinear and subject to four nonholonomic constraints. The control strategy used is based on linearization by state feedback with the addition of internal loops for the control of the process direction velocity and steering position of the rollers. This paper also provides a formal convergence analysis for the controller designed as well as the methodology required to tune it. The success of this mechatronic approach is corroborated through simulation and experimental results, which show that the controller is able to correct sheet errors under the condition that the page has nonzero initial and final longitudinal velocities.

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