Stephen John Fedigan

Gain-scheduled control for unmodeled subsystem dynamics

Abstract A method is developed, based on an extended D - K iteration procedure, for synthesizing controllers that are gain-scheduled on a priori unmodeled dynamics. A controller is designed for an example problem, and its performance is a significant improvement over a controller which is robust to the same set of unmodeled dynamics. In addition, a weighting filter synthesis method is presented which enables time-invariant parametric gain-scheduling problems to be translated into dynamic gain-scheduling problems, which reduces design complexity at the cost of controller performance.

Development of an Inkjet Carriage Motion Controller for Dynamic Print Mode Control

Abstract Typical inkjet printers print with a variety of user-selectable print modes, where media, cartridge and image processing attributes are statically defined for each print mode. In this paper, we present the development of an inkjet carriage motion control system in which the carriage motion attributes can be dynamically changed depending on the image content. The resulting system enables the development of Dynamic Print Mode Control (DPMC). DPMC achieves optimal trade-off between print quality and print speed by selecting an appropriate printing attributes based on arbitrary segmentations of different image contents. The two-degree-of-freedom (TDOF) controller combines a disturbance observer with a filtered zero-phase error tracking controller (ZPETC) for high tracking performance under uncertain disturbances and model uncertainties. Experimental results show an excellent performance under fixed-point controller implementation.