Method, apparatus, device and system for correction of encoder runout

Abstract

Methods, Apparatus, Devices and Systems herein load a firing distance into a distance counter of a printing device. The firing distance is the distance from the current position of a printhead of the printing device to a marking location on a substrate and the distance is calculated based on an angular encoder operatively associated with a roller used to transport a marking media to the printhead for marking. These devices and methods count the firing distance in angular distance increments as a function of the encoder angular position to correct for encoder roller runout using the distance counter, based on relative movement of the substrate and printhead. When the distance counter reaches the last discrete distance increment corrected for encoder roller runout of the firing distance, these devices and methods load the fractional remaining distance of the firing distance into a time counter of the printing device. Then, the fractional remaining distance is counted using velocity-based distance increments at regular time intervals using the time counter. When the time counter reaches the last velocity-based calculated distance increment of the fractional remaining distance, the marking material is transferred from the printhead to the substrate.