Mechanical deflection estimation for ink-jet service station motion servo
AssigneeHewlett-Packard Development Company, L.P.
InventorsDouglas L. Harriman, Kris M. English, Daniel J. Magnusson
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Abstract
Resting position error recognition for an ink-jet, translational-type, service station mechanism. Service station drive mechanism binding due to hard stop impact is compensated for by calculating a difference between when the drive mechanism stops and when a predetermined velocity change was first recorded. In a more sophisticated embodiment, noise filtering is employed to improve accuracy with increasing number of uses of the service station mechanism.
Claims13
A method for correcting mechanical deflection errors in an ink-jet apparatus motor-driven translational-motion service station mechanism, the method comprising:
- recording velocity data and position data associated with the mechanism during a slew toward a hard stop;
- and
- following impact between the mechanism and the hard stop and cessation of motor drive, determining from said velocity data a first position data point indicative of first contact between the mechanism and the hard stop, and using a difference between said first position data point and a current position data point as a mechanism binding estimate.
A motion servo subsystem, having encoding means for providing signals indicative of velocity and position, comprising:
- means for storing a time-synchronized chronological set of velocity data and position data;
- means for searching said velocity data and for determining a last time of full velocity;
- means for indexing into said position data using said last time of full velocity and for obtaining a time-synchronized position therefrom;
- and
- means for calculating a value indicative of servo subsystem overshoot from said time-synchronized position and current position.
A hard copy apparatus, having a motor-driven translational ink-jet service station subsystem using a hard stop locator, comprising:
- program code for recording velocity data and position data associated with the mechanism during a slew toward the hard stop locator;
- program code for determining from said velocity data a first position data point indicative of first contact between the mechanism and the hard stop locator following impact between the mechanism and the hard stop and cessation of motor drive;
- and
- program code for using a difference between said first position data point and a current position data point as a mechanism binding estimate.
A memory device adapted for use in association with hard copy apparatus having a motor-driven translational ink-jet service station subsystem using a hard stop locator, comprising:
- program code for recording velocity data and position data associated with the mechanism during a slew toward the hard stop locator;
- program code for determining from said velocity data a first position data point indicative of first contact between the mechanism and the hard stop locator following impact between the mechanism and the hard stop and cessation of motor drive;
- and
- program code for using a difference between said first position data point and a current position data point as a mechanism binding estimate.
The device as set forth in claim 13 further comprising:
- program code for filtering position data used for said obtaining a time-synchronized position to remove data collection quantization noise therefrom.
Dependencies are inferred from the claim text.