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Dual Velocity Profiles for Voltage-Controlled Dc Motor

IP.com Disclosure Number: IPCOM000099911D
Original Publication Date: 1990-Feb-01
Included in the Prior Art Database: 2005-Mar-15
Document File: 2 page(s) / 48K

Publishing Venue

IBM

Related People

Cavill, BR: AUTHOR [+4]

Abstract

A software algorithm is defined which provides dual velocity profiles for a voltage-controlled DC motor. The present embodiment, the print head drive motor of a serial dot matrix printer, provides different print head velocity profiles for motions with printing and motions without printing. This scheme minimizes dot misregistration and printer shake when printing, and minimizes head travel time when not printing, thus maximizing acceptable quality printer throughput.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 84% of the total text.

Dual Velocity Profiles for Voltage-Controlled Dc Motor

       A software algorithm is defined which provides dual
velocity profiles for a voltage-controlled DC motor.  The present
embodiment, the print head drive motor of a serial dot matrix
printer, provides different print head velocity profiles for motions
with printing and motions without printing.  This scheme minimizes
dot misregistration and printer shake when printing, and minimizes
head travel time when not printing, thus maximizing acceptable
quality printer throughput.

      For head motions without printing, a trapezoidal profile is
implemented which provides efficient head speeds without concern for
print-wire-imposed limitations.

      For head motions with printing, a smoothed profile is
implemented.  The effective head acceleration and deceleration with
this profile is less than that of a trapezoidal profile using the
same maximum acceleration/deceleration.  Since the profile is
rounded, the overshoot above nominal print speed can be held to a
minimum.

      The figure shows the dual profiles of the present embodiment.
The algorithm to implement these profiles is defined below.
   1.  A table of desired velocities is defined for each profile.  In
the case of the trapezoidal profile, the table may be reduced to a
single entry.
   2.  During each head motion command decode, a flag is set
indicating the type of move required. In one state, the flag
indicates motion without print. ...