Browse Prior Art Database

Algorithm for Automatic Loading of Disks onto a Warped Pallet

IP.com Disclosure Number: IPCOM000110283D
Original Publication Date: 1992-Nov-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 3 page(s) / 110K

Publishing Venue

IBM

Related People

Mueller, WH: AUTHOR [+2]

Abstract

Described is an algorithm for computing the correct directional loading factors during the loading and unloading of disks onto a holding pallet. The algorithm functions in conjunction with a robot and laser measurements so as to compensate for variances and warpages of holding pallets.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Algorithm for Automatic Loading of Disks onto a Warped Pallet

       Described is an algorithm for computing the correct
directional loading factors during the loading and unloading of disks
onto a holding pallet.  The algorithm functions in conjunction with a
robot and laser measurements so as to compensate for variances and
warpages of holding pallets.

      Generally, hard disks, such as the 275 mm disks, are
automatically loaded by means of a robot onto a pallet which can hold
up to four disks.  After the disks are loaded onto the pallet, the
disks are subject to a sputtering process which subjects the disks
and pallet to high temperatures.  The high temperatures can cause
warpage to the pallet such that during the loading and unloading of
the disks, damage may occur to the disks.  The concept described
herein implements an algorithm which is used to compensate for the
warpage of the pallet.  From the computations, disks can be loaded
and unloaded by means of a robot onto a warped pallet without
dropping the disks.  The algorithm provides three primary
computations as follows:
  1.  Computation to find the center of the pallet to load the disk.
  2.  Compensation computation for the horizontal pallet warp by
computing the angle of the fourth axis.
  3.  Compensation computation for the horizontal pallet warp in the
X and Y directions.

      Fig. 1 shows a view from the the side facing the pallet.  The
objective is to find the center of the pallet for loading the disks,
using the locations as designated in Fig. 1.  Edge L-R is detected by
the laser, and its distance is computed from the coordinates in the Y
or vertical axis.  With point M known, center C must be computed from
the following data:
        L       = Point where the left edge is detected. Only the Y
or vertical coordinate is considered in this case.
        R       = Point where the right edge is detected. Only the Y
or vertical coordinate is considered in this case.
        A       = Angle between MR and CR
        MR      = LR/2
        CR      = 137.5 mm (Radius)...