Browse Prior Art Database

Detecting Surface Flaws on Storage Disks

IP.com Disclosure Number: IPCOM000062649D
Original Publication Date: 1986-Dec-01
Included in the Prior Art Database: 2005-Mar-09
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Ross, AI: AUTHOR [+2]

Abstract

During the production of disk files, there are a number of occasions when the disks are visually checked for the presence of surface abrasions. This has been done manually in the past, and the effectiveness depends on the operator's vision, concentration and the ambient lighting. The present article proposes performing such visual checks automatically by means of an image-capturing inspection system in which a television camera image of a sector of the disk surface is compared with a reference. The system captures images of successive sectors as the disk is spun, and these are compared with a stored image of the initial sector, which is used as the 'Master' sector for that disk. The proposed automated disk-surface flaw-detection system is shown in the drawing.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 2

Detecting Surface Flaws on Storage Disks

During the production of disk files, there are a number of occasions when the disks are visually checked for the presence of surface abrasions. This has been done manually in the past, and the effectiveness depends on the operator's vision, concentration and the ambient lighting. The present article proposes performing such visual checks automatically by means of an image-capturing inspection system in which a television camera image of a sector of the disk surface is compared with a reference. The system captures images of successive sectors as the disk is spun, and these are compared with a stored image of the initial sector, which is used as the 'Master' sector for that disk. The proposed automated disk-surface flaw-detection system is shown in the drawing. The system comprises a hard wired commercial vision system 1, two TV cameras and a variable frequency strobed lighting source 2 with associated mirrors 3. The system also includes a pneumatic chuck 4 to hold a disk 5 and an associated constant speed motor drive 6. The chuck 4 would be loaded with single disks by an industrial robot (not shown), whose controller is used to monitor and control the system. When a disk is loaded onto the chuck 4, a collet 7 is expanded to hold the disk on its internal diameter and the chuck is then rotated. The disk rotation speed, the strobe firing frequency and the storing and comparison of camera frames are all linked such that for a sector of angle A, and a disk rotational speed of...