Radius Corrected Friction Compensation
Original Publication Date: 1987-Mar-01
Included in the Prior Art Database: 2005-Feb-01
Existing tape drive servo controls for tension use a fixed number for friction drag that is not corrected for radius change. This results in an excessive tension fluctuation for small diameter reels and insufficient compensation for large diameter reels, as shown in Fig. 1. An improved algorithm can be used to link half the drag compensation to the radius of the reel. Thus: Friction dependent upon the reel radius: a. tape path drag b. peeling of tape from reel Friction independent of the reel radius: c. motor bearing and brushes d. hub aerodynamic drag e. cartridge button and leader block. Improved algorithm: IDRAG 1 = 1/4 SHELL 1 + 4 IDRAG 2 = 1/4 SHELL 2 + 4 (Image Omitted) IDRAG 1 + IDRAG 2 = 1/4 (SHELL 1 + SHELL 2) + 8 = 12 (HEXADECIMAL) See Fig. 2.