Frequency Domain Characterization of Take-Up Reel Air-Entrainment in Low-Tension and High-Speed Tape Transport

Air entrainment in tape spooling is important in determining tape stacking quality and in modeling the transport system for control purposes. Accurate estimates are difficult to obtain by direct measurement. In this paper, the length of the entrained air film is estimated by determining the spring constant of the unsupported tape span. Using multi-input single-output (MISO) frequency based system identification, the resonant frequency of the system associated with the longitudinal mode of the tape is derived. This data is compared to predictions from the well known nip equation. The utility of these equations is discussed.