FREQUENCY-DOMAIN CHARACTERIZATION OF TAKE-UP REEL AIR-ENTRAINMENT IN LOW-TENSION AND HIGH-SPEED TAPE TRANSPORT

Air entrainment in tape spooling is important because it affects the t ape stacking quality and the dynamics for which the transport controll er must be designed Accurate estimates of the air film thickness betwe en the layers of tape are difficult to obtain by direct measurement. I n this paper, a new frequency domain method is presented where the len gth of the entrained air film is estimated by determining the spring c onstant of the unsupported tape span. Using multi-input single-output (MISO) frequency based system identification, the resonant frequency o f the system associated with the longitudinal mode of the tape is deri ved. These data are compared to predictions from the well known nip he ight equation. The utility of these equations is discussed.