Robust control of tape transport systems with no tension sensor

Robust Control of Nonlinear Tape Transport Systems With and Without Tension Sensors

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2397151 ◽

2006 ◽

Vol 129 (1) ◽

pp. 41-55 ◽

Cited By ~ 13

Author(s):

Matthew D. Baumgart ◽

Lucy Y. Pao

Keyword(s):

Robust Control ◽

Feedback Linearization ◽

State Feedback ◽

Transport Systems ◽

Tape Transport ◽

Control Laws ◽

Damping Characteristics ◽

Lyapunov Redesign ◽

Time Invariant ◽

Web Media

Web-winding systems, such as tape drives, are often modeled as linear and time-invariant, but at least two nonlinearities are common in these systems. First, the reel radii and moments of inertia change as web media spools from one reel to another. Second, friction can draw a thin layer of air between the layers of web media wrapped on the take-up reel, making the system’s spring and damping characteristics nonlinear by allowing a greater length of media to vibrate freely. In addition to these nonlinearities, there is often uncertainty in the motor parameters. In the first part of this paper, feedback linearization ideas motivate state feedback and changes of variables that transform the system into decoupled and intuitively meaningful tension and velocity loops. For the case where tension measurements are available, Lyapunov redesign techniques are then used to develop control laws that are robust with respect to these nonlinearities and uncertainties. The second part of this paper then develops an observer-based controller for the case where no tension measurements are available. Performance is established analytically for both the measurement-based and observer-based schemes. Simulations illustrate this performance.

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Characterization and Simulation of MIMO Transport Systems in Tape

ASME 2013 Conference on Information Storage and Processing Systems ◽

10.1115/isps2013-2925 ◽

2013 ◽

Author(s):

Giovanni Cherubini ◽

Angeliki Pantazi ◽

Jens Jelitto

Keyword(s):

Block Diagram ◽

Lateral Position ◽

Transport Systems ◽

Tape Transport ◽

Channel One ◽

Performance Improvements ◽

Improved Performance ◽

The Individual ◽

Hall Sensors ◽

Longitudinal Position

The potential for significant capacity and performance improvements in tape storage systems appears to be substantial [1],[2]. Advances in several areas, however, are necessary to foster increases in linear and track densities and consequently achieve higher cartridge capacities and improved performance [3],[4]. Reliable and precise tape transport and track-following servomechanisms are of fundamental importance to guarantee best read-channel performance on all parallel data channels during tape operation. In particular, tight control of tension and potentially of tape-dimensional stability (TDS) variations will be necessary for moving to thinner tape material, which in turn will enable an increase in volumetric density. Figure 1 shows the block diagram of conventional tape transport and track-following servomechanisms in a tape drive [5]. A digital dual servo channel provides estimates of the tape velocity, tape longitudinal position, and head lateral position, which are derived from signals read from dedicated servo bands [6]. Hall sensors provide tape velocity information from the individual reels, which typically is used in the absence of a valid velocity estimate from the servo channel. One of the main impairments affecting the performance of tape drives is the variation of tape tension [7],[8], which may be induced by, e.g., reel eccentricities.

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Robust control for railway transport networks based on stochastic P-timed Petri net models

Proceedings of the Institution of Mechanical Engineers Part I Journal of Systems and Control Engineering ◽

10.1177/0959651818823583 ◽

2019 ◽

Vol 233 (7) ◽

pp. 830-846

Author(s):

Mouhaned Gaied ◽

Anis M’halla ◽

Dimitri Lefebvre ◽

Kamel Ben Othmen

Keyword(s):

Robust Control ◽

Petri Nets ◽

Discrete Event Systems ◽

Optimization Problems ◽

Discrete Event ◽

Transport Systems ◽

Time Constraints ◽

Railway Transport ◽

Transport Networks ◽

Event Systems

This article is devoted to the modeling, performance evaluation and robust control of the railway transport network in Sahel Tunisia. The regular increase in the number of passengers makes the management of transportation systems more and more complex. Railway transport requires specific needs. Indeed, many decision and optimization problems occur from the planning phase to the implementation phase. Railway transport networks can be considered as discrete event systems with time constraints. The time factor is a critical parameter, since it includes schedules to be respected in order to avoid overlaps, delays and collisions between trains. The uncertainties affect the service and the availability of transportation resources and, consequently, the transport scheduling plan. Petri nets have been recognized as powerful modeling and analysis tools for discrete event systems with time constraints. Consequently, they are suitable for railway transport systems. In this article, stochastic P-time Petri nets are used for the railway transport networks in Sahel Tunisia. A global model is first detailed. Then, this model is used to analyze the network traffic and evaluate the performance of the system. Robustness again disturbances is introduced and a control strategy is developed to reduce the consequences of the disturbances in order to maintain the expected schedule.

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On Coupled Dynamics of Frictional Guides in Tape Transport Systems

2014 Conference on Information Storage and Processing Systems ◽

10.1115/isps2014-6971 ◽

2014 ◽

Author(s):

Hankang Yang ◽

Sinan Müftü

Keyword(s):

Mathematical Model ◽

Transport Systems ◽

Tape Recording ◽

Tape Transport ◽

Resonant Frequencies ◽

Lateral Tape Motion ◽

Frictional Damping ◽

Data Tape ◽

Lateral Friction ◽

Frictional Effects

Stationary guides introduce friction on to a travelling tape in the longitudinal and lateral directions. The longitudinal friction increases the tape tension and the lateral friction dampens the lateral tape motion (LTM). A comprehensive mathematical model of the coupled longitudinal and lateral tape dynamics is developed. Frictional effects over a cylindrical guide are modeled as concentrated loads in both longitudinal and lateral directions. In the range of tape transport velocities that are of interest to data tape recording, it was shown that frictional damping causes reduction of resonant frequencies and resonance amplitudes. Positioning of the guiding elements could significantly influence the dynamic response of LTM.

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