• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.181-188
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• 2000

Input shaping is a method fur reducing residual vibration. Vibration is eliminated by convolving an input shaper, which is a sequence of impulses, with the desired system command. It has been applied to robot with a flexible manipulator. But it can be applied to the reduction of residual vibration far overhead crane. In this paper, input shaping shows good performance for anti-sway of overhead crane. In the z-domain, we designed an input shaper and calculated the sensitivity of it. If sensitivity is calculated in the z-domain, the shapes of sensitivity curves are expected easily. Accordingly, it is easy to design an input shaper in the z-domain. We compared the response of a system with shaper to it without that. Also, we compared El shaper to ZV shaper in view of robustness.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.10
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• pp.1683-1693
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• 1997

In this paper, a new nonlinear dynamic model is derived for a 2-dimensional overhead crane based on a new definition of 2-degree-of-freedom swing angle, and a new anti-swing control law is proposed for the crane. The dynamic model and control law take simultaneous travel and traverse motions of the crane into consideration. The model is first linearized for small motions of the crane load about the vertical stable equilibrium. Then the model becomes decoupled and symmetric with respect to the travel and traverse axes of the crane. From this result, a decoupled anti-swing control law is proposed based on the linearized model via the loop shaping and root locus methods. This decoupled method guarantees not only fast damping of load-swing but also zero steady state position error with optimal transient response for the 2-dimensional motion of the crane. Finally, the proposed control method is evaluated by controlling the simultaneous travel and traverse motions of a 2-dimensional prototype overhead crane. The effectiveness of the proposed control method is then proven by the experimental results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.242-249
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• 2001

In this study, a methodology of synchronous control has been developed that can is applied to position synchronization of a two-axes driving system such as overhead crane. The synchronous error is caused by model uncertainties and torque load at each axis. To overcome these problems, the synchronous control system has been composed of two disturbance observers to calculate the torque disturbance and one synchronous controller to eliminate synchronous error. By considering model uncertainties of each axis, the synchronous controller has been designed using H(sub)$\infty$ control theory. The effectiveness of the proposed method has been verified through simulation.