VIBRATION REDUCTION OF THE NONLINEARLY TRAVELING STRING BY A MODIFIEDVARIABLE-STRUCTURE CONTROL WITH PROPORTIONAL AND INTEGRAL COMPENSATIONS

In recent years, the variable structure control (VSC) method is widely exploited for suppressing vibration. The reduction of vibration in an axially moving string can improve productive quality and enhance comp etitive ability. Our object of this paper is not only to supress vibra tion of the string, but also to achieve the command in a shorter time. The controllers, like VSC, fuzzy, neuro-network and so on, have not a chieved all the requirements of transient and steady-state situations; nevertheless, combining the advantages of different controllers is in evitable today. In our research, it is both to propose more cost-savin g controllers and to achieve not only suppressions of vibration string but decreasing time for transient and steady-state situations. (C) 19 98 Elsevier Science Ltd.