Author: Wong, Kam-hon Richard
Title: Automatic control for active vibration isolation system
Degree: M.Sc.
Year: 1995
Subject: Vibration
Control theory
Damping (Mechanics)
Hong Kong Polytechnic University -- Dissertations
Department: Multi-disciplinary Studies
Pages: 154 leaves : ill. ; 30 cm
Language: English
Abstract: Vibration isolation is a reduction in the capacity of the system to respond to an excitation, attained by the use of isolator. In steady state forced vibration, isolation is expressed quantitatively as the complement of transmissibility. Previous studies of vibration control focus on design modifications to change effective damping and stiffness, which is called passive vibration control. Adaptation to complicated, time varying conditions calls for vibration control through application of external, actively updated driving forces, which is called active vibration control. The active vibration isolation system is studied theoretically and experimentally in this project. Firstly, the characteristics of passive vibration isolation system is analyzed, and the effects of the system parameters, i.e. mass, stiffness and transmissibility were discussed. Secondly, this study deals with active vibration isolation technique to improve the isolation performance. The effects of controllability and observability are analyzed, and a modification to the set-up is proposed to design an active controller for this vibration system. Some important conclusions are drawn, which are the theoretical basis for the design of active controlled vibration systems. The aim of this dissertation is to demostrate that the thoery of Active Vibration Isolation System can be applied to the real situation such that the vibration amplitude can be reduced by chosing suitable system parameters. The digital computer simulation and experiment are conducted to verify the effectiveness of the active vibration control, in which the micro-computer 80286 is used as the controller, and experimential results are obtained.
Rights: All rights reserved
Access: restricted access

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