DYNAMIC ANALYSIS AND VIBRATION CONTROL OF A MULTI-BODY SYSTEM USING MSC ADAMS

Abstract

IN THIS PAPER, MODELLING AND SIMULATION OF A MULTI-BODY SYSTEM FOR ITS VIBRATION CONTROL USING SENSORS AND ACTUATORS IS PRESENTED. THE MODEL DEVELOPED ON MSC ADAMS CONSISTS OF SIX LEGS CONNECTING MOVING AND BASE PLATES USING SPHERICAL JOINTS WITH AXIAL ROTATION OF LEGS CONSTRAINED. IT CONTAINS LINEAR ACTUATOR COLLOCATED WITH FORCE SENSOR. MATHEMATICAL MODEL OF THE MECHANISM REPRESENTING THE KINEMATIC AND DYNAMIC ANALYSIS OF MODEL IS PRESENTED. THE LEG LENGTH VARIATION OBTAINED USING MATLAB IS OBTAINED IN ORDER TO VALIDATE THE MODEL DEVELOPED IN MSC ADAMS. NATURAL FREQUENCIES FOR SIX DIFFERENT MODE SHAPES ARE OBTAINED FROM VIBRATION EXCITA-TION ANALYSIS. A DECENTRALIZED FORCE FEEDBACK CONTROLLER WHICH USES PID CONTROL LAW WITH SINGLE GAIN IS USED FOR ACTIVELY ATTENUATING THE VIBRATION, WHICH IS COMING FROM BASE PLATFORM. THE TRANSFER FUNC-TION, DEFINED AS THE RATIO OF LAPLACE TRANSFORMATION OF THE ACCELERA-TION OF MOVING PLATE AND BASE PLATE, IS CONSIDERED AS A MEASURE OF ISOLATION. EFFECT OF PROPORTIONAL, DERIVATIVE AND INTEGRAL FEEDBACK IS STUDIED SEPARATELY AND TOGETHER AS WELL. A SIGNIFICANT ISOLATION IN THE RESONANCE TRANSMISSIBILITY AND NATURAL FREQUENCY OF THE MECH-ANISM IS DEMONSTRATED.