DYNAMIC ANALYSIS OF ROBOTIC ARM FOR SECOND MODE OF VIBRATION

Abstract

Inertial forces, due to -self- weight of robotic arm, cause bending in the robotic arm which results in setting up of vibration which results in loss of accuracy and repeatability of the movements of robotic arm. In the present work it is proposed to analyze deflection produced by the vibrations under second mode of vibration, subsequent analysis are carried out for robotic arm under first mode of vibration and comparison is done between first and second mode of vibration results. This work models a robotic arm as a moving flexible beam. A linear motion is imposed on a harmonically vibrating stationary beam (Robotic arm). Value of initial deflection of stationary robotic arm (that is deflection before the arm starts translating) is calculated analytically by considering free vibration of stationary robotic arm). Equation of motion is developed for translating robotic arm. Numerical method of solution of partial differential equation have been employed to obtain a solution for the resulting behavior of the vibrating beam. The results are presented in the form of numerical values for the deflections of the free end or tip of robotic arm at calculated time intervals for increasing lengths of the arm, by plotting graph between arm tip deflection of robotic arm and time interval.