Automatic Generation of Equations of Motion from Graphic Input of Vibration Model : A System for Two-Dimensional Vibrations of Multibody Systems

Abstract

In order to make vibration analysis an easily input, automated task for designers, it is desirable to develop an interactive vibration analysis system, using personal computers or engineering work stations which have a user-friendly interface for easy input of the vibration model, and which can perform automatic generation of equations of motion, and automatic numerical analysis of them. As the first step towards such a system, an automatic generation system of equations of motion was developed for two-dimensional vibrations of multibody systems. The system is written in Smalltalk-80, which is a typical object-oriented language having the following advantages : (1) user-friendly interface for graphic input of a vibration model, enabling users to make a variety of configurations of a vibration model on the display by choosing the vibration model elements listed in the menu with a pointing device (mouse) ; (2) applicability to extensive models of two-dimensional vibrations of multibody systems which contain various constraints and nonlinear elements.