63964 ANALYSIS OF MULTIBODY SYSTEMS BASED ON THE MODIFIED HAMILTON'S PRINCIPLE : ELIMINATION OF THE LAGRANGE MULTIPLIERS BASED ON THE NULL SPACE METHOD(Modeling, Formalisms, and DAE Solution Method)

Abstract

The governing equations for multibody systems are often formulated in the form of differential algebraic equations (DAEs) involving the Lagrange multipliers. As a method to solve the DAEs by eliminating the Lagrange multipliers, there is a method called the null space method. In a previous report, one of the authors presented procedure to formulate the governing equations of multibody systems by using the variational principle called the modified Hamilton's principle. The governing equation obtained by the presented procedure involves the Lagrange multipliers. In this report, use of the null space method in the modified Hamilton's principle is discussed. Then, a new method to obtain the null space matrix is presented. Finally, numerical examples are shown.