Numerical computation of differential-algebraic equations for nonlinear dynamics of multibody android systems in automobile crash simulation

The principle of virtual work is used to derive the Euler-Lagrange equation s of motion in order to describe the dynamics of multibody android systems. The constrained variational equations are in fact differential-algebraic e quations of high index and are cast as ordinary differential equations thro ugh differentiation of the constraint equations, The integration routine LS ODAR and the fourth-order Runge-Kutta method are used to compute the genera lized coordinates, their time derivatives and the body forces of two androi d models, The graphs of the constraint forces reveal the whiplash effect on the neck and that the stiffness of both multibody systems is due to large magnitude impulsive forces experienced by many bodies simultaneously.