2. Geometry and kinematics of multibody systems

2.1 Choice of generalized coordinates

We have already mentioned the two main categories of parameters used in mechanism simulation software.

Absolute parameterization (ADAMS, DADS...) appears to be the most suitable for algorithmic purposes, since it consists in describing the orientation of each solid and choosing the Cartesian coordinates of a point linked to it. For dynamic applications, there is no simpler, more systematic way to operate. Acceleration quantities then have an immutable form. But then all links give rise to a number of link equations equal to 6 minus its degree of freedom.

We've already said that the identical equations of dynamics, whose formation we'll be examining, are not worth knowing. Moreover, the very large...