A state space model for interconnected rigid bodies

A state space model of interconnected rigid bodies is developed that is conceptually simple, employs a relatively small number of parameters for the representation of each link, and allows connection of an arbitrary number of elements in open or closed chains. The connection to other elements may be at arbitrary locations and with arbitrary joint constraints. Further, it allows for easy insertion of muscle-like actuators. The model involves three nonlinear feedback loops for each rigid body: local angular velocity, state feedback for connection and joint constraints, and finally, output muscle feedback. This model is most suitable for computer simulation of large natural and man-made systems. The basic characteristics of this model and two examples are presented.