The dynamics of an articulated forestry machine and its applications

This paper focuses on the generation of dynamic models for an articulated forestry machine. Such models can be used for training simulators, for sizing components, and for control. The most complex model includes base compliance, and pendulum-like motions of the processing head suspended from an end-point. A Newton-Euler iterative method, implemented symbolically, is used to include base degrees-of-freedom due to the machine's compliant tires. Techniques and experiments designed to extract system parameters are described. Based on the obtained models, a novel valve-sizing methodology is outlined. Finally, simulation results of the machine's response are provided.